9.2How a Profit-Maximizing Monopoly Chooses Output and Price
Barrier to Government Role? Example Government often responds with regulation (or ownership) Water and electric companies Control of a physical resource No DeBeers for diamonds Yes Post office, past regulation of airlines and trucking , , and Yes, through protection of New drugs or software Intimidating potential competitors Somewhat ; well-known names TABLE 9.1Barriers to
9.2 How a Profit-Maximizing Monopoly Chooses Output and Price
LEARNING OBJECTIVES By the end of this section, you will be able to:
- Explain the perceived for a perfect competitor and a
- Analyze a for a and determine the output that maximizes profit and
- Calculate and
- Explain as it pertains to the efficiency of a
Consider a , comfortably surrounded by so that it need not fear competition from other producers. How will this choose its profit-maximizing quantity of output, and what will it charge? Profits for the monopolist, like any , will be equal to total revenues minus total costs. We can analyze the pattern of costs for the within the same framework as the costs of a perfectly competitive —that is, by using , , , , 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. (The Clear It Up feature discusses how hard it is sometimes to define “market” in a monopoly situation.)
Demand Curves Perceived by a Perfectly Competitive Firm and by a Monopoly
A perfectly competitive acts as a , so we calculate total taking the given and multiplying it by the quantity of output that the chooses. The as it is perceived by a perfectly competitive appears in (a). The flat perceived means that, from the viewpoint of the perfectly competitive , it could sell either a relatively low quantity like Ql or a relatively high quantity like Qh at the P.
FIGURE 9.3The Perceived for a Perfect Competitor and a Monopolist (a) A perfectly competitive perceives the that it faces to be flat. The flat shape means that the can sell either a low quantity (Ql) or a high quantity (Qh) at exactly the same (P). (b) A monopolist perceives the that it faces to be the same as the , 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 (PI). Conversely, if the monopolist chooses a low level of output (Ql), it can then charge a higher (Ph). The challenge for the monopolist is to choose the combination of and quantity that maximizes profits. CLEAR IT UP What defines the ? A monopoly is a firm that sells all or nearly all of the goods and services in a given market. However, 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 it dismissed the case against DuPont. 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 14% in 2014. 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 we can consider the firm a monopoly producer in a single market. However, 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. While a monopolist can charge any price for its product, nonetheless the demand for the firm’s product constrains the price. 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. illustrates this situation. The monopolist can either choose a point like R with a low (Pl) and high quantity (Qh), or a point like S with a high (Ph) and a low quantity (Ql), or some intermediate point. Setting the too high will result in a low quantity sold, and will not bring in much . Conversely, setting the too low may result in a high quantity sold, but because of the low , it will not bring in much either. The challenge for the monopolist is to strike a profit-maximizing balance between the it charges and the quantity that it sells. However, why isn’t the perfectly competitive ’s also the ? See the following Clear It Up feature for the answer to this question. CLEAR IT UP 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 demand for its product in a market where the monopoly is the only producer.
Total Cost and Total Revenue for a Monopolist
We can illustrate profits for a monopolist with a graph of total revenues and total costs, with the example of the hypothetical HealthPill in . The curve has its typical shape that we learned about in , Costs and Industry , and that we used in ; that is, total costs rise and the curve grows steeper as output increases, as the final column of shows.
