market structures and competition assignment

• school Campus Bookshelves
• menu_book Bookshelves
• perm_media Learning Objects
• login Login
• how_to_reg Request Instructor Account
• hub Instructor Commons

Margin Size

• Download Page (PDF)
• Download Full Book (PDF)
• Periodic Table
• Physics Constants
• Scientific Calculator
• Reference & Cite
• Tools expand_more
• Readability

selected template will load here

This action is not available.

2.9: Competition and Market Structures

• Last updated
• Save as PDF
• Page ID 6768

\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)

\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)

\( \newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\)

( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\)

\( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)

\( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\)

\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)

\( \newcommand{\Span}{\mathrm{span}}\)

\( \newcommand{\id}{\mathrm{id}}\)

\( \newcommand{\kernel}{\mathrm{null}\,}\)

\( \newcommand{\range}{\mathrm{range}\,}\)

\( \newcommand{\RealPart}{\mathrm{Re}}\)

\( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)

\( \newcommand{\Argument}{\mathrm{Arg}}\)

\( \newcommand{\norm}[1]{\| #1 \|}\)

\( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\AA}{\unicode[.8,0]{x212B}}\)

\( \newcommand{\vectorA}[1]{\vec{#1}}      % arrow\)

\( \newcommand{\vectorAt}[1]{\vec{\text{#1}}}      % arrow\)

\( \newcommand{\vectorB}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)

\( \newcommand{\vectorC}[1]{\textbf{#1}} \)

\( \newcommand{\vectorD}[1]{\overrightarrow{#1}} \)

\( \newcommand{\vectorDt}[1]{\overrightarrow{\text{#1}}} \)

\( \newcommand{\vectE}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{\mathbf {#1}}}} \)

Competition and Market Structures

Market structures describe the nature or degree of competition among companies, in the same industries, in a free enterprise economy. Economists have developed a theoretical model of an ideal situation where “perfect competition” occurs. Of course, this is only a model to compare to other types of market structures that are not “perfect”.

For there to be “perfect competition” certain conditions must prevail in the market such as:

• a large number of buyers and sellers,
• they must deal in identical products,
• buyers and sellers act independently and compete with each other,
• both buyers and sellers must be well informed of the conditions in the markets, and
• both buyers and sellers can enter into and leave the market whenever they choose.

So as you may have determined from the five conditions that must exist to have “perfect competition,” there really is no such thing. If any of the five conditions are not met, then the market structure is called “imperfect”.

There are three “imperfect markets”: monopolistic competition, oligopoly, and monopoly.

Universal Generalizations

• Perfect competition is a theory used to evaluate other types of markets.
• There are four basic types of market structures: perfect, monopolistic, oligopoly, and monopoly.
• The type of market structure is determined by the amount of competition among firms operating in the same industry.
• Competition in the marketplace affects price, demand, and supply of goods and services.

Guiding Questions

• How do changes in prices affect demand for goods and/or services for each type of market structure?
• Why does the government allow for monopolies to exist?
• To what extent should the government be involved in the free enterprise market?

Video: Market Structures

Market Structures

Firms behave in much the same way as consumers behave. What does that mean? Let’s define what is meant by the firm. A firm (or business) combines inputs of labor, capital, land, and raw or finished component materials to produce outputs. If the firm is successful, the outputs are more valuable than the inputs. This activity of production goes beyond manufacturing (i.e., making things). It includes any process or service that creates value, including transportation, distribution, wholesale and retail sales. Production involves a number of important decisions that define the behavior of firms. These decisions include, but are not limited to:

• What product or products should the firm produce?
• How should the products be produced (i.e., what production process should be used)?
• How much output should the firm produce?
• What price should the firm charge for its products?
• How much labor should the firm employ?

What It Means: Three Economic Questions: What, How, For Whom?

Three Economic Questions

In order to meet the needs of its people, every society must answer three basic economic questions:

• What should we produce?
• How should we produce it?
• For whom should we produce it?

A society (or country) might decide to produce candy or cars, computers or combat boots. The goods might be produced by unskilled workers in privately owned factories or by technical experts in government-funded laboratories. Once they are made, the goods might be given out for free to the poor or sold at high prices that only the rich can afford. The possibilities are endless.

Although every society answers the three basic economic questions differently, in doing so, each confronts the same fundamental problems: resource allocation and scarcity.

Resources are all of the ingredients needed for production, including physical materials (such as land, coal, or timber), labor (workers), technology (not just computers but, in a broader sense, all the technical ability and knowledge that is necessary to produce a given commodity), and capital (the machinery and tools of production). Scarcity refers to the essential fact that people’s wants or desires are always going to be greater than the resources available to fulfill those wants.

Simply put, scarcity means that resources are limited. No country can produce everything, no matter how rich its mines, how massive its forests, or how advanced its technology. Because of the constraints of scarcity, then, decisions must be made about resource allocation (that is, how best to allocate, or distribute, resources for the maximum benefit of the society).

Source: "Three Economic Questions: What, How, For Whom?." Everyday Finance: Economics, Personal Money Management, and Entrepreneurship. Retrieved June 13, 2018 from Encyclopedia.com: http://www.encyclopedia.com/finance/...-what-how-whom

The answers to these questions depend on the production and cost conditions facing each firm. The answers also depend on the structure of the market for the product(s) in question. Market structure is a multidimensional concept that involves how competitive the industry is. It is defined by questions such as these:

• How much market power does each firm in the industry possess?
• How similar is each firm’s product to the products of other firms in the industry?
• How difficult is it for new firms to enter the industry?
• Do firms compete on the basis of price, advertising, or other product differences?

Figure 2 illustrates the range of different market structures

Firms face different competitive situations. At one extreme—perfect competition—many firms are all trying to sell identical products. At the other extreme—monopoly—only one firm is selling the product, and this firm faces no competition. Monopolistic competition and oligopoly fall between the extremes of perfect competition and monopoly. Monopolistic competition is a situation with many firms selling similar, but not identical, products. Oligopoly is a situation with few firms that sell identical or similar products.

Case Study: Amazon

In less than two decades, Amazon.com has transformed the way books are sold, bought, and even read. Prior to Amazon, books were primarily sold through independent bookstores with limited inventories in small retail locations. There were exceptions, of course; Borders and Barnes & Noble offered larger stores in urban areas. In the last decade, however, independent bookstores have become few and far between, Borders has gone out of business, and Barnes & Noble is struggling. Online delivery and purchase of books has indeed overtaken the more traditional business models. How has Amazon changed the book selling industry? How has it managed to crush its competition?

A major reason for the giant retailer’s success is its production model and cost structure, which has enabled Amazon to undercut the prices of its competitors even when factoring in the cost of shipping. Read on to see how firms great (like Amazon) and small (like your corner deli) determine what to sell, at what output and price.

Traditionally, bookstores have operated in retail locations with inventories held either on the shelves or in the back of the store. These retail locations were very pricey in terms of rent. Amazon has no retail locations; it sells online and delivers by mail. Amazon offers almost any book in print, convenient purchasing, and prompt delivery by mail. Amazon holds its inventories in huge warehouses in low-rent locations around the world. The warehouses are highly computerized using robots and relatively low-skilled workers, making for low average costs per sale. Amazon demonstrates the significant advantages economies of scale can offer to a firm that exploits those economies.

Perfect Competition and Why It Matters

Firms are said to be in perfect competition when the following conditions occur: (1) many firms produce identical products; (2) many buyers are available to buy the product, and many sellers are available to sell the product; (3) sellers and buyers have all relevant information to make rational decisions about the product being bought and sold; and (4) firms can enter and leave the market without any restrictions—in other words, there is free entry and exit into and out of the market.

A perfectly competitive firm is known as a price taker because the pressure of competing firms forces them to accept the prevailing equilibrium price in the market. If a firm in a perfectly competitive market raises the price of its product by so much as a penny, it will lose all of its sales to competitors. When a wheat grower, as discussed in the Bring it Home feature, wants to know what the going price of wheat is, he or she has to go to the computer or listen to the radio to check. The market price is determined solely by supply and demand in the entire market and not the individual farmer. Also, a perfectly competitive firm must be a very small player in the overall market, so that it can increase or decrease output without noticeably affecting the overall quantity supplied and price in the market.

A perfectly competitive market is a hypothetical extreme; however, producers in a number of industries do face many competitor firms selling highly similar goods, in which case they must often act as price takers. Agricultural markets are often used as an example. The same crops grown by different farmers are largely interchangeable. According to the United States Department of Agriculture monthly reports, in 2012, U.S. corn farmers received an average price of $6.07 per bushel and wheat farmers received an average price of $7.60 per bushel. A corn farmer who attempted to sell at $7.00 per bushel, or a wheat grower who attempted to sell for $8.00 per bushel would not have found any buyers. A perfectly competitive firm will not sell below the equilibrium price either. Why should they when they can sell all they want at the higher price? Other examples of agricultural markets that operate in close to perfectly competitive markets are small roadside produce markets and small organic farmers.

This chapter examines how profit-seeking firms decide how much to produce in perfectly competitive markets. In the short run, the perfectly competitive firm will seek the quantity of output where profits are highest or, if profits are not possible, where losses are lowest. In this example, the “short run” refers to a situation in which firms are producing with one fixed input and incur fixed costs of production. (In the real world, firms can have many fixed inputs.)

In the long run, perfectly competitive firms will react to profits by increasing production. They will respond to losses by reducing production or exiting the market. Ultimately, a long-run equilibrium will be attained when no new firms want to enter the market and existing firms do not want to leave the market, as economic profits have been driven down to zero.

How Perfectly Competitive Firms Make Output Decisions

A perfectly competitive firm has only one major decision to make—namely, what quantity to produce. To understand why this is so, consider a different way of writing out the basic definition of profit:

Profit=Total revenue−Total cost

=(Price)(Quantity produced)−(Average cost)(Quantity produced)

Since a perfectly competitive firm must accept the price for its output as determined by the product’s market demand and supply, it cannot choose the price it charges. This is already determined in the profit equation, and so the perfectly competitive firm can sell any number of units at exactly the same price. It implies that the firm faces a perfectly elastic demand curve for its product: buyers are willing to buy any number of units of output from the firm at the market price. When the perfectly competitive firm chooses what quantity to produce, then this quantity—along with the prices prevailing in the market for output and inputs—will determine the firm’s total revenue, total costs, and ultimately, level of profits.

Determining the Highest Profit by Comparing Total Revenue and Total Cost

A perfectly competitive firm can sell as large a quantity as it wishes, as long as it accepts the prevailing market price. Total revenue is going to increase as the firm sells more, depending on the price of the product and the number of units sold. If you increase the number of units sold at a given price, then total revenue will increase. If the price of the product increases for every unit sold, then total revenue also increases. As an example of how a perfectly competitive firm decides what quantity to produce, consider the case of a small farmer who produces raspberries and sells them frozen for $4 per pack. Sales of one pack of raspberries will bring in $4, two packs will be $8, three packs will be $12, and so on. If, for example, the price of frozen raspberries doubles to $8 per pack, then sales of one pack of raspberries will be $8, two packs will be $16, three packs will be $24, and so on.

Total revenue and total costs for the raspberry farm, broken down into fixed and variable costs, are shown in Table 1 and also appear in Figure 3. The horizontal axis shows the quantity of frozen raspberries produced in packs; the vertical axis shows both total revenue and total costs, measured in dollars. The total cost curve intersects with the vertical axis at a value that shows the level of fixed costs, and then slopes upward.

Total Cost and Total Revenue at the Raspberry Farm

Total revenue for a perfectly competitive firm is a straight line sloping up. The slope is equal to the price of the good. Total cost also slopes up, but with some curvature. At higher levels of output, total cost begins to slope upward more steeply because of diminishing marginal returns. The maximum profit will occur at the quantity where the gap of total revenue over total cost is largest.

Based on its total revenue and total cost curves, a perfectly competitive firm like the raspberry farm can calculate the quantity of output that will provide the highest level of profit. At any given quantity, total revenue minus total cost will equal profit. One way to determine the most profitable quantity to produce is to see at what quantity total revenue exceeds total cost by the largest amount. In Figure 3, the vertical gap between total revenue and total cost represents either profit (if total revenues are greater than total costs at a certain quantity) or losses (if total costs are greater than total revenues at a certain quantity). In this example, total costs will exceed total revenues at output levels from 0 to 40, and so over this range of output, the firm will be making losses. At output levels from 50 to 80, total revenues exceed total costs, so the firm is earning profits. But then at an output of 90 or 100, total costs again exceed total revenues and the firm is making losses. The highest total profits in the figure, occur at an output of 70–80, when profits will be $56.

A higher price would mean that total revenue would be higher for every quantity sold. A lower price would mean that total revenue would be lower for every quantity sold. What happens if the price drops low enough so that the total revenue line is completely below the total cost curve; that is, at every level of output, total costs are higher than total revenues? In this instance, the best the firm can do is to suffer losses. But a profit-maximizing firm will prefer the quantity of output where total revenues come closest to total costs and thus where the losses are smallest.

Entry and Exit Decisions in the Long Run

The line between the short run and the long run cannot be defined precisely with a stopwatch or even with a calendar. It varies according to the specific business. The distinction between the short run and the long run is, therefore, more technical: in the short run, firms cannot change the usage of fixed inputs, while in the long run, the firm can adjust all factors of production.

In a competitive market, profits are a red cape that incite businesses to charge. If a business is making a profit in the short run, it has an incentive to expand existing factories or to build new ones. New firms may start production, as well. When new firms enter the industry in response to increased industry profits it is called entry.

Losses are the black thundercloud that causes businesses to flee. If a business is making losses in the short run, it will either keep limping along or just shut down, depending on whether its revenues are covering its variable costs. But in the long run, firms that are facing losses will shut down at least some of their output, and some firms will cease production altogether. The long run process of reducing production in response to a sustained pattern of losses is called exit. The following Clear It Up feature discusses where some of these losses might come from, and the reasons why some firms go out of business.

Why do Firms Cease to Exist?

Can we say anything about what causes a firm to exit an industry? Profits are the measurement that determines whether a business stays operating or not. Individuals start businesses with the purpose of making profits. They invest their money, time, effort, and many other resources to produce and sell something that they hope will give them something in return. Unfortunately, not all businesses are successful, and many new startups soon realize that their “business adventure” must eventually end.

