垄断 垄断 Monopoly Monopoly 竞争企业是价格接受者,而垄 断企业是价格制定者。 第15章 While a competitive firm is a Chapter 15 price taker, a me I price ma 垄断 Monopoly 为什么会产生垄断 Why Monopolies Arise 一个企业被认为是垄断,如果 A firm is considered a monopoly 产生垄断的根本原因是进入障碍 它是其产品的唯一的卖者。 The fundamental cause of it is the sole seller of its product. monopoly is barriers to entry 而且其产品没有相近的替代品。 its product does not have close substitutes 为什么会产生垄断 Why Monopolies Arise 政府创造的垄断 进入障碍有三个主要来源: Government-Created Monopolies Barriers to entry have three sources: ◆关健资源由一豪企业所有 政府给予一个企业在一些市场上出售某种物品的专 门权利时,就限制了进入 ◆政府给予一个企业生产某种产品的独事的权利 The government gives a single firm the exclusive right to Governments may restrict entry by giving a single firm produce some good. the exclusive right to sell a particular good in certain ◆生产成本使一个生产者比大量生产者更有效率 markets. Costs of production make a single producer more efficient than large number of producers
1 垄断 Monopoly 第15章 Chapter 15 2 垄断 Monopoly 竞争企业是价格接受者，而垄 断企业是价格制定者。 While a competitive firm is a price taker, a monopoly firm is a price maker. 3 垄断 Monopoly 一个企业被认为是垄断，如果 A firm is considered a monopoly if …它是其产品的唯一的卖者。 it is the sole seller of its product. …而且其产品没有相近的替代品。 its product does not have close substitutes. 4 为什么会产生垄断 Why Monopolies Arise 产生垄断的根本原因是进入障碍。 The fundamental cause of monopoly is barriers to entry. 5 为什么会产生垄断 Why Monopolies Arise 进入障碍有三个主要来源： Barriers to entry have three sources: 关键资源由一家企业所有。 Ownership of a key resource. 政府给予一个企业生产某种产品的独享的权利。 The government gives a single firm the exclusive right to produce some good. 生产成本使一个生产者比大量生产者更有效率。 Costs of production make a single producer more efficient than a large number of producers. 6 政府创造的垄断 Government-Created Monopolies 当政府给予一个企业在一些市场上出售某种物品的专 门权利时，就限制了进入。 Governments may restrict entry by giving a single firm the exclusive right to sell a particular good in certain markets
政府创造的垄断 垄断资源 Government-Created Monopolies Monopoly Resources 专利和版权法是政府如何为公共利益创造 虽然关健资源的独享所有权是产生耋断的着在原 垄断的两个重要例子。 因,但实际上垄断很少产生于这种原 Patent and copyright laws are two Although exclusive ownership of a key resource is a important examples of how governmen potential souree of monopoly. in practice creates a monopoly to serve the public monopolies rarely arise for this interest 自然垄断 自然垄断 Natural Monopolies Natural Monopolies 当一个企业能以低于两个或更多企业的成本为整 当相关生产范围存在规模经济时,自然垄断就产生了 个市场供给一种物品时,这个行业是自然垄断。 A natural monopoly arises when there are economies An industry is a natural monopoly when a single of scale over the relevant range of output. firm can supply a good or service to an entire 在何一种既定的产 企业数多,每个企业的产 market at a smaller cost than could two or more For any given amount of output, a larger number of firms leads to less output per firm and higher average total cost. 作为断原因的规模经济 Economies of scale as a cause of 自然垄断 Monopoly. Natural Monopolies ◆正常情况下,垄断利润吸引了进入者进入该市 Normally, the monopolists profit attracts entrants into the market ◆与此相反,进入另一个企业拥有自然垄断的市 场却没有吸引力 ontrast,entering a market in which another firm has a natural monopoly is 平均总 unattractive. total cost