FIGURE 9.4Total and for the HealthPill Total for the called HealthPill first rises, then falls. Low levels of output bring in relatively little total , because the quantity is low. High levels of output bring in relatively less , because the high quantity pushes down the . The curve is upward-sloping. Profits will be highest at the quantity of output where total is most above total cost. The profit-maximizing level of output is not the same as the revenue-maximizing level of output, which should make sense, because profits take costs into account and revenues do not. Quantity Price Total Revenue Total Cost Q P TR TC 1 1,200 1,200 500 2 1,100 2,200 750 3 1,000 3,000 1,000 4 900 3,600 1,250 5 800 4,000 1,650 6 700 4,200 2,500 7 600 4,200 4,000 8 500 4,000 6,400 TABLE 9.2Total Costs and Total Revenues of HealthPill Total revenue, though, is different. Since a monopolist faces a downward sloping demand curve, the only way it can sell more output is by reducing its price. Selling more output raises revenue, but lowering price reduces it. Thus, the shape of total revenue isn’t clear. Let’s explore this using the data in , which shows quantities along the and the at each , and then calculates total by multiplying times quantity at each level of output. (In this example, we give the output as 1, 2, 3, 4, and so on, for the sake of simplicity. If you prefer a dash of greater realism, you can imagine that the pharmaceutical company measures these output levels and the corresponding prices per 1,000 or 10,000 pills.) As the figure illustrates, total for a monopolist has the shape of a hill, first rising, next flattening out, and then falling. In this example, total is highest at a quantity of 6 or 7. However, the monopolist is not seeking to maximize , but instead to earn the highest possible profit. In the HealthPill example in , the highest profit will occur at the quantity where total is the farthest above . This looks to be somewhere in the middle of the graph, but where exactly? It is easier to see the profit maximizing level of output by using the marginal approach, to which we turn next.
Marginal Revenue and Marginal Cost for a Monopolist
In the real world, a monopolist often does not have enough information to analyze its entire total revenues or total costs curves. After all, the does not know exactly what would happen if it were to alter dramatically. However, a monopolist often has fairly reliable information about how changing output by small or moderate amounts will affect its marginal revenues and marginal costs, because it has had experience with such changes over time and because modest changes are easier to extrapolate from current experience. A monopolist can use information on and to seek out the profit-maximizing combination of quantity and . expands using the figures on total costs and total revenues from the HealthPill example to calculate and . This faces typical upward-sloping and downward-sloping curves, as shows. Notice that is zero at a quantity of 7, and turns negative at quantities higher than 7. It may seem counterintuitive that could ever be zero or negative: after all, doesn't an increase in quantity sold not always mean more ? For a perfect competitor, each additional unit sold brought a positive , because was equal to the given . However, a monopolist can sell a larger quantity and see a decline in total . When a monopolist increases sales by one unit, it gains some from selling that extra unit, but also loses some because it must now sell every other unit at a lower . As the quantity sold becomes higher, at some point the drop in is proportionally more than the increase in greater quantity of sales, causing a situation where more sales bring in less revenue. In other words, marginal revenue is negative.
FIGURE 9.5Marginal and for the HealthPill For a like HealthPill, decreases as it sells additional units of output. The curve is upward-sloping. The profit-maximizing choice for the will be to produce at the quantity where is equal to : that is, MR = MC. If the produces a lower quantity, then MR > MC at those levels of output, and the can make higher profits by expanding output. If the produces at a greater quantity, then MC > MR, and the firm can make higher profits by reducing its quantity of output. Quantity Total Revenue Marginal Revenue Total Cost Marginal Cost Q TR MR TC MC 1 1,200 1,200 500 500 2 2,200 1,000 775 275 3 3,000 800 1,000 225 4 3,600 600 1,250 250 5 4,000 400 1,650 400 6 4,200 200 2,500 850 7 4,200 0 4,000 1,500 8 4,000 –200 6,400 2,400 TABLE 9.3Costs and Revenues of HealthPill A monopolist can determine its profit-maximizing price and quantity by analyzing the marginal revenue and marginal costs of producing an extra unit. If the marginal revenue exceeds the marginal cost, then the firm should produce the extra unit. For example, at an output of 4 in , is 600 and is 250, so producing this unit will clearly add to overall profits. At an output of 5, is 400 and is 400, so producing this unit still means overall profits are unchanged. However, expanding output from 5 to 6 would involve a of 200 and a of 850, so that sixth unit would actually reduce profits. Thus, the can tell from the and that of the choices in the table, the profit-maximizing level of output is 5. The