In the model of perfectly competitive firms, those that consistently cannot make money will “exit,” which is a nice, bloodless word for a more painful process. When a business fails, after all, workers lose their jobs, investors lose their money, and owners and managers can lose their dreams. Many businesses fail. The U.S. Small Business Administration indicates that in 2009–2010, for example, 533,945 firms “entered” in the United States, but 593,347 firms “exited.” About 96.3% and 96.6% of these business entries and exits, respectively, involved small firms with fewer than 20 employees.

Sometimes a business fails because of poor management or workers who are not very productive, or because of tough domestic or foreign competition. Businesses also fail from a variety of causes that might best be summarized as bad luck. For example, conditions of demand and supply in the market shift in an unexpected way, so that the prices that can be charged for outputs fall or the prices that need to be paid for inputs rise. With millions of businesses in the U.S. economy, even a small fraction of them failing will affect many people—and business failures can be very hard on the workers and managers directly involved. But from the standpoint of the overall economic system, business exits are sometimes a necessary evil if a market-oriented system is going to offer a flexible mechanism for satisfying customers, keeping costs low, and inventing new products.

Video: Comparing Market Structures

How Entry and Exit Lead to Zero Profits in the Long Run

No perfectly competitive firm acting alone can affect the market price. However, the combination of many firms entering or exiting the market will affect overall supply in the market. In turn, a shift in supply for the market as a whole will affect the market price. Entry and exit to and from the market are the driving forces behind a process that, in the long run, pushes the price down to minimum average total costs so that all firms are earning a zero profit.

To understand how short-run profits for a perfectly competitive firm will evaporate in the long run, imagine the following situation. The market is in long-run equilibrium, where all firms earn zero economic profits producing the output level where P = MR = MC and P = AC. No firm has the incentive to enter or leave the market. Let’s say that the product’s demand increases, and with that, the market price goes up. The existing firms in the industry are now facing a higher price than before, so they will increase production to the new output level where P = MR = MC.

This will temporarily make the market price rise above the average cost curve, and therefore, the existing firms in the market will now be earning economic profits. However, these economic profits attract other firms to enter the market. Entry of many new firms causes the market supply curve to shift to the right. As the supply curve shifts to the right, the market price starts decreasing, and with that, economic profits fall for new and existing firms. As long as there are still profits in the market, entry will continue to shift supply to the right. This will stop whenever the market price is driven down to the zero-profit level, where no firm is earning economic profits.

Short run losses will fade away by reversing this process. Say that the market is in long run equilibrium. This time, demand decreases, and with that, the market price starts falling. The existing firms in the industry are now facing a lower price than before, and as it will be below the average cost curve, they will now be making economic losses. Some firms will continue producing where the new P = MR = MC, as long as they are able to cover their average variable costs. Some firms will have to shut down immediately as they will not be able to cover their average variable costs, and then will only incur their fixed costs, minimizing their losses. Exit of many firms causes the market supply curve to shift to the left. As the supply curve shifts to the left, the market price starts rising, and economic losses start to be lower. This process ends whenever the market price rises to the zero-profit level, where the existing firms are no longer losing money and are at zero profits again. Thus, while a perfectly competitive firm can earn profits in the short run, in the long run the process of entry will push down prices until they reach the zero-profit level. Conversely, while a perfectly competitive firm may earn losses in the short run, firms will not continually lose money. In the long run, firms making losses are able to escape from their fixed costs, and their exit from the market will push the price back up to the zero-profit level. In the long run, this process of entry and exit will drive the price in perfectly competitive markets to the zero-profit point at the bottom of the AC curve, where marginal cost crosses average cost.

The Long Run Adjustment and Industry Types

Whenever there are expansions in an industry, costs of production for the existing and new firms could either stay the same, increase, or even decrease. Therefore, we can categorize an industry as being (1) a constant cost industry (as demand increases, the cost of production for firms stays the same), (2) an increasing cost industry (as demand increases, the cost of production for firms increases), or (3) a decreasing cost industry (as demand increases the costs of production for the firms decreases).

For a constant cost industry, whenever there is an increase in market demand and price, then the supply curve shifts to the right with new firms’ entry and stops at the point where the new long-run equilibrium intersects at the same market price as before. But why will costs remain the same? In this type of industry, the supply curve is very elastic. Firms can easily supply any quantity that consumers demand. In addition, there is a perfectly elastic supply of inputs—firms can easily increase their demand for employees, for example, with no increase to wages. Tying in to our Bring it Home discussion, an increased demand for ethanol in recent years has caused the demand for corn to increase. Consequently, many farmers switched from growing wheat to growing corn. Agricultural markets are generally good examples of constant cost industries.

For an increasing cost industry, as the market expands, the old and new firms experience increases in their costs of production, which makes the new zero-profit level intersect at a higher price than before. Here companies may have to deal with limited inputs, such as skilled labor. As the demand for these workers rise, wages rise and this increases the cost of production for all firms. The industry supply curve in this type of industry is more inelastic.

For a decreasing cost industry, as the market expands, the old and new firms experience lower costs of production, which makes the new zero-profit level intersect at a lower price than before. In this case, the industry and all the firms in it are experiencing falling average total costs. This can be due to an improvement in technology in the entire industry or an increase in the education of employees. High tech industries may be a good example of a decreasing cost market.

Figure 4 (a) presents the case of an adjustment process in a constant cost industry. Whenever there are output expansions in this type of industry, the long-run outcome implies more output produced at exactly the same original price. Note that supply was able to increase to meet the increased demand. When we join the before and after long-run equilibriums, the resulting line is the long run supply (LRS) curve in perfectly competitive markets. In this case, it is a flat curve. Figure 4(b) and Figure 4 (c) present the cases for an increasing cost and decreasing cost industry, respectively. For an increasing cost industry, the LRS is upward sloping, while for a decreasing cost industry, the LRS is downward sloping.

Adjustment Process in a Constant-Cost Industry

In (a), demand increased and supply met it. Notice that the supply increase is equal to the demand increase. The result is that the equilibrium price stays the same as quantity sold increases. In (b), notice that sellers were not able to increase supply as much as demand. Some inputs were scarce, or wages were rising. The equilibrium price rises. In (c), sellers easily increased supply in response to the demand increase. Here, new technology or economies of scale caused the large increase in supply, resulting in declining equilibrium price.

Efficiency in Perfectly Competitive Markets

When profit-maximizing firms in perfectly competitive markets combine with utility-maximizing consumers, something remarkable happens: the resulting quantities of outputs of goods and services demonstrate both productive and allocative efficiency.

Productive efficiency means producing without waste, so that the choice is on the production possibility frontier. In the long run in a perfectly competitive market, because of the process of entry and exit, the price in the market is equal to the minimum of the long-run average cost curve. In other words, goods are being produced and sold at the lowest possible average cost.

Allocative efficiency means that among the points on the production possibility frontier, the point that is chosen is socially preferred—at least in a particular and specific sense. In a perfectly competitive market, price will be equal to the marginal cost of production. Think about the price that is paid for a good as a measure of the social benefit received for that good; after all, willingness to pay conveys what the good is worth to a buyer. Then think about the marginal cost of producing the good as representing not just the cost for the firm, but more broadly as the social cost of producing that good. When perfectly competitive firms follow the rule that profits are maximized by producing at the quantity where price is equal to marginal cost, they are thus ensuring that the social benefits received from producing a good are in line with the social costs of production.

To explore what is meant by allocative efficiency, it is useful to walk through an example. Begin by assuming that the market for wholesale flowers is perfectly competitive, and so P = MC. Now, consider what it would mean if firms in that market produced a lesser quantity of flowers. At a lesser quantity, marginal costs will not yet have increased as much, so that price will exceed marginal cost; that is, P > MC. In that situation, the benefit to society as a whole of producing additional goods, as measured by the willingness of consumers to pay for marginal units of a good, would be higher than the cost of the inputs of labor and physical capital needed to produce the marginal good. In other words, the gains to society as a whole from producing additional marginal units will be greater than the costs.

Conversely, consider what it would mean if, compared to the level of output at the allocatively efficient choice when P = MC, firms produced a greater quantity of flowers. At a greater quantity, marginal costs of production will have increased so that P < MC. In that case, the marginal costs of producing additional flowers is greater than the benefit to society as measured by what people are willing to pay. For society as a whole, since the costs are outstripping the benefits, it will make sense to produce a lower quantity of such goods.

When perfectly competitive firms maximize their profits by producing the quantity where P = MC, they also assure that the benefits to consumers of what they are buying, as measured by the price they are willing to pay, is equal to the costs to society of producing the marginal units, as measured by the marginal costs the firm must pay—and thus that allocative efficiency holds.

The statements that a perfectly competitive market in the long run will feature both productive and allocative efficiency do need to be taken with a few grains of salt. Remember, economists are using the concept of “efficiency” in a particular and specific sense, not as a synonym for “desirable in every way.” For one thing, consumers’ ability to pay reflects the income distribution in a particular society. Thus, a homeless person may have no ability to pay for housing because they have insufficient income.

Perfect competition, in the long run, is a hypothetical benchmark. For market structures such as monopoly, monopolistic competition, and oligopoly, which are more frequently observed in the real world than perfect competition, firms will not always produce at the minimum of average cost, nor will they always set price equal to marginal cost. Thus, these other competitive situations will not produce productive and allocative efficiency.

Moreover, real-world markets include many issues that are assumed away in the model of perfect competition, including pollution, inventions of new technology, poverty which may make some people unable to pay for basic necessities of life, government programs like national defense or education, discrimination in labor markets, and buyers and sellers who must deal with imperfect and unclear information. These issues are explored in other chapters. However, the theoretical efficiency of perfect competition does provide a useful benchmark for comparing the issues that arise from these real-world problems.

There is a widespread belief that top executives at firms are the strongest supporters of market competition, but this belief is far from the truth. Think about it this way: If you very much wanted to win an Olympic gold medal, would you rather be far better than everyone else, or locked in competition with many athletes just as good as you are? Similarly, if you would like to attain a very high level of profits, would you rather manage a business with little or no competition, or struggle against many tough competitors who are trying to sell to your customers?

If perfect competition is a market where firms have no market power and they simply respond to the market price, monopoly is a market with no competition at all, and firms have complete market power. In the case of monopoly, one firm produces all of the output in a market. Since a monopoly faces no significant competition, it can charge any price it wishes. While a monopoly, by definition, refers to a single firm, in practice the term is often used to describe a market in which one firm merely has a very high market share. This tends to be the definition that the U.S. Department of Justice uses.

Even though there are very few true monopolies in existence, we do deal with some of those few every day, often without realizing it: The U.S. Postal Service, your electric and garbage collection companies are a few examples. Some new drugs are produced by only one pharmaceutical firm—and no close substitutes for that drug may exist.

From the mid-1990s until 2004, the U.S. Department of Justice prosecuted the Microsoft Corporation for including Internet Explorer as the default web browser with its operating system. The Justice Department’s argument was that, since Microsoft possessed an extremely high market share in the industry for operating systems, the inclusion of a free web browser constituted unfair competition to other browsers, such as Netscape Navigator. Since nearly everyone was using Windows, including Internet Explorer eliminated the incentive for consumers to explore other browsers and made it impossible for competitors to gain a foothold in the market. In 2013, the Windows system ran on more than 90% of the most commonly sold personal computers.

Monopolies are protected from competition, including laws that prohibit competition, technological advantages, and certain configurations of demand and supply. It then discusses how a monopoly will choose its profit-maximizing quantity to produce and what price to charge. While a monopoly must be concerned about whether consumers will purchase its products or spend their money on something altogether different, the monopolist need not worry about the actions of other competing firms producing its products. As a result, a monopoly is not a price taker like a perfectly competitive firm, but instead exercises some power to choose its market price.

Video: Monopolies and Anti-Competitive Markets

How Monopolies Form: Barriers to Entry

Because of the lack of competition, monopolies tend to earn significant economic profits. These profits should attract vigorous competition, and yet, because of one particular characteristic of monopoly, they do not. Barriers to entry are the legal, technological, or market forces that discourage or prevent potential competitors from entering a market. Barriers to entry can range from the simple and easily surmountable, such as the cost of renting retail space, to the extremely restrictive. For example, there are a finite number of radio frequencies available for broadcasting. Once the rights to all of them have been purchased, no new competitors can enter the market.

In some cases, barriers to entry may lead to monopoly. In other cases, they may limit competition to a few firms. Barriers may block entry even if the firm or firms currently in the market are earning profits. Thus, in markets with significant barriers to entry, it is not true that abnormally high profits will attract new firms, and that this entry of new firms will eventually cause the price to decline so that surviving firms earn only a normal level of profit in the long run.

There are two types of monopolies based on the types of barriers to entry they exploit. One is natural monopoly where the barriers to entry are something other than legal prohibition. The other is legal monopoly where laws prohibit (or severely limit) competition.

Natural Monopoly

Economies of scale can combine with the size of the market to limit competition. This situation, when economies of scale are large relative to the quantity demanded in the market, is called a natural monopoly. Natural monopolies often arise in industries where the marginal cost of adding an additional customer is very low, once the fixed costs of the overall system are in place. Once the main water pipes are laid through a neighborhood, the marginal cost of providing water service to another home is fairly low. Once electricity lines are installed through a neighborhood, the marginal cost of providing additional electrical service to one more home is very low. It would be costly and duplicative for a second water company to enter the market and invest in a whole second set of main water pipes, or for a second electricity company to enter the market and invest in a whole new set of electrical wires. These industries offer an example where, because of economies of scale, one producer can serve the entire market more efficiently than a number of smaller producers that would need to make duplicate physical capital investments.

A natural monopoly can also arise in smaller local markets for products that are difficult to transport. For example, cement production exhibits economies of scale, and the quantity of cement demanded in a local area may not be much larger than what a single plant can produce. Moreover, the costs of transporting cement over land are high, and so a cement plant in an area without access to water transportation may be a natural monopoly.

Control of a Physical Resource

Another type of natural monopoly occurs when a company has control of a scarce physical resource. In the U.S. economy, one historical example of this pattern occurred when ALCOA—the Aluminum Company of America—controlled most of the supply of bauxite, a key mineral used in making aluminum. Back in the 1930s, when ALCOA controlled most of the bauxite, other firms were simply unable to produce enough aluminum to compete.