2 7 政府创造的垄断 Government-Created Monopolies 专利和版权法是政府如何为公共利益创造 垄断的两个重要例子。 Patent and copyright laws are two important examples of how government creates a monopoly to serve the public interest. 8 垄断资源 Monopoly Resources 虽然关键资源的独享所有权是产生垄断的潜在原 因，但实际上垄断很少产生于这种原因。 Although exclusive ownership of a key resource is a potential source of monopoly, in practice monopolies rarely arise for this reason. 9 自然垄断 Natural Monopolies 当一个企业能以低于两个或更多企业的成本为整 个市场供给一种物品时，这个行业是自然垄断。 An industry is a natural monopoly when a single firm can supply a good or service to an entire market at a smaller cost than could two or more firms. 10 自然垄断 Natural Monopolies 当相关生产范围存在规模经济时，自然垄断就产生了 A natural monopoly arises when there are economies of scale over the relevant range of output. 在任何一种既定的产量时，企业数量越多，每个企业的产 量越少，平均总成本越高。 For any given amount of output, a larger number of firms leads to less output per firm and higher average total cost. 11 作为垄断原因的规模经济 Economies of Scale as a Cause of Monopoly... 平均总成本 Average total cost 产量Quantity of Output 成本 Cost 0 12 自然垄断 Natural Monopolies 正常情况下，垄断利润吸引了进入者进入该市 场。 Normally, the monopolist’s profit attracts entrants into the market. 与此相反，进入另一个企业拥有自然垄断的市 场却没有吸引力。 By contrast, entering a market in which another firm has a natural monopoly is unattractive
垄断与竞争 垄断与竞争 Monopoly versus Competition Monopoly versus Competition 垄断 Monopoly 说明竞争企业与垄断者之间差别的一个方法 ◆是唯一的生产者 是考虑每个企业面恿的需求曲线 Is the sole producer ne way to view the difference between a ◆面临一条向右下方倾斜的需求曲线 competitive firm and a monopoly is to Has a downward-sloping demand curv consider the demand curve that each firm ◆是价格制定者 Is a price maker ◆降低价格以增加销售 Reduces price to increase sales 竞争与新企业的那求曲线 竞争与垄断 Demand Curves for Competitive and Competition versus Monopoly 竞争企业 Competitive Firm (a)争企业的求端 (b)新企业的求曲端 ◆是许多生产者之一 Is one of many producers ◆面临一条水平的需求曲线 Has a horizontal demand curve ◆是价格接受者 Is a price taker ◆在同一价格上想卖多少就卖多少 需求 Demand Sells as much or as little at same price uantity of 垄断者的收益 垄断者的总收益、平均收益和边际收益 A Monopoly's Revenue A M nd Marginal Revenue ◆总收益 Total Revenue TR=PX Q 批格 R=PXQ)(AR=TR/Q) ◆平均收益 Average revenue ARE TR/Q=P ◆边际收益 Marginal revenue s200 MR=ATR∠Q 53D0
3 13 垄断与竞争 Monopoly versus Competition 说明竞争企业与垄断者之间差别的一个方法 ，是考虑每个企业面对的需求曲线。 One Way to view the difference between a competitive firm and a monopoly is to consider the demand curve that each firm faces. 14 垄断与竞争 Monopoly versus Competition 垄断 Monopoly 是唯一的生产者 Is the sole producer 面临一条向右下方倾斜的需求曲线 Has a downward-sloping demand curve 是价格制定者 Is a price maker 降低价格以增加销售 Reduces price to increase sales 15 竞争与垄断 Competition versus Monopoly 竞争企业 Competitive Firm 是许多生产者之一 Is one of many producers 面临一条水平的需求曲线 Has a horizontal demand curve 是价格接受者 Is a price taker 在同一价格上想卖多少就卖多少 Sells as much or as little at same price 16 产量 Quantity of Output 需求 Demand (a) 竞争企业的需求曲线 A Competitive Firm’s Demand Curve (b) 垄断企业的需求曲线 A Monopolist’s Demand Curve 0 价格 Price 0 产量 Quantity of Output 价格Price 需求Demand 竞争与垄断企业的需求曲线 Demand Curves for Competitive and Monopoly Firms... 垄断者的收益 A Monopoly’s Revenue 总收益 Total Revenue TR = P x Q 平均收益 Average Revenue AR = TR/Q = P 边际收益 Marginal Revenue MR = ∆TR/∆Q 18 垄断者的总收益、平均收益和边际收益 A Monopoly’s Total, Average, and Marginal Revenue 数量 Quantity (Q) 价格 Price (P) 总收益 Total Revenue (TR=PxQ) 平均收益 Average Revenue (AR=TR/Q) 边际收益 Marginal Revenue (MR= ∆TR/∆Q ) 0 $11.00 $0.00 1 $10.00 $10.00 $10.00 $10.00 2 $9.00 $18.00 $9.00 $8.00 3 $8.00 $24.00 $8.00 $6.00 4 $7.00 $28.00 $7.00 $4.00 5 $6.00 $30.00 $6.00 $2.00 6 $5.00 $30.00 $5.00 $0.00 7 $4.00 $28.00 $4.00 -$2.00 8 $3.00 $24.00 $3.00 -$4.00