could seek out the profit-maximizing level of output by increasing quantity by a small amount, calculating and , and then either increasing output as long as marginal revenue exceeds marginal cost or reducing output if marginal cost exceeds marginal revenue. This process works without any need to calculate total revenue and total cost. Thus, a profit-maximizing monopoly should follow the rule of producing up to the quantity where marginal revenue is equal to marginal cost—that is, MR = MC. This quantity is easy to identify graphically, where MR and MC intersect. WORK IT OUT Maximizing Profits If you find it counterintuitive that producing where marginal revenue equals marginal cost will maximize profits, working through the numbers will help. Step 1. Remember, we define marginal cost as the change in total cost from producing a small amount of additional output. Step 2. Note that in , as output increases from 1 to 2 units, increases from $500 to $775. As a result, the of the second unit will be: Step 3. Remember that, similarly, is the change in total from selling a small amount of additional output. Step 4. Note that in , as output increases from 1 to 2 units, total increases from $1200 to $2200. As a result, the of the second unit will be: Quantity Total Profit Q MR MC MP P 1 1,200 500 700 700 2 1,000 275 725 1,425 3 800 225 575 2,000 4 600 250 350 2,350 TABLE 9.4 , , Marginal and Total Profit Quantity Total Profit Q MR MC MP P 5 400 400 0 2,350 6 200 850 −650 1,700 7 0 1,500 −1,500 200 8 −200 2,400 −2,600 −2,400 TABLE 9.4 , , Marginal and Total Profit repeats the and data from , and adds two more columns: is the profitability of each additional unit sold. We define it as minus . Finally, total profit is the sum of marginal profits. As long as is positive, producing more output will increase total profits. When turns negative, producing more output will decrease total profits. Total profit is maximized where equals . In this example, maximum profit occurs at 5 units of output. A perfectly competitive will also find its profit-maximizing level of output where MR = MC. The key difference with a perfectly competitive is that in the case of , is equal to (MR = P), while for a monopolist, marginal revenue is not equal to the price, because changes in quantity of output affect the price.
Illustrating Monopoly Profits
It is straightforward to calculate profits of given numbers for total and . However, the size of profits can also be illustrated graphically with , which takes the and curves from the previous exhibit and adds an average cost curve and the monopolist’s perceived . shows the data for these curves. Quantity Average Cost Q P MR MC AC 1 1,200 1,200 500 500 2 1,100 1,000 275 388 3 1,000 800 225 333 4 900 600 250 313 5 800 400 400 330 6 700 200 850 417 7 600 0 1,500 571 8 500 –200 2,400 800 TABLE 9.5
FIGURE 9.6Illustrating Profits at the HealthPill MonopolyThis figure begins with the same and curves from the HealthPill from . It then adds an average cost curve and the that the monopolist faces. The HealthPill first chooses the quantity where MR = MC. In this example, the quantity is 5. The monopolist then decides what to charge by looking at the it faces. The large box, with quantity on the horizontal axis and (which shows the ) on the vertical axis, shows total for the . The lighter-shaded box, which is quantity on the horizontal axis and average cost of on the vertical axis shows the 's total costs. The large total box minus the smaller box leaves the darkly shaded box that shows total profits. Since the price charged is above average cost, the firm is earning positive profits. illustrates the three-step process where a monopolist: selects the profit-maximizing quantity to produce; decides what to charge; determines total , , and profit. Step 1: The Monopolist Determines Its Profit-Maximizing Level of Output The can use the points on the D to calculate total , and then, based on total , calculate its curve. The profit-maximizing quantity will occur where MR = MC—or at the last possible point before marginal costs start exceeding . On , MR = MC occurs at an output of 5. Step 2: The Monopolist Decides What to Charge The monopolist will charge what the is willing to pay. A dotted line drawn straight up from the profit- maximizing quantity to the shows the profit-maximizing which, in , is $800. This is above the average cost curve, which shows that the is earning profits. Step 3: Calculate Total , , and Profit Total is the overall shaded box, where the width of the box is the quantity sold and the height is the . In , this is 5 x $800 = $4000. In , the bottom part of the shaded box, which is shaded more lightly, shows total costs; that is, quantity on the horizontal axis multiplied by average cost on the vertical axis or 5 x $330 = $1650. The larger box of total revenues minus the smaller box of total costs will equal profits, which the darkly shaded box shows. Using the numbers gives $4000 - $1650 = $2350. In a perfectly competitive , the forces of would erode this profit in the . However, a monopolist is protected by . In fact, one obvious sign of a possible is when a earns profits year after year, while doing more or less the same thing, without ever seeing increased competition eroding those profits.