As another example, the majority of global diamond production is controlled by DeBeers, a multi-national company that has mining and production operations in South Africa, Botswana, Namibia, and Canada. It also has exploration activities on four continents, while directing a worldwide distribution network of rough diamonds. Though in recent years they have experienced growing competition, their impact on the rough diamond market is still considerable.

Legal Monopoly

For some products, the government erects barriers to entry by prohibiting or limiting competition. Under U.S. law, no organization but the U.S. Postal Service is legally allowed to deliver first-class mail. Many states or cities have laws or regulations that allow households a choice of only one electric company, one water company, and one company to pick up the garbage. Most legal monopolies are considered utilities—products necessary for everyday life—that are socially beneficial to have. As a consequence, the government allows producers to become regulated monopolies, to insure that an appropriate amount of these products is provided to consumers. Additionally, legal monopolies are often subject to economies of scale, so it makes sense to allow only one provider.

Promoting Innovation

Innovation takes time and resources to achieve. Suppose a company invests in research and development and finds the cure for the common cold. In this world of near ubiquitous information, other companies could take the formula, produce the drug, and because they did not incur the costs of research and development (R&D), undercut the price of the company that discovered the drug. Given this possibility, many firms would choose not to invest in research and development, and as a result, the world would have less innovation. To prevent this from happening, the Constitution of the United States specifies in Article I, Section 8: “The Congress shall have Power . . . To Promote the Progress of Science and Useful Arts, by securing for limited Times to Authors and Inventors the Exclusive Right to their Writings and Discoveries.” Congress used this power to create the U.S. Patent and Trademark Office, as well as the U.S. Copyright Office. A patent gives the inventor the exclusive legal right to make, use, or sell the invention for a limited time; in the United States, exclusive patent rights last for 20 years. The idea is to provide limited monopoly power so that innovative firms can recoup their investment in R&D, but then to allow other firms to produce the product more cheaply once the patent expires.

A trademark is an identifying symbol or name for a particular good like Chiquita bananas, Chevrolet cars, or the Nike “swoosh” that appears on shoes and athletic gear. Roughly 1.9 million trademarks are registered with the U.S. government. A firm can renew a trademark over and over again, as long as it remains in active use.

A copyright, according to the U.S. Copyright Office, “is a form of protection provided by the laws of the United States for ‘original works of authorship’ including literary, dramatic, musical, architectural, cartographic, choreographic, pantomimic, pictorial, graphic, sculptural, and audiovisual creations.” No one can reproduce, display, or perform a copyrighted work without permission of the author. Copyright protection ordinarily lasts for the life of the author plus 70 years.

Roughly speaking, patent law covers inventions and copyright protects books, songs, and art. In certain areas, like the invention of new software, it has been unclear whether patent or copyright protection should apply. There is also a body of law known as trade secrets. Even if a company does not have a patent on an invention, competing firms are not allowed to steal their secrets. One famous trade secret is the formula for Coca-Cola, which is not protected under copyright or patent law, but is simply kept secret by the company.

Taken together, this combination of patents, trademarks, copyrights, and trade secret law is called intellectual property because it implies ownership over an idea, concept, or image, not a physical piece of property like a house or a car. Countries around the world have enacted laws to protect intellectual property although the time periods and exact provisions of such laws vary across countries. There are ongoing negotiations, both through the World Intellectual Property Organization (WIPO) and through international treaties, to bring greater harmony to the intellectual property laws of different countries to determine the extent to which patents and copyrights in one country will be respected in other countries.

Government limitations on competition used to be even more common in the United States. For most of the twentieth century, only one phone company—AT&T—was legally allowed to provide local and long distance service. From the 1930s to the 1970s, one set of federal regulations limited which destinations airlines could choose to fly to and what fares they could charge; another set of regulations limited the interest rates that banks could pay to depositors; yet another specified what trucking firms could charge customers.

What products are considered utilities depends, in part, on the available technology. Fifty years ago, local and long distance telephone service was provided over wires. It did not make much sense to have multiple companies building multiple systems of wiring across towns and across the country. AT&T lost its monopoly on long distance service when the technology for providing phone service changed from wires to microwave and satellite transmission, so that multiple firms could use the same transmission mechanism. The same thing happened to local service, especially in recent years, with the growth in cellular phone systems.

The combination of improvements in production technologies and a general sense that the markets could provide services adequately led to a wave of deregulation, starting in the late 1970s and continuing into the 1990s. This wave eliminated or reduced government restrictions on the firms that could enter, the prices that could be charged, and the quantities that could be produced in many industries, including telecommunications, airlines, trucking, banking, and electricity.

Around the world, from Europe to Latin America to Africa and Asia, many governments continue to control and limit competition in what those governments perceive to be key industries, including airlines, banks, steel companies, oil companies, and telephone companies.

Regulating Natural Monopolies

Most true monopolies today in the U.S. are regulated natural monopolies. A natural monopoly poses a difficult challenge for competition policy, because the structure of costs and demand seems to make competition unlikely or costly. A natural monopoly arises when average costs are declining over the range of production that satisfies market demand. This typically happens when fixed costs are large relative to variable costs. As a result, one firm is able to supply the total quantity demanded in the market at lower cost than two or more firms—so splitting up the natural monopoly would raise the average cost of production and force customers to pay more.

Public utilities, the companies that have traditionally provided water and electrical service across much of the United States, are leading examples of natural monopoly. It would make little sense to argue that a local water company should be broken up into several competing companies, each with its own separate set of pipes and water supplies. Installing four or five identical sets of pipes under a city, one for each water company, so that each household could choose its own water provider would be terribly costly. The same argument applies to the idea of having many competing companies for delivering electricity to homes, each with its own set of wires. Before the advent of wireless phones, the argument also applied to the idea of many different phone companies, each with its own set of phone wires running through the neighborhood.

The Choices in Regulating a Natural Monopoly

So what is the appropriate competition policy for a natural monopoly? Figure 5 illustrates the case of natural monopoly, with a market demand curve that cuts through the downward-sloping portion of the average cost curve. Points A, B, C, and F illustrate four of the main choices for regulation. Table 2 outlines the regulatory choices for dealing with a natural monopoly.

Regulatory Choices in Dealing with a Natural Monopoly

Figure 4 --A natural monopoly will maximize profits by producing at the quantity where marginal revenue (MR) equals marginal costs (MC) and by then looking to the market demand curve to see what price to charge for this quantity. This monopoly will produce at point A, with a quantity of 4 and a price of 9.3. If antitrust regulators split this company exactly in half, then each half would produce at point B, with average costs of 9.75 and output of 2. The regulators might require the firm to produce where marginal cost crosses the market demand curve at point C. However, if the firm is required to produce at a quantity of 8 and sell at a price of 3.5, the firm will suffer from losses. The most likely choice is point F, where the firm is required to produce a quantity of 6 and charge a price of 6.5.

Regulatory Choices in Dealing with Natural Monopoly(*Total Revenue is given by multiplying price and quantity. However, some of the price values in this table have been rounded for ease of presentation.)

The first possibility is to leave the natural monopoly alone. In this case, the monopoly will follow its normal approach to maximizing profits. It determines the quantity where MR = MC, which happens at point P at a quantity of 4. The firm then looks to point A on the demand curve to find that it can charge a price of 9.3 for that profit-maximizing quantity. Since the price is above the average cost curve, the natural monopoly would earn economic profits.

A second outcome arises if antitrust authorities decide to divide the company, so that the new firms can compete. As a simple example, imagine that the company is cut in half. Thus, instead of one large firm producing a quantity of 4, two half-size firms each produce a quantity of 2. Because of the declining average cost curve (AC), the average cost of production for each of the half-size companies each producing 2, as shown at point B, would be 9.75, while the average cost of production for a larger firm producing 4 would only be 7.75. Therefore, the economy would become less productively efficient since the good is being produced at a higher average cost. In a situation with a downward-sloping average cost curve, two smaller firms will always have higher average costs of production than one larger firm for any quantity of total output. In addition, the antitrust authorities must worry that splitting the natural monopoly into pieces may be only the start of their problems. If one of the two firms grows larger than the other, it will have lower average costs and may be able to drive its competitor out of the market. Alternatively, two firms in a market may discover subtle ways of coordinating their behavior and keeping prices high. Either way, the result will not be the greater competition that was desired.

A third alternative is that regulators may decide to set prices and quantities produced for this industry. The regulators will try to choose a point along the market demand curve that benefits both consumers and the broader social interest. Point C illustrates one tempting choice: the regulator requires that the firm produce the quantity of output where marginal cost crosses the demand curve at an output of 8, and charge the price of 3.5, which is equal to marginal cost at that point. This rule is appealing because it requires price to be set equal to marginal cost, which is what would occur in a perfectly competitive market, and it would assure consumers a higher quantity and lower price than at the monopoly choice A. In fact, efficient allocation of resources would occur at point C, since the value to the consumers of the last unit bought and sold in this market is equal to the marginal cost of producing it.

Attempting to bring about point C through force of regulation, however, runs into a severe difficulty. At point C, with an output of 8, a price of 3.5 is below the average cost of production, which is 5.7, and so if the firm charges a price of 3.5, it will be suffering losses. Unless the regulators or the government offer the firm an ongoing public subsidy (and there are numerous political problems with that option), the firm will lose money and go out of business.

Perhaps the most plausible option for the regulator is point F; that is, to set the price where AC crosses the demand curve at an output of 6 and a price of 6.5. This plan makes some sense at an intuitive level: let the natural monopoly charge enough to cover its average costs and earn a normal rate of profit, so that it can continue operating, but prevent the firm from raising prices and earning abnormally high monopoly profits, as it would at the monopoly choice A. Of course, determining this level of output and price with the political pressures, time constraints, and limited information of the real world is much harder than identifying the point on a graph. For more on the problems that can arise from a centrally determined price, see the discussion of price floors and price ceilings in Demand and Supply .

The Great Deregulation Experiment

Governments at all levels across the United States have regulated prices in a wide range of industries. In some cases, like water and electricity that have natural monopoly characteristics, there is some room in economic theory for such regulation. But once politicians are given a basis to intervene in markets and to choose prices and quantities, it is hard to know where to stop.

Doubts about Regulation of Prices and Quantities

Beginning in the 1970s, it became clear to policymakers of all political leanings that the existing price regulation was not working well. The United States carried out a great policy experiment—the deregulation discussed in Monopoly —removing government controls over prices and quantities produced in airlines, railroads, trucking, intercity bus travel, natural gas, and bank interest rates. The Clear it Up discusses the outcome of deregulation in one industry in particular—airlines.

What are the Results of Airline Deregulation?

Why did the pendulum swing in favor of deregulation? Consider the airline industry. In the early days of air travel, no airline could make a profit just by flying passengers. Airlines needed something else to carry and the Postal Service provided that something with airmail. So the first U.S. government regulation of the airline industry happened through the Postal Service when. In 1926 the Postmaster General began giving airlines permission to fly certain routes based on the needs of mail delivery—and the airlines took some passengers along for the ride. In 1934, the Postmaster General was charged by the antitrust authorities with colluding with the major airlines of that day to monopolize the nation’s airways. In 1938, the Civil Aeronautics Board (CAB) was created to regulate airfares and routes instead. For 40 years, from 1938 to 1978, the CAB approved all fares, controlled all entry and exit, and specified which airlines could fly which routes. There was zero entry of new airlines on the main routes across the country for 40 years because the CAB did not think it was necessary.

In 1978, the Airline Deregulation Act took the government out of the business of determining airfares and schedules. The new law shook up the industry. Famous old airlines like Pan American, Eastern, and Braniff went bankrupt and disappeared. Some new airlines like People Express were created—and then vanished.

The greater competition from deregulation reduced airfares by about one-third over the next two decades, saving consumers billions of dollars a year. The average flight used to take off with just half its seats full; now it is two-thirds full, which is far more efficient. Airlines have also developed hub-and-spoke systems, where planes all fly into a central hub city at a certain time and then depart. As a result, one can fly between any of the spoke cities with just one connection—and there is greater service to more cities than before deregulation. With lower fares and more service, the number of air passengers doubled from the late 1970s to the start of the 2000s—an increase that, in turn, doubled the number of jobs in the airline industry. Meanwhile, with the watchful oversight of government safety inspectors, commercial air travel has continued to grow safer over time.

The U.S. airline industry is far from perfect. For example, a string of mergers in recent years has raised concerns over how competition might be compromised.

One difficulty with government price regulation is what economists call regulatory capture. This occurs when the firms supposedly being regulated end up playing a large role in setting the regulations that they will follow. When the airline industry was being regulated, for example, it suggested appointees to the regulatory board, sent lobbyists to argue with the board, provided most of the information on which the board made decisions, and offered well-paid jobs to at least some of the people leaving the board. In this situation, consumers can easily end up being not very well represented by the regulators. The result of regulatory capture is that government price regulation can often become a way for existing competitors to work together to reduce output, keep prices high, and limit competition.

The Effects of Deregulation

Deregulation, both of airlines and of other industries, has its negatives. The greater pressure of competition led to entry and exit. When firms went bankrupt or contracted substantially in size, they laid off workers who had to find other jobs. Market competition is, after all, a full-contact sport.

A number of major accounting scandals involving prominent corporations such as Enron, Tyco International, and WorldCom led to the Sarbanes-Oxley Act in 2002. Sarbanes-Oxley was designed to increase confidence in financial information provided by public corporations to protect investors from accounting fraud.

The Great Recession which began in late 2007 and which the U.S. economy is still struggling to recover from was caused at least in part by a global financial crisis, which began in the United States. The key component of the crisis was the creation and subsequent failure of several types of unregulated financial assets, such as collateralized mortgage obligations (CMOs, a type of mortgage-backed security), and credit default swaps (CDSs, insurance contracts on assets like CMOs that provided a payoff even if the holder of the CDS did not own the CMO). Many of these assets were rated very safe by private credit rating agencies such as Standard & Poors, Moody’s, and Fitch.

The collapse of the markets for these assets precipitated the financial crisis and led to the failure of Lehman Brothers, a major investment bank, numerous large commercial banks, such as Wachovia, and even the Federal National Mortgage Corporation (Fannie Mae), which had to be nationalized—that is, taken over by the federal government. One response to the financial crisis was the Dodd-Frank Act, which attempted major reforms of the financial system. The legislation’s purpose, as noted on dodd-frank.com is:

To promote the financial stability of the United States by improving accountability and transparency in the financial system, to end “too big to fail,” to protect the American taxpayer by ending bailouts, [and] to protect consumers from abusive financial services practices. . .