FIGURE 9.7How a Profit-Maximizing Decides PriceIn Step 1, the chooses the profit- maximizing level of output Q1, by choosing the quantity where MR = MC. In Step 2, the decides how much to charge for output level Q1 by drawing a line straight up from Q1 to point R on its perceived . Thus, the will charge a (P1). In Step 3, the identifies its profit. Total will be Q1 multiplied by P1. will be Q1 multiplied by the average cost of producing Q1, which point S shows on the average cost curve to be P2. Profits will be the total rectangle minus the rectangle, which the shaded zone in the figure shows. CLEAR IT UP Why is a monopolist’s always less than the price? The marginal revenue curve for a monopolist always lies beneath the market demand curve. To understand why, think about increasing the quantity along the demand curve by one unit, so that you take one step down the demand curve to a slightly higher quantity but a slightly lower price. A demand curve is not sequential: It is not that first we sell Q1 at a higher price, and then we sell Q2 at a lower price. Rather, a demand curve is conditional: If we charge the higher price, we would sell Q1. If, instead, we charge a lower price (on all the units that we sell), we would sell Q2. When we think about increasing the quantity sold by one unit, marginal revenue is affected in two ways. First, we sell one additional unit at the new market price. Second, all the previous units, which we sold at the higher price, now sell for less. Because of the lower price on all units sold, the marginal revenue of selling a unit is less than the price of that unit—and the marginal revenue curve is below the demand curve. Tip: For a straight-line demand curve, MR and demand have the same vertical intercept. As output increases, marginal revenue decreases twice as fast as demand, so that the horizontal intercept of MR is halfway to the horizontal intercept of demand. You can see this in the .
FIGURE 9.8The Monopolist’s Curve versus Because the is conditional, the curve for a monopolist lies beneath the .
The Inefficiency of Monopoly
Most people criticize monopolies because they charge too high a , but what economists object to is that monopolies do not supply enough output to be allocatively efficient. To understand why a is inefficient, it is useful to compare it with the benchmark of . is an economic concept regarding efficiency at the social or societal level. 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 . The rule of profit maximization in a world of was for each to produce the quantity of output where P = MC, where the (P) is a measure of how much buyers value the good and the (MC) is a measure of what marginal units cost society to produce. Following this rule assures . If P > MC, then the marginal benefit to society (as measured by P) is greater than the to society of producing additional units, and a greater quantity should be produced. However, in the case of monopoly, price is always greater than marginal cost at the profit- maximizing level of output, as you can see by looking back at . Thus, consumers do not benefit from a because it will sell a lower quantity in the , at a higher , than would have been the case in a perfectly competitive . The problem of inefficiency for monopolies often runs even deeper than these issues, and 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 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 is in place, a 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 in 1972, wrote in 1935: “The best of all 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 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. However, in 1982, government litigation split up AT&T into a number of local phone companies, a long-distance phone company, and a phone equipment manufacturer. An explosion of followed. Services like call waiting, caller ID, three-way calling, voice mail through the phone company, mobile phones, and wireless connections to the internet all became available. Companies offered a wide range of payment plans, as well. It was no longer true that all phones were black. Instead, phones came in a wide variety of shapes and colors. The end of the telephone brought lower prices, a greater quantity of services, and also a wave of innovation aimed at attracting and pleasing customers. BRING IT HOME The Rest is History In the opening case, we presented the East India Company and the Confederate States as a monopoly or near monopoly provider of a good. Nearly every American schoolchild knows the result of the “unwelcome visit” the “Mohawks” bestowed upon Boston Harbor’s tea-bearing ships—the Boston Tea Party. Regarding the cotton industry, we also know Great Britain remained neutral during the Civil War, taking neither side during the conflict. Did the monopoly nature of these business have