We will explore the financial crisis and the Great Recession in more detail in the macroeconomic chapters of this book, but for now it should be clear that many Americans have grown disenchanted with deregulation, at least of financial markets.

All market-based economies operate against a background of laws and regulations, including laws about enforcing contracts, collecting taxes, and protecting health and the environment. The government policies discussed in this chapter—like blocking certain anticompetitive mergers, ending restrictive practices, imposing price cap regulation on natural monopolies, and deregulation—demonstrate the role of government to strengthen the incentives that come with a greater degree of competition.

Intimidating Potential Competition

Businesses have developed a number of schemes for creating barriers to entry by deterring potential competitors from entering the market. One method is known as predatory pricing, in which a firm uses the threat of sharp price cuts to discourage competition. Predatory pricing is a violation of U.S. antitrust law, but it is difficult to prove.

Consider a large airline that provides most of the flights between two particular cities. A new, small start-up airline decides to offer service between these two cities. The large airline immediately slashes prices on this route to the bone, so that the new entrant cannot make any money. After the new entrant has gone out of business, the incumbent firm can raise prices again.

After this pattern is repeated once or twice, potential new entrants may decide that it is not wise to try to compete. Small airlines often accuse larger airlines of predatory pricing: in the early 2000s, for example, ValuJet accused Delta of predatory pricing, Frontier accused United, and Reno Air accused Northwest. In late 2009, the American Booksellers Association, which represents independently owned and often smaller bookstores, accused Amazon, Wal-Mart, and Target of predatory pricing for selling new hardcover best-sellers at low prices.

In some cases, large advertising budgets can also act as a way of discouraging the competition. If the only way to launch a successful new national cola drink is to spend more than the promotional budgets of Coca-Cola and Pepsi Cola, not too many companies will try. A firmly established brand name can be difficult to dislodge.

Summing Up Barriers to Entry

Table 3 lists the barriers to entry that have been discussed here. This list is not exhaustive, since firms have proved to be highly creative in inventing business practices that discourage competition. When barriers to entry exist, perfect competition is no longer a reasonable description of how an industry works. When barriers to entry are high enough, monopoly can result.

How a Profit-Maximizing Monopoly Chooses Output and Price

Consider a monopoly firm, comfortably surrounded by barriers to entry so that it need not fear competition from other producers. How will this monopoly choose its profit-maximizing quantity of output, and what price will it charge? Profits for the monopolist, like any firm, will be equal to total revenues minus total costs. The pattern of costs for the monopoly can be analyzed within the same framework as the costs of a perfectly competitive firm—that is, by using total cost, fixed cost, variable cost, marginal cost, average cost, and average variable cost. However, because a monopoly faces no competition, its situation and its decision process will differ from that of a perfectly competitive firm.

Demand Curves Perceived by a Perfectly Competitive Firm and by a Monopoly

A perfectly competitive firm acts as a price taker, so its calculation of total revenue is made by taking the given market price and multiplying it by the quantity of output that the firm chooses. The demand curve as it is perceived by a perfectly competitive firm appears in Figure 6 (a). The flat perceived demand curve means that, from the viewpoint of the perfectly competitive firm, it could sell either a relatively low quantity like Ql or a relatively high quantity like Qh at the market price P.

The Perceived Demand Curve for a Perfect Competitor and a Monopolist

(a) A perfectly competitive firm perceives the demand curve that it faces to be flat. The flat shape means that the firm can sell either a low quantity (Ql) or a high quantity (Qh) at exactly the same price (P). (b) A monopolist perceives the demand curve that it faces to be the same as the market demand curve, which for most goods is downward-sloping. Thus, if the monopolist chooses a high level of output (Qh), it can charge only a relatively low price (Pl); conversely, if the monopolist chooses a low level of output (Ql), it can then charge a higher price (Ph). The challenge for the monopolist is to choose the combination of price and quantity that maximizes profits.

What is the Difference between Perceived Demand and Market Demand?

The demand curve as perceived by a perfectly competitive firm is not the overall market demand curve for that product. However, the firm’s demand curve as perceived by a monopoly is the same as the market demand curve. The reason for the difference is that each perfectly competitive firm perceives the demand for its products in a market that includes many other firms; in effect, the demand curve perceived by a perfectly competitive firm is a tiny slice of the entire market demand curve. In contrast, a monopoly perceives the demand for its product in a market where the monopoly is the only producer.

While a monopolist can charge any price for its product, that price is nonetheless constrained by demand for the firm’s product. No monopolist, even one that is thoroughly protected by high barriers to entry, can require consumers to purchase its product. Because the monopolist is the only firm in the market, its demand curve is the same as the market demand curve, which is, unlike that for a perfectly competitive firm, downward-sloping.

Figure 6 illustrates this situation. The monopolist can either choose a point like R with a low price (Pl) and high quantity (Qh), or a point like S with a high price (Ph) and a low quantity (Ql), or some intermediate point. Setting the price too high will result in a low quantity sold, and will not bring in much revenue. Conversely, setting the price too low may result in a high quantity sold, but because of the low price, it will not bring in much revenue either. The challenge for the monopolist is to strike a profit-maximizing balance between the price it charges and the quantity that it sells. But why isn’t the perfectly competitive firm’s demand curve also the market demand curve? See the following Clear it Up feature for the answer to this question.

What Defines the Market?

A monopoly is a firm that sells all or nearly all of the goods and services in a given market. But what defines the “market”?

In a famous 1947 case, the federal government accused the DuPont company of having a monopoly in the cellophane market, pointing out that DuPont produced 75% of the cellophane in the United States. DuPont countered that even though it had a 75% market share in cellophane, it had less than a 20% share of the “flexible packaging materials,” which includes all other moisture-proof papers, films, and foils. In 1956, after years of legal appeals, the U.S. Supreme Court held that the broader market definition was more appropriate, and the case against DuPont was dismissed.

Questions over how to define the market continue today. True, Microsoft in the 1990s had a dominant share of the software for computer operating systems, but in the total market for all computer software and services, including everything from games to scientific programs, the Microsoft share was only about 16% in 2000. The Greyhound bus company may have a near-monopoly on the market for intercity bus transportation, but it is only a small share of the market for intercity transportation if that market includes private cars, airplanes, and railroad service. DeBeers has a monopoly in diamonds, but it is a much smaller share of the total market for precious gemstones and an even smaller share of the total market for jewelry. A small town in the country may have only one gas station: is this gas station a “monopoly,” or does it compete with gas stations that might be five, 10, or 50 miles away?

In general, if a firm produces a product without close substitutes, then the firm can be considered a monopoly producer in a single market. But if buyers have a range of similar—even if not identical—options available from other firms, then the firm is not a monopoly. Still, arguments over whether substitutes are close or not close can be controversial.

The Inefficiency of Monopoly

Most people criticize monopolies because they charge too high a price, but what economists object to is that monopolies do not supply enough output to be allocatively efficient. To understand why a monopoly is inefficient, it is useful to compare it with the benchmark model of perfect competition.

Allocative efficiency is a social concept. It refers to producing the optimal quantity of some output, the quantity where the marginal benefit to society of one more unit just equals the marginal cost. The rule of profit maximization in a world of perfect competition was for each firm to produce the quantity of output where P = MC, where the price (P) is a measure of how much buyers value the good and the marginal cost (MC) is a measure of what marginal units cost society to produce. Following this rule assures allocative efficiency. If P > MC, then the marginal benefit to society (as measured by P) is greater than the marginal cost to society of producing additional units, and a greater quantity should be produced. But in the case of monopoly, price is always greater than marginal cost at the profit-maximizing level of output, as can be seen by looking back at Figure 6. Thus, consumers will suffer from a monopoly because a lower quantity will be sold in the market, at a higher price, than would have been the case in a perfectly competitive market.

The problem of inefficiency for monopolies often runs even deeper than these issues, and it also involves incentives for efficiency over longer periods of time. There are counterbalancing incentives here. On one side, firms may strive for new inventions and new intellectual property because they want to become monopolies and earn high profits—at least for a few years until the competition catches up. In this way, monopolies may come to exist because of competitive pressures on firms. However, once a barrier to entry is in place, a monopoly that does not need to fear competition can just produce the same old products in the same old way—while still ringing up a healthy rate of profit. John Hicks, who won the Nobel Prize for economics in 1972, wrote in 1935, “The best of all monopoly profits is a quiet life.” He did not mean the comment in a complimentary way. He meant that monopolies may bank their profits and slack off on trying to please their customers.

When AT&T provided all of the local and long-distance phone service in the United States, along with manufacturing most of the phone equipment, the payment plans and types of phones did not change much. The old joke was that you could have any color phone you wanted, as long as it was black. In 1982, AT&T was split by government litigation into a number of local phone companies, a long-distance phone company, and a phone equipment manufacturer. An explosion of innovation followed. Services like call waiting, caller ID, three-way calling, voice mail though the phone company, mobile phones, and wireless connections to the Internet all became available. A wide-range of payment plans was also offered. It was no longer true that all phones were black; instead, phones came in a variety of shapes and colors. The end of the telephone monopoly brought lower prices, a greater quantity of services, and also a wave of innovation aimed at attracting and pleasing customers.

A monopolist is not a price taker, because when it decides what quantity to produce, it also determines the market price. For a monopolist, total revenue is relatively low at low quantities of output, because not much is being sold. Total revenue is also relatively low at very high quantities of output, because a very high quantity will sell only at a low price. Thus, total revenue for a monopolist will start low, rise, and then decline. The marginal revenue for a monopolist from selling additional units will decline. Each additional unit sold by a monopolist will push down the overall market price, and as more units are sold, this lower price applies to more and more units.

The monopolist will select the profit-maximizing level of output where MR = MC, and then charge the price for that quantity of output as determined by the market demand curve. If that price is above average cost, the monopolist earns positive profits.

Monopolists are not productively efficient, because they do not produce at the minimum of the average cost curve. Monopolists are not allocatively efficient, because they do not produce at the quantity where P = MC. As a result, monopolists produce less, at a higher average cost, and charge a higher price than would a combination of firms in a perfectly competitive industry. Monopolists also may lack incentives for innovation, because they need not fear entry.

Monopolistic Competition and Oligopoly

Perfect competition and monopoly are at opposite ends of the competition spectrum. A perfectly competitive market has many firms selling identical products who all act as price takers in the face of the competition. If you recall, price takers are firms that have no market power. They simply have to take the market price as given.

Monopoly arises when a single firm sells a product for which there are no close substitutes. Microsoft, for instance, has been considered a monopoly because of its domination of the operating systems market.

What about the vast majority of real world firms and organizations that fall between these extremes, firms that could be described as imperfectly competitive? What determines their behavior? They have more influence over the price they charge than perfectly competitive firms, but not as much as a monopoly would. What will they do?

One type of imperfectly competitive market is called monopolistic competition. Monopolistically competitive markets feature a large number of competing firms, but the products that they sell are not identical. Consider, as an example, the Mall of America in Minnesota, the largest shopping mall in the United States. In 2010, the Mall of America had 24 stores that sold women’s “ready-to-wear” clothing (like Ann Taylor and Coldwater Creek), another 50 stores that sold clothing for both men and women (like Banana Republic, J. Crew, and Nordstrom’s), plus 14 more stores that sold women’s specialty clothing (like Motherhood Maternity and Victoria’s Secret). Most of the markets that consumers encounter at the retail level are monopolistically competitive.

The other type of imperfectly competitive market is oligopoly. Oligopolistic markets are those dominated by a small number of firms. Commercial aircraft provides a good example: Boeing and Airbus each produce slightly less than 50% of the large commercial aircraft in the world. Another example is the U.S. soft drink industry, which is dominated by Coca-Cola and Pepsi. Oligopolies are characterized by high barriers to entry with firms choosing output, pricing, and other decisions strategically based on the decisions of the other firms in the market. In this chapter, we first explore how monopolistically competitive firms will choose their profit-maximizing level of output. We will then discuss oligopolistic firms, which face two conflicting temptations: to collaborate as if they were a single monopoly, or to individually compete to gain profits by expanding output levels and cutting prices. Oligopolistic markets and firms can also take on elements of monopoly and of perfect competition.

Visit the Organization of the Petroleum Exporting Countries website and learn more about its history and how it defines itself.

Video: Oligopolies and Game Theory

Monopolistic Competition

Monopolistic competition involves many firms competing against each other, but selling products that are distinctive in some way. Examples include stores that sell different styles of clothing; restaurants or grocery stores that sell different kinds of food; and even products like golf balls or beer that may be at least somewhat similar but differ in public perception because of advertising and brand names. When products are distinctive, each firm has a mini-monopoly on its particular style or flavor or brand name. However, firms producing such products must also compete with other styles and flavors and brand names. The term “monopolistic competition” captures this mixture of mini-monopoly and tough competition, and the following Clear It Up feature introduces its derivation.

Differentiated Products

A firm can try to make its products different from those of its competitors in several ways: physical aspects of the product, location from which the product is sold, intangible aspects of the product, and perceptions of the product. Products that are distinctive in one of these ways are called differentiated products.

Physical aspects of a product include all the phrases you hear in advertisements: unbreakable bottle, nonstick surface, freezer-to-microwave, non-shrink, extra spicy, newly redesigned for your comfort. The location of a firm can also create a difference between producers. For example, a gas station located at a heavily traveled intersection can probably sell more gas, because more cars drive by that corner. A supplier to an automobile manufacturer may find that it is an advantage to locate close to the car factory.

Intangible aspects can differentiate a product, too. Some intangible aspects may be promises like a guarantee of satisfaction or money back, a reputation for high quality, services like free delivery, or offering a loan to purchase the product. Finally, product differentiation may occur in the minds of buyers. For example, many people could not tell the difference in taste between common varieties of beer or cigarettes if they were blindfolded. However, because of past habits and advertising, they have strong preferences for certain brands. Advertising can play a role in shaping these intangible preferences.

The concept of differentiated products is closely related to the degree of variety that is available. If everyone in the economy wore only blue jeans, ate only white bread, and drank only tap water, then the markets for clothing, food, and drink would be much closer to perfectly competitive. The variety of styles, flavors, locations, and characteristics creates product differentiation and monopolistic competition.

Perceived Demand for a Monopolistic Competitor

A monopolistically competitive firm perceives a demand for its goods that is an intermediate case between monopoly and competition. Figure 7 offers a reminder that the demand curve as faced by a perfectly competitive firm is perfectly elastic or flat, because the perfectly competitive firm can sell any quantity it wishes at the prevailing market price. In contrast, the demand curve, as faced by a monopolist, is the market demand curve, since a monopolist is the only firm in the market, and hence is downward sloping.

Perceived Demand for Firms in Different Competitive Settings

The demand curve faced by a perfectly competitive firm is perfectly elastic, meaning it can sell all the output it wishes at the prevailing market price. The demand curve faced by a monopoly is the market demand. It can sell more output only by decreasing the price it charges. The demand curve faced by a monopolistically competitive firm falls in between.

The demand curve as faced by a monopolistic competitor is not flat, but rather downward-sloping, which means that the monopolistic competitor can raise its price without losing all of its customers or lower the price and gain more customers. Since there are substitutes, the demand curve facing a monopolistically competitive firm is more elastic than that of a monopoly where there are no close substitutes. If a monopolist raises its price, some consumers will choose not to purchase its product—but they will then need to buy a completely different product. However, when a monopolistic competitor raises its price, some consumers will choose not to purchase the product at all, but others will choose to buy a similar product from another firm. If a monopolistic competitor raises its price, it will not lose as many customers as would a perfectly competitive firm, but it will lose more customers than would a monopoly that raised its prices.

At a glance, the demand curves faced by a monopoly and by a monopolistic competitor look similar—that is, they both slope down. But the underlying economic meaning of these perceived demand curves is different, because a monopolist faces the market demand curve and a monopolistic competitor does not. Rather, a monopolistically competitive firm’s demand curve is but one of many firms that make up the “before” market demand curve. Are you following? If so, how would you categorize the market for golf balls?

How a Monopolistic Competitor Chooses Price and Quantity

The monopolistically competitive firm decides on its profit-maximizing quantity and price in much the same way as a monopolist. A monopolistic competitor, like a monopolist, faces a downward-sloping demand curve, and so it will choose some combination of price and quantity along its perceived demand curve.

To maximize profits, the Authentic Chinese Pizza shop would choose a quantity where marginal revenue equals marginal cost, or Q where MR = MC. Here it would choose a quantity of 40 and a price of $16.

The combinations of price and quantity at each point on the demand curve can be multiplied to calculate the total revenue that the firm would receive, which is shown in the third column of Table 4. The fourth column, marginal revenue, is calculated as the change in total revenue divided by the change in quantity. The final columns of Table 4 show total cost, marginal cost, and average cost. As always, marginal cost is calculated by dividing the change in total cost by the change in quantity, while average cost is calculated by dividing total cost by quantity.

How a Monopolistic Competitor Determines How Much to Produce and at What Price

The process by which a monopolistic competitor chooses its profit-maximizing quantity and price resembles closely a monopoly's decision making process. First, the firm selects the profit-maximizing quantity to produce. Then the firm decides what price to charge for that quantity.

Step 1. The monopolistic competitor determines its profit-maximizing level of output. In this case, the Authentic Chinese Pizza company will determine the profit-maximizing quantity to produce by considering its marginal revenues and marginal costs. Two scenarios are possible: If the firm is producing at a quantity of output where marginal revenue exceeds marginal cost, then the firm should keep expanding production, because each marginal unit is adding to profit by bringing in more revenue than its cost. In this way, the firm will produce up to the quantity where MR = MC. If the firm is producing at a quantity where marginal costs exceed marginal revenue, then each marginal unit is costing more than the revenue it brings in, and the firm will increase its profits by reducing the quantity of output until MR = MC.

In this example, MR and MC intersect at a quantity of 40, which is the profit-maximizing level of output for the firm.

Step 2. The monopolistic competitor decides what price to charge. When the firm has determined its profit-maximizing quantity of output, it can then look to its perceived demand curve to find out what it can charge for that quantity of output. On the graph, this process can be shown as a vertical line reaching up through the profit-maximizing quantity until it hits the firm’s perceived demand curve. For Authentic Chinese Pizza, it should charge a price of $16 per pizza for a quantity of 40.

Once the firm has chosen price and quantity, it is in a position to calculate total revenue, total cost, and profit. At a quantity of 40, the price of $16 lies above the average cost curve, so the firm is making economic profits. From Table 4 we can see that, at an output of 40, the firm’s total revenue is $640 and its total cost is $580, so profits are $60. In Figure 5, the firm’s total revenues are the rectangle with the quantity of 40 on the horizontal axis and the price of $16 on the vertical axis. The firm’s total costs are the light shaded rectangle with the same quantity of 40 on the horizontal axis but the average cost of $14.50 on the vertical axis. Profits are total revenues minus total costs, which is the shaded area above the average cost curve.

Although the process by which a monopolistic competitor makes decisions about quantity and price is similar to the way in which a monopolist makes such decisions, two differences are worth remembering. First, although both a monopolist and a monopolistic competitor face downward-sloping demand curves, the monopolist’s perceived demand curve is the market demand curve, while the perceived demand curve for a monopolistic competitor is based on the extent of its product differentiation and how many competitors it faces. Second, a monopolist is surrounded by barriers to entry and need not fear entry, but a monopolistic competitor who earns profits must expect the entry of firms with similar, but differentiated products.

Monopolistic Competitors and Entry

If one monopolistic competitor earns positive economic profits, other firms will be tempted to enter the market. A gas station with a great location must worry that other gas stations might open across the street or down the road—and perhaps the new gas stations will sell coffee or have a carwash or some other attraction to lure customers. A successful restaurant with a unique barbecue sauce must be concerned that other restaurants will try to copy the sauce or offer their own unique recipes. A laundry detergent with a great reputation for quality must be concerned that other competitors may seek to build their own reputations.

The entry of other firms into the same general market (like gas, restaurants, or detergent) shifts the demand curve faced by a monopolistically competitive firm. As more firms enter the market, the quantity demanded at a given price for any particular firm will decline, and the firm’s perceived demand curve will shift to the left. As a firm’s perceived demand curve shifts to the left, its marginal revenue curve will shift to the left, too. The shift in marginal revenue will change the profit-maximizing quantity that the firm chooses to produce, since marginal revenue will then equal marginal cost at a lower quantity.

Figure 9 (a) shows a situation in which a monopolistic competitor was earning a profit with its original perceived demand curve (D 0 ). The intersection of the marginal revenue curve (MR 0 ) and marginal cost curve (MC) occurs at point S, corresponding to quantity Q 0 , which is associated on the demand curve at point T with price P 0 . The combination of price P 0 and quantity Q 0 lies above the average cost curve, which shows that the firm is earning positive economic profits.

Monopolistic Competition, Entry, and Exit

(a) At P 0 and Q 0 , the monopolistically competitive firm shown in this figure is making a positive economic profit. This is clear because if you follow the dotted line above Q 0 , you can see that price is above average cost. Positive economic profits attract competing firms to the industry, driving the original firm’s demand down to D 1 . At the new equilibrium quantity (P 1 , Q 1 ), the original firm is earning zero economic profits, and entry into the industry ceases. In (b) the opposite occurs. At P 0 and Q 0 , the firm is losing money. If you follow the dotted line above Q 0 , you can see that average cost is above price. Losses induce firms to leave the industry. When they do, demand for the original firm rises to D 1 , where once again the firm is earning zero economic profit.

Unlike a monopoly, with its high barriers to entry, a monopolistically competitive firm with positive economic profits will attract competition. When another competitor enters the market, the original firm’s perceived demand curve shifts to the left, from D 0 to D 1 , and the associated marginal revenue curve shifts from MR 0 to MR 1 . The new profit-maximizing output is Q 1 , because the intersection of the MR 1 and MC now occurs at point U. Moving vertically up from that quantity on the new demand curve, the optimal price is at P 1 .

As long as the firm is earning positive economic profits, new competitors will continue to enter the market, reducing the original firm’s demand and marginal revenue curves. The long run equilibrium is shown in the figure at point V, where the firm’s perceived demand curve touches the average cost curve. When price is equal to average cost, economic profits are zero. Thus, although a monopolistically competitive firm may earn positive economic profits in the short term, the process of new entry will drive down economic profits to zero in the long run. Remember that zero economic profit is not equivalent to zero accounting profit. A zero economic profit means the firm’s accounting profit is equal to what its resources could earn in their next best use. Figure 9 (b) shows the reverse situation, where a monopolistically competitive firm is originally losing money. The adjustment to long-run equilibrium is analogous to the previous example. The economic losses lead to firms exiting, which will result in increased demand for this particular firm, and consequently lower losses. Firms exit up to the point where there are no more losses in this market, for example when the demand curve touches the average cost curve, as in point Z.

Monopolistic competitors can make an economic profit or loss in the short run, but in the long run, entry and exit will drive these firms toward a zero economic profit outcome. However, the zero economic profit outcome in monopolistic competition looks different from the zero economic profit outcome in perfect competition in several ways relating both to efficiency and to variety in the market.

Monopolistic Competition and Efficiency

The long-term result of entry and exit in a perfectly competitive market is that all firms end up selling at the price level determined by the lowest point on the average cost curve. This outcome is why perfect competition displays productive efficiency: goods are being produced at the lowest possible average cost. However, in monopolistic competition, the end result of entry and exit is that firms end up with a price that lies on the downward-sloping portion of the average cost curve, not at the very bottom of the AC curve. Thus, monopolistic competition will not be productively efficient.

In a perfectly competitive market, each firm produces at a quantity where price is set equal to marginal cost, both in the short run and in the long run. This outcome is why perfect competition displays allocative efficiency: the social benefits of additional production, as measured by the marginal benefit, which is the same as the price, equal the marginal costs to society of that production. In a monopolistically competitive market, the rule for maximizing profit is to set MR = MC—and price is higher than marginal revenue, not equal to it because the demand curve is downward sloping. When P > MC, which is the outcome in a monopolistically competitive market, the benefits to society of providing additional quantity, as measured by the price that people are willing to pay, exceed the marginal costs to society of producing those units. A monopolistically competitive firm does not produce more, which means that society loses the net benefit of those extra units. This is the same argument we made about monopoly, but in this case to a lesser degree. Thus, a monopolistically competitive industry will produce a lower quantity of a good and charge a higher price for it than would a perfectly competitive industry.

The Benefits of Variety and Product Differentiation

Even though monopolistic competition does not provide productive efficiency or allocative efficiency, it does have benefits of its own. Product differentiation is based on variety and innovation. Many people would prefer to live in an economy with many kinds of clothes, foods, and car styles; not in a world of perfect competition where everyone will always wear blue jeans and white shirts, eat only spaghetti with plain red sauce, and drive an identical model of car. Many people would prefer to live in an economy where firms are struggling to figure out ways of attracting customers by methods such as friendlier service, free delivery, guarantees of quality, variations on existing products, and a better shopping experience.

Economists have struggled, with only partial success, to address the question of whether a market-oriented economy produces the optimal amount of variety. Critics of market-oriented economies argue that society does not really need dozens of different athletic shoes or breakfast cereals or automobiles. They argue that much of the cost of creating such a high degree of product differentiation, and then of advertising and marketing this differentiation, is socially wasteful—that is, most people would be just as happy with a smaller range of differentiated products produced and sold at a lower price. Defenders of a market-oriented economy respond that if people do not want to buy differentiated products or highly advertised brand names, no one is forcing them to do so. Moreover, they argue that consumers benefit substantially when firms seek short-term profits by providing differentiated products. This controversy may never be fully resolved, in part because deciding on the optimal amount of variety is very difficult, and in part because the two sides often place different values on what variety means for consumers.

How Does Advertising Impact Monopolistic Competition?

The U.S. economy spent about $139.5 billion on advertising in 2012 according to Kantar Media Reports. Roughly one-third of this was television advertising, and another third was divided roughly equally between Internet, newspapers, and radio. The remaining third was divided up between direct mail, magazines, telephone directory yellow pages, billboards, and other miscellaneous sources. More than 500,000 workers held jobs in the advertising industry.

Advertising is all about explaining to people, or making people believe, that the products of one firm are differentiated from the products of another firm. In the framework of monopolistic competition, there are two ways to conceive of how advertising works: either advertising causes a firm’s perceived demand curve to become more inelastic (that is, it causes the perceived demand curve to become steeper); or advertising causes demand for the firm’s product to increase (that is, it causes the firm’s perceived demand curve to shift to the right). In either case, a successful advertising campaign may allow a firm to sell either a greater quantity or to charge a higher price, or both, and thus increase its profits.

Monopolistic competition refers to a market where many firms sell differentiated products. Differentiated products can arise from characteristics of the good or service, location from which the product is sold, intangible aspects of the product, and perceptions of the product.

The perceived demand curve for a monopolistically competitive firm is downward-sloping, which shows that it is a price maker and chooses a combination of price and quantity. However, the perceived demand curve for a monopolistic competitor is more elastic than the perceived demand curve for a monopolist, because the monopolistic competitor has direct competition, unlike the pure monopolist. A profit-maximizing monopolistic competitor will seek out the quantity where marginal revenue is equal to marginal cost. The monopolistic competitor will produce that level of output and charge the price that is indicated by the firm’s demand curve.

If the firms in a monopolistically competitive industry are earning economic profits, the industry will attract entry until profits are driven down to zero in the long run. If the firms in a monopolistically competitive industry are suffering economic losses, then the industry will experience exit of firms until economic profits are driven up to zero in the long run.

A monopolistically competitive firm is not productively efficient because it does not produce at the minimum of its average cost curve. A monopolistically competitive firm is not allocatively efficient because it does not produce where P = MC, but instead produces where P > MC. Thus, a monopolistically competitive firm will tend to produce a lower quantity at a higher cost and to charge a higher price than a perfectly competitive firm.

Monopolistically competitive industries do offer benefits to consumers in the form of greater variety and incentives for improved products and services. There is some controversy over whether a market-oriented economy generates too much variety.