unintended and historical consequences? Might the American Revolution have been deterred, if the East India Company had sailed the tea-bearing ships back to England? Might the southern states have made different decisions had they not been so confident “King Cotton” would force diplomatic recognition of the Confederate States of America? Of course, it is not possible to definitively answer these questions. We cannot roll back the clock and try a different scenario. We can, however, consider the monopoly nature of these businesses and the roles they played and hypothesize about what might have occurred under different circumstances. Perhaps if there had been legal free tea trade, the colonists would have seen things differently. There was smuggled Dutch tea in the colonial market. If the colonists had been able to freely purchase Dutch tea, they would have paid lower prices and avoided the tax. What about the cotton monopoly? With one in five jobs in Great Britain depending on Southern cotton and the Confederate States as nearly the sole provider of that cotton, why did Great Britain remain neutral during the Civil War? At the beginning of the war, Britain simply drew down massive stores of cotton. These stockpiles lasted until near the end of 1862. Why did Britain not recognize the Confederacy at that point? Two reasons: The Emancipation Proclamation and new sources of cotton. Having outlawed slavery throughout the United Kingdom in 1833, it was politically impossible for Great Britain, empty cotton warehouses or not, to recognize, diplomatically, the Confederate States. In addition, during the two years it took to draw down the stockpiles, Britain expanded cotton imports from India, Egypt, and Brazil. Monopoly sellers often see no threats to their superior marketplace position. In these examples did the power of the monopoly hide other possibilities from the decision makers? Perhaps. As a result of their actions, this is how history unfolded.
Key Terms
the legal, technological, or forces that may discourage or prevent potential competitors from entering a a form of legal protection to prevent copying, for commercial purposes, original works of authorship, including books and music removing government controls over setting prices and quantities in certain industries the body of law including patents, trademarks, copyrights, and law that protect the right of inventors to produce and sell their inventions legal prohibitions against competition, such as regulated monopolies and protection profit of one more unit of output, computed as minus monopoly a situation in which one firm produces all of the output in a market natural monopoly economic conditions in the industry, for example, economies of scale or control of a critical resource, that limit effective competition patent a government rule that gives the inventor the exclusive legal right to make, use, or sell the invention for a limited time predatory pricing when an existing firm uses sharp but temporary price cuts to discourage new competition trade secrets methods of production kept secret by the producing firm trademark an identifying symbol or name for a particular good and can only be used by the firm that registered that trademark
Key Concepts and Summary
9.1 How Monopolies Form: Barriers to Entry
prevent or discourage competitors from entering the . These barriers include: that lead to ; control of a physical resource; legal restrictions on competition; , and protection; and practices to intimidate the competition like . refers to legally guaranteed ownership of an idea, rather than a physical item. The laws that protect include patents, copyrights, trademarks, and . A arises when economies of scale persist over a large enough range of output that if one firm supplies the entire market, no other firm can enter without facing a cost disadvantage.
9.2 How a Profit-Maximizing Monopoly Chooses Output and Price
A monopolist is not a , because when it decides what quantity to produce, it also determines the . For a monopolist, total is relatively low at low quantities of output, because it is not selling much. Total is also relatively low at very high quantities of output, because a very high quantity will sell only at a low . Thus, total for a monopolist will start low, rise, and then decline. The for a monopolist from selling additional units will decline. Each additional unit a monopolist sells will push down the overall , and as it sells more units, this lower applies to increasingly more units. The monopolist will select the profit-maximizing level of output where MR = MC, and then charge the 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.
Text from Principles of Microeconomics 3e, OpenStax, licensed CC BY-NC-SA 4.0. Access for free at openstax.org.
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