Many purchases that individuals make at the retail level are produced in markets that are neither perfectly competitive, monopolies, nor monopolistically competitive. Rather, they are oligopolies. Oligopoly arises when a small number of large firms have all or most of the sales in an industry. Examples of oligopoly abound and include the auto industry, cable television, and commercial air travel. Oligopolistic firms are like cats in a bag. They can either scratch each other to pieces or cuddle up and get comfortable with one another. If oligopolists compete hard, they may end up acting very much like perfect competitors, driving down costs and leading to zero profits for all. If oligopolists collude with each other, they may effectively act like a monopoly and succeed in pushing up prices and earning consistently high levels of profit. Oligopolies are typically characterized by mutual interdependence where various decisions such as output, price, advertising, and so on, depend on the decisions of the other firm(s). Analyzing the choices of oligopolistic firms about pricing and quantity produced involves considering the pros and cons of competition versus collusion at a given point in time.

Why Do Oligopolies Exist?

A combination of the barriers to entry that create monopolies and the product differentiation that characterizes monopolistic competition can create the setting for an oligopoly. For example, when a government grants a patent for an invention to one firm, it may create a monopoly. When the government grants patents to, for example, three different pharmaceutical companies that each has its own drug for reducing high blood pressure, those three firms may become an oligopoly.

Similarly, a natural monopoly will arise when the quantity demanded in a market is only large enough for a single firm to operate at the minimum of the long-run average cost curve. In such a setting, the market has room for only one firm, because no smaller firm can operate at a low enough average cost to compete, and no larger firm could sell what it produced given the quantity demanded in the market.

Quantity demanded in the market may also be two or three times the quantity needed to produce at the minimum of the average cost curve. This means that the market would have room for only two or three oligopoly firms (and they need not produce differentiated products). Again, smaller firms would have higher average costs and be unable to compete, while additional large firms would produce such a high quantity that they would not be able to sell it at a profitable price. This combination of economies of scale and market demand creates the barrier to entry, which led to the Boeing-Airbus oligopoly for large passenger aircraft.

The product differentiation at the heart of monopolistic competition can also play a role in creating oligopoly. For example, firms may need to reach a certain minimum size before they are able to spend enough on advertising and marketing to create a recognizable brand name. The problem in competing with, say, Coca-Cola or Pepsi is not that producing fizzy drinks is technologically difficult, but rather that creating a brand name and marketing effort to equal Coke or Pepsi is an enormous task.

Collusion or Competition?

When oligopoly firms in a certain market decide what quantity to produce and what price to charge, they face a temptation to act as if they were a monopoly. By acting together, oligopolistic firms can hold down industry output, charge a higher price, and divide up the profit among themselves. When firms act together in this way to reduce output and keep prices high, it is called collusion. A group of firms that have a formal agreement to collude to produce the monopoly output and sell at the monopoly price is called a cartel. See the following Clear It Up feature for a more in-depth analysis of the difference between the two.

Collusion Versus Cartels: How Can I tell Which is Which?

In the United States, as well as many other countries, it is illegal for firms to collude since collusion is anti-competitive behavior, which is a violation of antitrust law. Both the Antitrust Division of the Justice Department and the Federal Trade Commission have responsibilities for preventing collusion in the United States.

The problem of enforcement is finding hard evidence of collusion. Cartels are formal agreements to collude. Because cartel agreements provide evidence of collusion, they are rare in the United States. Instead, most collusion is tacit, where firms implicitly reach an understanding that competition is bad for profits.

The desire of businesses to avoid competing so that they can instead raise the prices that they charge and earn higher profits has been well understood by economists. Adam Smith wrote in Wealth of Nations in 1776, “People of the same trade seldom meet together, even for merriment and diversion, but the conversation ends in a conspiracy against the public, or in some contrivance to raise prices.”

Even when oligopolists recognize that they would benefit as a group by acting like a monopoly, each individual oligopoly faces a private temptation to produce just a slightly higher quantity and earn slightly higher profit—while still counting on the other oligopolists to hold down their production and keep prices high. If at least some oligopolists give in to this temptation and start producing more, then the market price will fall. Indeed, a small handful of oligopoly firms may end up competing so fiercely that they all end up earning zero economic profits—as if they were perfect competitors.

The Prisoner’s Dilemma

Because of the complexity of oligopoly, which is the result of mutual interdependence among firms, there is no single, generally-accepted theory of how oligopolies behave, in the same way that we have theories for all the other market structures. Instead, economists use game theory, a branch of mathematics that analyzes situations in which players must make decisions and then receive payoffs based on what other players decide to do. Game theory has found widespread applications in the social sciences, as well as in business, law, and military strategy.

The prisoner’s dilemma is a scenario in which the gains from cooperation are larger than the rewards from pursuing self-interest. It applies well to oligopoly. The story behind the prisoner’s dilemma goes like this:

Two co-conspiratorial criminals are arrested. When they are taken to the police station, they refuse to say anything and are put in separate interrogation rooms. Eventually, a police officer enters the room where Prisoner A is being held and says: “You know what? Your partner in the other room is confessing. So your partner is going to get a light prison sentence of just one year, and because you’re remaining silent, the judge is going to stick you with eight years in prison. Why don’t you get smart? If you confess, too, we’ll cut your jail time down to five years, and your partner will get five years, also.” Over in the next room, another police officer is giving exactly the same speech to Prisoner B. What the police officers do not say is that if both prisoners remain silent, the evidence against them is not especially strong, and the prisoners will end up with only two years in jail each.

The game theory situation facing the two prisoners is shown in Table 5. To understand the dilemma, first consider the choices from Prisoner A’s point of view. If A believes that B will confess, then A ought to confess, too, so as to not get stuck with the eight years in prison. But if A believes that B will not confess, then A will be tempted to act selfishly and confess, so as to serve only one year. The key point is that A has an incentive to confess regardless of what choice B makes! B faces the same set of choices, and thus will have an incentive to confess regardless of what choice A makes. Confess is considered the dominant strategy or the strategy an individual (or firm) will pursue regardless of the other individual’s (or firm’s) decision. The result is that if prisoners pursue their own self-interest, both are likely to confess, and end up doing a total of 10 years of jail time between them.

The game is called a dilemma because if the two prisoners had cooperated by both remaining silent, they would only have had to serve a total of four years of jail time between them. If the two prisoners can work out some way of cooperating so that neither one will confess, they will both be better off than if they each follow their own individual self-interest, which in this case leads straight into longer jail terms.

The Oligopoly Version of the Prisoner’s Dilemma

The members of an oligopoly can face a prisoner’s dilemma, also. If each of the oligopolists cooperates in holding down output, then high monopoly profits are possible. Each oligopolist, however, must worry that while it is holding down output, other firms are taking advantage of the high price by raising output and earning higher profits. Table 6 shows the prisoner’s dilemma for a two-firm oligopoly—known as a duopoly. If Firms A and B both agree to hold down output, they are acting together as a monopoly and will each earn $1,000 in profits. However, both firms’ dominant strategy is to increase output, in which case each will earn $400 in profits.

Can the two firms trust each other? Consider the situation of Firm A: If A thinks that B will cheat on their agreement and increase output, then A will increase output, too, because for A the profit of $400 when both firms increase output (the bottom right-hand choice in Table 6) is better than a profit of only $200 if A keeps output low and B raises output (the upper right-hand choice in the table). If A thinks that B will cooperate by holding down output, then A may seize the opportunity to earn higher profits by raising output. After all, if B is going to hold down output, then A can earn $1,500 in profits by expanding output (the bottom left-hand choice in the table) compared with only $1,000 by holding down output as well (the upper left-hand choice in the table).

Thus, Firm A will reason that it makes sense to expand output if B holds down output and that it also makes sense to expand output if B raises output. Again, B faces a parallel set of decisions.

The result of this prisoner’s dilemma is often that even though A and B could make the highest combined profits by cooperating in producing a lower level of output and acting like a monopolist, the two firms may well end up in a situation where they each increase output and earn only $400 each in profits.

What is the Lysine Cartel?

Lysine, a $600 million-a-year industry, is an amino acid used by farmers as a feed additive to ensure the proper growth of swine and poultry. The primary U.S. producer of lysine is Archer Daniels Midland (ADM), but several other large European and Japanese firms are also in this market. For a time in the first half of the 1990s, the world’s major lysine producers met together in hotel conference rooms and decided exactly how much each firm would sell and what it would charge. The U.S. Federal Bureau of Investigation (FBI), however, had learned of the cartel and placed wire taps on a number of their phone calls and meetings.

From FBI surveillance tapes, following is a comment that Terry Wilson, president of the corn processing division at ADM, made to the other lysine producers at a 1994 meeting in Mona, Hawaii:

I wanna go back and I wanna say something very simple. If we’re going to trust each other, okay, and if I’m assured that I’m gonna get 67,000 tons by the year’s end, we’re gonna sell it at the prices we agreed to . . . The only thing we need to talk about there because we are gonna get manipulated by these [expletive] buyers—they can be smarter than us if we let them be smarter. . . . They [the customers] are not your friend. They are not my friend. And we gotta have ‘em, but they are not my friends. You are my friend. I wanna be closer to you than I am to any customer. Cause you can make us ... money. ... And all I wanna tell you again is let’s—let’s put the prices on the board. Let’s all agree that’s what we’re gonna do and then walk out of here and do it.

The price of lysine doubled while the cartel was in effect. Confronted by the FBI tapes, Archer Daniels Midland pled guilty in 1996 and paid a fine of $100 million. A number of top executives, both at ADM and other firms, later paid fines of up to $350,000 and were sentenced to 24–30 months in prison.

In another one of the FBI recordings, the president of Archer Daniels Midland told an executive from another competing firm that ADM had a slogan that, in his words, had “penetrated the whole company.” The company president stated the slogan this way: “Our competitors are our friends. Our customers are the enemy.” That slogan could stand as the motto of cartels everywhere.

How to Enforce Cooperation

How can parties who find themselves in a prisoner’s dilemma situation avoid the undesired outcome and cooperate with each other? The way out of a prisoner’s dilemma is to find a way to penalize those who do not cooperate.

Perhaps the easiest approach for colluding oligopolists, as you might imagine, would be to sign a contract with each other that they will hold output low and keep prices high. If a group of U.S. companies signed such a contract, however, it would be illegal. Certain international organizations, like the nations that are members of the Organization of Petroleum Exporting Countries (OPEC), have signed international agreements to act like a monopoly, hold down output, and keep prices high so that all of the countries can make high profits from oil exports. Such agreements, however, because they fall in a gray area of international law, are not legally enforceable. If Nigeria, for example, decides to start cutting prices and selling more oil, Saudi Arabia cannot sue Nigeria in court and force it to stop.

Because oligopolists cannot sign a legally enforceable contract to act like a monopoly, the firms may instead keep close tabs on what other firms are producing and charging. Alternatively, oligopolists may choose to act in a way that generates pressure on each firm to stick to its agreed quantity of output.

One example of the pressure these firms can exert on one another is the kinked demand curve, in which competing oligopoly firms commit to match price cuts, but not price increases. This situation is shown in Figure 10. Say that an oligopoly airline has agreed with the rest of a cartel to provide a quantity of 10,000 seats on the New York to Los Angeles route, at a price of $500. This choice defines the kink in the firm’s perceived demand curve. The reason that the firm faces a kink in its demand curve is because of how the other oligopolists react to changes in the firm’s price. If the oligopoly decides to produce more and cut its price, the other members of the cartel will immediately match any price cuts—and therefore, a lower price brings very little increase in quantity sold.

If one firm cuts its price to $300, it will be able to sell only 11,000 seats. However, if the airline seeks to raise prices, the other oligopolists will not raise their prices, and so the firm that raised prices will lose a considerable share of sales. For example, if the firm raises its price to $550, its sales drop to 5,000 seats sold. Thus, if oligopolists always match price cuts by other firms in the cartel, but do not match price increases, then none of the oligopolists will have a strong incentive to change prices, since the potential gains are minimal. This strategy can work like a silent form of cooperation, in which the cartel successfully manages to hold down output, increase price, and share a monopoly level of profits even without any legally enforceable agreement.

A Kinked Demand Curve

Consider a member firm in an oligopoly cartel that is supposed to produce a quantity of 10,000 and sell at a price of $500. The other members of the cartel can encourage this firm to honor its commitments by acting so that the firm faces a kinked demand curve. If the oligopolist attempts to expand output and reduce price slightly, other firms also cut prices immediately—so if the firm expands output to 11,000, the price per unit falls dramatically, to $300. On the other side, if the oligopoly attempts to raise its price, other firms will not do so, so if the firm raises its price to $550, its sales decline sharply to 5,000. Thus, the members of a cartel can discipline each other to stick to the pre-agreed levels of quantity and price through a strategy of matching all price cuts but not matching any price increases.

Many real-world oligopolies, prodded by economic changes, legal and political pressures, and the egos of their top executives, go through episodes of cooperation and competition. If oligopolies could sustain cooperation with each other on output and pricing, they could earn profits as if they were a single monopoly. However, each firm in an oligopoly has an incentive to produce more and grab a bigger share of the overall marke. When firms start behaving in this way, the market outcome in terms of prices and quantity can be similar to that of a highly competitive market.

Tradeoffs of Imperfect Competition

Monopolistic competition is probably the single most common market structure in the U.S. economy. It provides powerful incentives for innovation, as firms seek to earn profits in the short run, while entry assures that firms do not earn economic profits in the long run. However, monopolistically competitive firms do not produce at the lowest point on their average cost curves. In addition, the endless search to impress consumers through product differentiation may lead to excessive social expenses on advertising and marketing.

Oligopoly is probably the second most common market structure. When oligopolies result from patented innovations or from taking advantage of economies of scale to produce at low average cost, they may provide considerable benefit to consumers. Oligopolies are often buffeted by significant barriers to entry, which enable the oligopolists to earn sustained profits over long periods of time. Oligopolists also do not typically produce at the minimum of their average cost curves. When they lack vibrant competition, they may lack incentives to provide innovative products and high-quality service.

The task of public policy with regard to competition is to sort through these multiple realities, attempting to encourage behavior that is beneficial to the broader society and to discourage behavior that only adds to the profits of a few large companies, with no corresponding benefit to consumers.

An oligopoly is a situation where a few firms sell most or all of the goods in a market. Oligopolists earn their highest profits if they can band together as a cartel and act like a monopolist by reducing output and raising price. Since each member of the oligopoly can benefit individually from expanding output, such collusion often breaks down—especially since explicit collusion is illegal.

The prisoner’s dilemma is an example of game theory. It shows how, in certain situations, all sides can benefit from cooperative behavior rather than self-interested behavior. However, the challenge for the parties is to find ways to encourage cooperative behavior.

More than Cooking, Heating, and Cooling

If you live in the United States, there is a slightly better than 50–50 chance your home is heated and cooled using natural gas. You may even use natural gas for cooking. However, those uses are not the primary uses of natural gas in the U.S. In 2012, according to the U.S. Energy Information Administration, home heating, cooling, and cooking accounted for just 18% of natural gas usage. What accounts for the rest? The greatest uses for natural gas are the generation of electric power (39%) and in industry (30%). Together these three uses for natural gas touch many areas of our lives, so why would there be any opposition to a merger of two natural gas firms? After all, a merger could mean increased efficiencies and reduced costs to people like you and me.

In October 2011, Kinder Morgan and El Paso Corporation, two natural gas firms, announced they were merging. The announcement stated the combined firm would link “nearly every major production region with markets,” cut costs by “eliminating duplication in pipelines and other assets,” and that “the savings could be passed on to consumers.”

The objection? The $21.1 billion deal would give Kinder Morgan control of more than 80,000 miles of pipeline, making the new firm the third largest energy producer in North America. As the third largest energy producer, policymakers and the public wondered whether the cost savings really would be passed on to consumers, or would the merger give Kinder Morgan a strong oligopoly position in the natural gas marketplace?

What should the balance be between corporate size and a larger number of competitors in a marketplace? What role should the government play? What did the Federal Trade Commission (FTC) decide on the Kinder Morgan / El Paso Corporation merger? After careful examination, federal officials decided there was only one area of significant overlap that might provide the merged firm with strong market power. The FTC approved the merger, provided Kinder Morgan divest itself of the overlap area. Tallgrass purchased Kinder Morgan Interstate Gas Transmission, Trailblazer Pipeline Co. LLC, two processing facilities in Wyoming, and Kinder Morgan’s 50 percent interest in the Rockies Express Pipeline to meet the FTC requirements. The FTC was attempting to strike a balance between potential cost reductions resulting from economies of scale and concentration of market power.

Did the price of natural gas decrease? Yes, rather significantly. In 2010, the wellhead price of natural gas was $4.48 per thousand cubic foot; in 2012 the price had fallen to just $2.66. Was the merger responsible for the large drop in price? The answer is uncertain. The larger contributor to the sharp drop in price was the overall increase in the supply of natural gas. More and more natural gas was able to be recovered by fracturing shale deposits, a process called fracking. Fracking, which is controversial for environmental reasons, enabled the recovery of known reserves of natural gas that previously were not economically feasible to tap. Kinder Morgan’s control of 80,000-plus miles of pipeline likely made moving the gas from wellheads to end users smoother and allowed for an even greater benefit from the increased supply.

The previous discussions on the theory of the firm identified three important lessons: First, that competition, by providing consumers with lower prices and a variety of innovative products, is a good thing; second, that large-scale production can dramatically lower average costs; and third, that markets in the real world are rarely perfectly competitive. As a consequence, government policymakers must determine how much to intervene to balance the potential benefits of large-scale production against the potential loss of competition that can occur when businesses grow in size, especially through mergers.

For example, in 2006, AT&T and BellSouth, two telecommunications companies, wished to merge into a single firm. In the year before the merger, AT&T was the 121 st largest company in the country when ranked by sales with $44 billion in revenues and 190,000 employees. BellSouth was the 314 th largest company in the country, with $21 billion in revenues and 63,000 employees.

The two companies argued that the merger would benefit consumers, who would be able to purchase better telecommunications services at a cheaper price because the newly created firm would be able to produce more efficiently by taking advantage of economies of scale and eliminating duplicate investments. However, a number of activist groups like the Consumer Federation of America and Public Knowledge expressed fears that the merger would reduce competition and lead to higher prices for consumers for decades to come. In December 2006, the federal government allowed the merger to proceed. By 2009, the new post-merger AT&T was the eighth largest company by revenues in the United States, and by that measure the largest telecommunications company in the world. Economists have spent – and will still spend – years trying to determine whether the merger of AT&T and BellSouth, as well as other smaller mergers of telecommunications companies at about this same time, helped consumers, hurt them, or did not make much difference.

This chapter discusses public policy issues about competition. How can economists and governments determine when mergers of large companies like AT&T and BellSouth should be allowed and when they should be blocked? The government also plays a role in policing anticompetitive behavior other than mergers, like prohibiting certain kinds of contracts that might restrict competition. In the case of natural monopoly, however, trying to preserve competition probably will not work very well, and so the government will often resort to a regulation of price and/or quantity of output. In recent decades, there has been a global trend toward less government intervention in the price and output decisions of businesses.

Self Check Questions

• What is a market structure?
• How many possible market structures are there? List, explain, and give an example of each type of market structure.
• Explain the term "laissez-faire". When was it first used? What did it mean then? What does it mean today?
• What is product differentiation? Give an example.
• What is collusion? How is it used?
• Define monopoly. Explain and give examples of the 3 possible types of monopolies that may exist.
• Explain and give examples of the 5 characteristics of perfect competition.
• How can the actions of one oligopoly affect the other oligopolies? Give 3 examples.
• List at least 5 stores where you shop. For each one, give at least 1 reason why you choose to spend your money there.

Live revision! Join us for our free exam revision livestreams Watch now →

Reference Library

Collections

• See what's new
• All Resources
• Student Resources
• Assessment Resources
• Teaching Resources
• CPD Courses
• Livestreams

Study notes, videos, interactive activities and more!

Economics news, insights and enrichment

Currated collections of free resources

Browse resources by topic

• All Economics Resources

Resource Selections

Currated lists of resources

Study Notes

4.1.5.1 Market structures (AQA Economics)

Last updated 20 Dec 2023

• Share on Facebook
• Share on Twitter
• Share by Email

Market structures play a crucial role in shaping economic outcomes, influencing prices, product varieties, and even innovation. This study guide delves into the spectrum of competition, ranging from the free-for-all of perfect competition to the singular authority of pure monopoly. By understanding these structures and the factors that shape them,

1. The Competition Spectrum: From Perfect Harmony to Absolute Power

Imagine a market like a bustling farmers' market, where countless vendors sell identical apples at similar prices. This perfect competition scenario represents an ideal of pure competition, characterized by:

• Many buyers and sellers: No single player has significant influence over price.
• Homogeneous products: All apples are essentially the same in quality and features.
• Free entry and exit: New entrants can easily join or existing firms can leave the market.
• Perfect information: Everyone has complete knowledge about prices, product quality, and market conditions.

Consequences:

• Price equals marginal cost: Firms operate at minimum efficient scale, leading to competitive pricing and consumer surplus.
• No economic profits in the long run: Excess profits attract new entrants, driving down prices to marginal cost.

Now, imagine the opposite extreme: a single company dominates the market for aspirin, with no close substitutes available. This pure monopoly scenario exemplifies the lack of competition, characterized by:

• Single seller: The monopolist controls the entire supply of a good or service.
• Unique product: No close substitutes exist, giving the monopolist significant market power.
• Barriers to entry: High costs or legal restrictions prevent new firms from entering the market.
• Imperfect information: The monopolist may have more information about the market than consumers, enabling them to set higher prices.
• Price exceeds marginal cost: The monopolist restricts output to maximize profits, leading to higher prices and deadweight loss (consumer losses not captured by producer gains).
• Economic profits in the long run: The lack of competition allows the monopolist to earn persistent profits.

2. Navigating the Shades of Competition: Between the Extremes

Most real-world markets fall somewhere between the extremes of perfect competition and pure monopoly. Key factors that determine the level of competition include:

• Number of firms: More firms generally indicate stronger competition, while fewer firms may lead to oligopolies (dominated by a few large firms) or monopolistic competition (many firms selling differentiated products).
• Product differentiation: Unique features or branding can create market power, allowing firms to charge higher prices. In contrast, homogeneous products lead to intense price competition.
• Barriers to entry: Factors like economies of scale, government regulations, or patents can prevent new firms from entering, reducing competition.
• Mobile phone market: Oligopolies like Apple and Samsung compete with differentiated products, creating some but not perfect competition.
• Cereal market: Many brands with various features exist, but economies of scale may favor larger producers,creating imperfect competition.
• Local taxi service: Limited licenses and high initial capital requirements create barriers to entry, potentially leading to monopolistic tendencies.

3. Beyond the Basics: Competition Matters, Even in the Real World

Understanding market structures and the level of competition within them is crucial for:

• Policymakers: Designing regulations to promote competition and prevent market failures caused by monopolies.
• Consumers: Making informed choices by understanding competitive pricing and product differentiation.
• Businesses: Strategizing effectively by analyzing competitor behavior and identifying market opportunities.

Conclusion:

Market structures are not static; they evolve due to technological advancements, regulatory changes, and consumer preferences. By understanding the forces shaping competition, we can navigate the complexities of markets and make informed economic decisions in a dynamic world.

• Perfect competition: A market structure with numerous buyers and sellers, homogeneous products, free entry and exit, and perfect information.
• Pure monopoly: A market structure with a single seller, a unique product, significant barriers to entry, and imperfect information.
• Oligopoly: A market structure with few large firms who compete or collude with each other.
• Monopolistic competition: A market structure with many firms selling differentiated products, leading to some but not perfect competition.
• Barriers to entry: Factors that hinder new firms from entering a market, such as economies of scale, government regulations, or patents.
• Economic profits: Profits earned by a firm above its normal costs in the long run.
• Deadweight loss: The welfare lost due to inefficient allocation of resources in a market, often caused by monopolies.
• Market structure

You might also like

What is market concentration, oligopoly - kinked demand curve, market structure, conduct and performance.

Teaching PowerPoints

Market Structures and their Characteristics (Quizlet Activity)

Quizzes & Activities

Barcelona introduces greater regulation on Airbnb

7th June 2018

A* Evaluation on Business Conduct and Efficiency

Topic Videos

Anti-competitive behaviour - CMA fines pharma firm over pricing of crucial thyroid drug

29th July 2021

Edexcel A-Level Economics (A) Theme 3 Knowledge Organiser Pack

Exam Support

Our subjects

• › Criminology
• › Economics
• › Geography
• › Health & Social Care
• › Psychology
• › Sociology
• › Teaching & learning resources
• › Student revision workshops
• › Online student courses
• › CPD for teachers
• › Livestreams
• › Teaching jobs

Boston House, 214 High Street, Boston Spa, West Yorkshire, LS23 6AD Tel: 01937 848885

• › Contact us
• › Terms of use
• › Privacy & cookies

© 2002-2024 Tutor2u Limited. Company Reg no: 04489574. VAT reg no 816865400.

ECON101: Principles of Microeconomics (2021.A.01)

Econ101 study guide, unit 6: market structure: competitive and non-competitive markets, 6a. identify the characteristic differences between various market structures, namely, perfectly competitive markets, non-competitive markets, and imperfectly competitive markets, and discuss differences in their operations.

• Define  differentiated , and  homogeneous  products.
• How many companies can exist in each of the four types of markets?
• Do additional companies experience any barriers to entry?
• Are products differentiated among different sellers?
• Do companies have market power, which means they are able to control supply and prices?
• Can companies sustain the amount of profit they receive for the long run?

Let's review different market structures and their characteristics. Monopolistic competition is the most common market structure, characterized by brand name and slightly differentiated products with many substitutes. The market structures perfect competition and monopoly offer theoretical extremes – they rarely exist in their purest forms, but we use these concepts as benchmarks to compare more common structures, such as monopolistic competition and oligopoly.

This table summarizes important distinctions among the four market structures. Note that mixed or hybrid structures, which encompass a mixture of characteristics, exist in addition to these four structures. For example, a market leader with a fringe of small competitors is a common market structure that combines monopoly and monopolistic competition.

Differentiated products means that each product is slightly or significantly different from the other and appeals to different customer wants or needs (think about different types of shoes, cars, or computer equipment). Undifferentiated or homogeneous means that all of the products are the same (think about a natural resource, such as oil, milk or sugar cane).

• Perfect Competition
• Define perfect competition .
• What sequence of events indicates a favorable market change that will cause existing companies to earn economic profit ?
• What sequence of events indicates an unfavorable market change that will cause existing companies to suffer an economic loss ?
• Why is it difficult for companies to sustain short-run profits or losses, causing them to make zero economic profits in the long run?

A perfectly competitive market assumes a large number of companies sell identical products and additional companies can enter and exit the industry freely. We call these companies "price takers" because they have no market power whatsoever, such as the ability to control prices.

Some students fail to recognize that zero economic profit is a reasonable and worthwhile outcome for a business. Remember the calculation for economic profit: accounting profit minus opportunity costs.

For example, an owner runs a business that earns $60,000 a year in accounting profit. However, the economic profit for the business is zero because the owner quit their corporate job where their salary was the same amount ($60,000). Accounting profit ($60,000) minus the opportunity cost of the owner's previous corporate job ($60,000) equals zero.

A company that makes zero economic profit is paying its bills and doing the best it can, without a better alternative use of its resources. In this situation, the company will remain in business.

Review these graphs from Competitive Markets for Goods and Services , which illustrate the dynamics that result from short-run economic profit or loss outcomes.

Eliminating Economic Profits in the Long Run

If companies in a particular industry are making an economic profit, other companies will join them in the long run. In Panel (b), a single company's profit is shown by the shaded area. Entry continues until companies in the industry are operating at the lowest point on their respective average total cost curves, and economic profits fall to zero.

Eliminating Economic Losses in the Long Run

Panel (b) shows that at the initial price P1, companies in the industry cannot cover average total cost (marginal revenue, MR1, is below average total cost, ATC). This induces some companies to leave the industry, shifting the supply curve in Panel (a) to supply, S2, reducing industry output to quantity, Q2, and raising price to P2. At this price (MR2), companies earn zero economic profit, and companies stop leaving the industry.

Panel (b) shows that when the company increases output from q1 to q2; total output in the market falls in Panel (a) because there are fewer companies. Notice that in Panel (a) quantity is designated by uppercase Q, while in Panel (b) quantity is designated by lowercase q. Note that in these graphs, (Q) is the quantity supplied in the market and (q) is the quantity supplied by one typical company.

Review the characteristics of a perfectly competitive market structure and company behavior in response to changes in market conditions in:

• Competitive Markets for Goods and Services
• Introduction to Perfect Competition  
• Define  monopoly .
• Define the  profit maximizing rule .
• Is this monopoly company making a  positive  economic profit?
• Why are firms operating under monopolies  less efficient  than firms operating under perfect competition?
• What are the effects of monopoly on consumer and producer surplus?
• How does public policy attempt to resolve issues associated with monopoly?
• Define  price discrimination .
• Define a  natural monopoly .
• Name some real-world examples of price discrimination and a natural monopoly.

A monopoly is at the opposite end of the market structure spectrum from perfect competition. A monopoly includes just one producer who is a "price maker", which has full control over the market price and quantity. There are no competitors and significant, strong barriers that restrict additional companies from entering this market. A monopoly can remain profitable during the long run since its position is unchallenged. Can you think of an example of a company that enjoys a monopoly?

We can determine a monopoly firm's profit-maximizing price and output by following three steps:

• Determine consumer demand, marginal revenue, and marginal cost curves.
• Choose the output level where the marginal revenue and marginal cost curves intersect.
• Determine the price from the consumer demand curve for the quantity found in step 2.

Once we have determined the monopoly company's price and output, we can determine its economic profit by calculating the area shaded in green in the below graph.

Computing Monopoly Profit

Read up from Qm to the demand curve to find the price Pm where the monopoly company can sell Qm units per period. Point E on the demand curve is the profit-maximizing price and output.

The average total cost (ATC) at an output of Qm units is ATCm. Consequently, the company's profit per unit is Pm minus ATCm. Determine the total profit by multiplying the company's output, Qm, by profit per unit. Total profit equals Qm(Pm minus ATCm): the area of the shaded rectangle.

A monopoly maximizes profit by producing an output Qm at point G, where the marginal revenue and marginal cost curves intersect. It sells this output at price Pm.

An important distinction between a monopoly and perfect competition is that the monopoly meets the demand of the entire industry, is free to charge customers more for what it produces, and is able to sell less product than it would if it were a perfectly competitive company.

Review the monopoly structure in:

• Introduction to a Monopoly
• Monopoly Basics
• Review of Revenue and Cost Graphs for a Monopoly
• Monopolist Optimizing Price (Part 1): Total Revenue
• Monopolist Optimizing Price (Part 2): Marginal Revenue
• Monopolist Optimizing Price (Part 3): Deadweight Loss
• Price Discrimination
• Marginal Costing Quiz and Monopoly Quantitative Exercise
• Monopolistic Competition
• What is the optimization rule for monopolistically competitive firms?
• How do monopolistically competitive firms compare with perfectly competitive firms?
• How do monopolistically competitive firms compare with monopoly firms?
• Why and how is the economic profit of monopolistically competitive firms reduced to $0 in the long-run?

Monopolistic competition lies in the middle of the market structure spectrum: between perfect competition and a monopoly. In this type of structure, we see many producers, as in perfect competition, and fierce competition drives long-run economic profits to zero. However, companies in monopolistic competition produce differentiated products and have the ability to exert some market power. They have some control over prices, and limited barriers protect them from other companies that want to enter their market.

It is easy to point to examples of companies operating in monopolistically competitive market structure since they use brand names to differentiate their product, and each one typically has many close, but not identical, substitutes.

As with a monopoly, companies in monopolistic competition face the entire market demand for their product. Their demand curve slopes downward since consumers will buy fewer products as their price increases. The graphical analysis for a monopolistically competitive company resembles that of a monopoly company.

Short-Run Equilibrium in Monopolistic Competition

As you review this chart, examine the intersection of the marginal revenue curve MR1 and the marginal cost curve MC, to see that the profit-maximizing quantity is 2,150 units per week. Reading up to the average total cost curve ATC, we see the cost per unit equals $9.20. Price, given on the demand curve D1, is $10.40, so the profit per unit is $1.20. Total profit per week equals $1.20 times 2,150, or $2,580; it is shown by the shaded rectangle.

When companies in monopolistic competition make positive economic profits in the short-run, new companies enter the market to produce similar products. Eventually, profits decrease due to this fierce competition, and profits are eliminated in the long run.

Monopolistic Competition in the Long Run

As you review this chart, the existence of economic profits in a monopolistically competitive industry will induce entry in the long run. As new firms enter, the demand curve D1 and marginal revenue curve MR1 facing a typical firm will shift to the left, to D2 and MR2. Eventually, this shift produces a profit-maximizing solution at zero economic profit, where D2 is tangent to the average total cost curve ATC (point A). The long-run equilibrium solution here is an output of 2,000 units per week at a price of $10 per unit.

Review monopolistic competition in:

• Monopolistic Competition: Competition among Many
• Oligopolies and Monopolistic Competition
• Monopolistic Competition and Economic Profit
• Define  oligopoly .
• Define  cartel  and  collusion .
• Name some real-world examples of companies that fall under oligopoly structure.
• How was OPEC able to inflate prices for oil and gas to enrich oil-producing countries in the Middle East?
• How is  game theory  used to study strategic behavior in oligopolies?
• Define dominant strategy.
• Define what a  Nash Equilibrium  is and how it is determined.
• What are some examples of the use of game theory to study oligopoly behavior?

An oligopoly lies between a monopoly and perfect competition on the market spectrum but leans more toward a monopoly since a group of companies work together to create monopoly-like conditions they can all profit from. By colluding, or cooperating among each other (either secretly or openly via a formal cartel), oligopoly companies "artificially" prop up prices to ensure they all maintain collective profitability. In an oligopoly, a few companies produce a differentiated product, enjoy significant market power, control prices, and are able to sustain positive economic profits in the long run.

Oligopoly companies have a tremendous impact on each other's operations: while they all benefit when they can work together, they are often fraught with discord and mistrust. They typically engage in strategic behavior, which involves constant vigilance, as they counteract any actions other cartel members might take to promote their market position.

Since they do not enjoy a complete monopoly, cartel members need to be sure to keep up with any product improvements other members make, match their advertising spending, and make sure their product is similarly placed among their customers, so no one member of the group obtains a competitive advantage above the others.

Additionally, one rogue member of the cartel may try to undercut the lowest price the group had agreed to charge, to attract all of the customers, because they are greedy or need the extra money. Another cartel member may try to secretly sell more product than the group had agreed to supply at the higher price. According to the laws of supply and demand, if one cartel member floods the market with their product, the price for the good will fall, and everyone in the cartel will suffer.

Oligopoly companies often work together to avoid public officials who aim to curtail the inflated prices on behalf of their political constituents and consumers. However, when cartel members can no longer agree to work together to limit their supply to inflate prices, their disputes run the risk of triggering a price war that will benefit public consumers, but damage the mutually-inflated profit margin the cartel members previously enjoyed.

Monopoly through Collusion

Two identical firms have the same horizontal marginal cost curve MC. Their demand curves Dfirm and marginal revenue curves MRfirm are also identical. The combined demand curve is Dcombined; the combined marginal revenue curve is MRcombined. The profits of the two firms are maximized if each produces 1/2 Qm at point A. Industry output at point B is thus Qm and the price is Pm. At point C, the efficient solution output would be Qc, and the price would equal MC.

The Prisoner's Dilemma offers an interesting framework for analyzing strategic behavior among oligopoly companies. Companies engage in strategic behavior as they consider the actions of their competitors when making decisions, and intend to preempt or change final outcomes. For example, a company may want to outspend the advertising budget of its opponent when it decides how much money it should allocate to advertising next year. Another company may decide to preemptively invest in a large amount of capital to communicate a credible threat to its opponents of its intention to capture market share.

Figure 11.4 shows the decisions and outcomes available to players: two prisoners weigh "confessing" against "not confessing" to a crime. The four cells represent each possible outcome of the Prisoner's Game. Since the choice of the other prisoner will affect the final outcome on their prison sentence, what do the prisoners choose? Competitors often choose an option that is not mutually beneficial as they try to outplay each other.

Payoff Matrix for the Prisoner's Dilemma

Review the strategies of each player, note any dominant strategy, and the final outcome of the game, the Nash Equilibrium, if it exists. The Nash Equilibrium exists where each player's choice is the best response to what the other player has chosen and none of the players has an incentive to change their choice in equilibrium. Why do both players "confess" when "not confessing" is clearly a better outcome for them both?

Review the oligopoly market structure, game theory, the Prisoner's Dilemma, and the Nash Equilibrium in the following resources.

• Oligopoly: Competition among Few
• Oligopolies, Duopolies, Collusion, and Cartels
• Game Theory of Cheating Firms
• More on Nash Equilibrium
• Why Parties to Cartels Cheat
• Prisoner's Dilemma and Nash Equilibrium

6b. Compare and contrast as well as discuss the three main kinds of economic systems

• Define, compare, and contrast the three main kinds of economic systems: traditional economy , command economy , market economy .

Review this material in How Economies Can Be Organized: An Overview of Economic Systems .

Unit 6 Vocabulary

• Command economy
• Competitive advantage
• Differentiated
• Dominant strategy
• Economic loss
• Economic profit
• Game theory
• Homogeneous
• Marginal profit
• Marginal revenue
• Market economy
• Monopolistic competition
• Nash Equilibrium
• Natural monopoly
• Perfect competition
• Price discrimination
• Prisoners' dilemma
• Profit maximizing rule
• Strategic choice
• Traditional economy

Comparing Market Structures

Working in predetermined teams of 4-5 students, teams will examine and identify the market structure for cell phone operating systems. After examining the current market structure, teams will be asked to analyze the impact of a powerful entrant into the industry.

Expand for more detail

Activity Classification and Connections to Related Resources Collapse

Grade level, learning goals, context for use.

This exercise should be completed after the students have learned about perfect competition, monopoly, monopolistic competition and oligopoly. Students complete the exercise in teams of 4-5 students. The exercise generally takes 15-20 minutes to complete in teams and 10-15 minutes to review as a whole class exercise.

Working in predetermined teams of 4-5 students, teams will analyze the market structure for cell phone operating systems to identify which of the four market structures is exhibited: perfect competition, monopoly, monopolistic competition, and oligopoly. Then teams will analyze the impact of an entrant into the industry.

Expected Student Learning Outcomes

Students will be able to identify the characteristics of each of the market structures: perfect competition, monopoly, monopolistic competition and oligopoly. Students will be able to compare and contrast the market structures.

Students will be able to analyze the impact of an entrant into an oligopolistic industry.

Information Given to Students

Before Class to Prepare for the AE

Students are asked to complete the Comparing Market Structures at-home assignment. The assignment asks students to read two online articles. The first details the trends in global market share in the smartphone operating systems market since 2009. The second article discusses Microsoft's difficulties in establishing a foothold in the industry since the early 2000s. Both will provide background information for students so that they will have a meaningful in-class discussion.

Comparing Market Structures AE

Consider the market for cell phone operating systems below:

https://www.statista.com/statistics/266136/global-market-share-held-by-smartphone-operating-systems/

Suppose that you are the President of the Board of Directors for Research in Motion (RIM: the operating system of the former Blackberry cell phone). What would you recommend that Microsoft do?

1. Advertise to increase its market share.

2. Leave the industry.

3. Tie the function of the Microsoft smartphone more closely to the operation of the Windows computer.

4. Conduct R & D to develop new, highly useful features that are unique to Microsoft phones.

Comparing Market Structures at-home Assignment (Microsoft Word 2007 (.docx) 13kB Feb18 18)

Student Handout for Comparing Market Structures (Microsoft Word 2007 (.docx) 118kB Jan24 18)

Teams will report out their answer collectively, on a submission paper or on the board, depending upon how visual you want the answers to be. I also collect the student handout from each student so that I can provide them with "credit" or "half-credit" or "no credit" for their participation in the activity. I explain to students that I expect to "see" their notes and graphs that detail how they reached the answer. I also circulate the room during the entire team activity to redirect student discussions and clarify the activity or the course material. Alternatively, you can collect one sheet per team and provide "credit" or "participation" points for team activity.

Teaching Notes

Students are placed into teams of 4-5 students (typically at the start of the semester). Before class, to prepare students for the exercise, ask students to complete the Comparing Market Structure at-home assignment and bring it to the next class meeting. At the beginning of the next class meeting, they are provided with the attached handout or the market share data can be projected for the entire class to see. As students enter the classroom, I record the completion of the at-home assignment. This is a credit/no-credit activity and can be used toward homework or participation points.

Students must then choose a recorder (this is done on a rotating basis so that every student in a team will be the reporter several times during a semester) who will report the findings and rationale for their team during the entire class discussion. Give students 15 minutes to discuss the question. They may use the textbook and online sources, if allowed. After the 15 minutes, ask each of the reporters to provide their answer and rationale to the question. Create a class list/tally on the board.

Students complete the Comparing Market Structures exercise in teams during class. I encourage students to use their own personal knowledge of cell phone operating systems since this allows them some expertise and self-efficacy. During the discussion, I circulate the classroom to answer questions and redirect or increase engagement in the discussion. The handout can be collected for participation points or credit at the end of the class session. I find that when the exercise is collected at the end of the class meeting, students generally take more detailed notes and expect a correct answer to record. However, when the exercise is not collected at the end of the class meeting, students take fewer notes but engage in the discussion in class. In this case, I ask students to take 5-minutes at the end and summarize their discussion on the handout for their own records.

Since all of Microsoft's choices above have merit, it is important that you ask students to provide information from their readings, textbook and online sources if allowed to use those during class. If there is a consensus around one of the choices (such as "Leave the industry" because the article claims that is what Microsoft ought to do) then play devil's advocate and ask the teams to rank the choices from best to worst. This will allow you to discuss each of the options and have teams provide their rationale for their rankings.

See more Application Exercise Library »

An official website of the United States government.

Here’s how you know

The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Occupational Safety and Health Administration

• 中文（简体） (Chinese-Simplified)
• 繁體中文 (Chinese-Traditional)
• Kreyòl ayisyen (Haitian Creole)
• 한국어 (Korean)
• Español (Spanish)
• Filipino/Tagalog
• Tiếng Việt (Vietnamese)
• Federal Registers
• Hazard Communication Standard; Final Rule
• Publication Date: 05/20/2024
• Publication Type: Final Rule
• Fed Register #: 89:44144-44461
• Standard Number: 1910.1200
• Title: Hazard Communication Standard; Final Rule