垄断者的边际收益 垄断者的边际收益 A Monopoly's Marginal Revenue A Monopoly,'s Marginal Revenue 当垄断者增加它的销售数量时,这对总收益Px 断者的边际收益总是小于其物品的价格。 Q有两种效应 A monopolist's marginal revenue is always less than the When a monopoly increases the amount it sells, it has two effects on total revenue(Px Q) ●求曲线是向右下方倾斜的 The demand curve is downward sloping. ◆产量效应:销售的产量越多,因此Q越大。 ◆当断者增加出售一个单 品,价格下降,从B The output effect-more output is sold, so Q 所销售的各单位中获得的收益也下降。 is higher. When a monopoly drops the price to sell one more unit, ◆价格效应:价格下降,因此P降低 the revenue received from previously sold units als decreases. The price effect-price falls, so P is lower 断者的需求和边际收益曲线 Demand and Marginal Revenue Curves 垄断者的利润最大化 for a Monopo/ Profit Maximization of a Monopoly 价Pice 使垄断者的利润最大化的产量是边际收益等于 边际成本时的产 A monopoly maximizes profit by producing the quantity at which marginal revenue equals arginal cost. 然后垄断者用需求曲线找出使消费者购买那些 数量的价格。 It then uses the demand curve to find the price that will induce consumers to buy that quantity. ntity of water 垄断者的利润最大化 比较垄断和竞争 Profit-Maximization for a Monopoly. Comparing Monopoly and 录出与这 Competition 鬼了录大 对于竞争企业来说,价格等于边际成本。 For a competitive firm, price equal marginal PE MRE MC 对于垄断企业来说,价格大于边际成本 For a monopoly firm, price exceeds 求 Demand marginal cost. P> MRE MC 录收益 Marginal I
4 19 垄断者的边际收益 A Monopoly’s Marginal Revenue 垄断者的边际收益总是小于其物品的价格。 A monopolist’s marginal revenue is always less than the price of its good. 需求曲线是向右下方倾斜的。 The demand curve is downward sloping. 当垄断者增加出售一个单位的物品，价格下降，从以 往所销售的各单位中获得的收益也下降。 When a monopoly drops the price to sell one more unit, the revenue received from previously sold units also decreases. 20 垄断者的边际收益 A Monopoly’s Marginal Revenue 当垄断者增加它的销售数量时，这对总收益(P x Q)有两种效应： When a monopoly increases the amount it sells, it has two effects on total revenue (P x Q). 产量效应：销售的产量越多，因此Q 越大。 The output effect—more output is sold, so Q is higher. 价格效应：价格下降，因此P 降低。 The price effect—price falls, so P is lower. 垄断者的需求和边际收益曲线 Demand and Marginal Revenue Curves for a Monopoly... 数量 Quantity of Water 价格Price $11 10 9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 1 2 3 4 5 67 8 边际收益 Marginal revenue 需求Demand (平均收益 average revenue) 22 垄断者的利润最大化 Profit Maximization of a Monopoly • 使垄断者的利润最大化的产量是边际收益等于 边际成本时的产量。 A monopoly maximizes profit by producing the quantity at which marginal revenue equals marginal cost. • 然后垄断者用需求曲线找出使消费者购买那些 数量的价格。 It then uses the demand curve to find the price that will induce consumers to buy that quantity. 垄断者的利润最大化 Profit-Maximization for a Monopoly... 0 QMAX Quantity Costs and Revenue 需求Demand 平均总成本 Average total cost 边际收益Marginal revenue Marginal cost A 1. 边际收益曲线与边际成本 曲线相交，决定了利润最大 化的产量 The intersection of the marginal-revenue curve revenue curve and the marginal-cost curve determines the profit-maximizing quantity... B 2. 这时需求曲线表示出与这 种数量相一致的价格 ...and then the demand curve shows the price consistent with this quantity. 垄断价格 Monopoly Price 边际成本 24 比较垄断和竞争 Comparing Monopoly and Competition • 对于竞争企业来说，价格等于边际成本。 For a competitive firm, price equals marginal cost. P = MR = MC • 对于垄断企业来说，价格大于边际成本。 For a monopoly firm, price exceeds marginal cost. P > MR = MC
断的利润 垄断的利润 The Monopolist's Profi A Monopoly's Profit 利润等于总收益减总成本 边际成本 Marginal cost Profit equals total revenue minus total costs. 利润 Profit=TR-Tc 利润 Profit=(TR/Q-Tc/Q)xQ 利润 Profit=(P-ATc)xQ 平炮总本 求 Demand Quantity 药员方场 垄断的利润 The market for druc The Monopolist's Profit 成本和收兰 Costs and 垄断者将获得经济利润,只要价格 高于平均总成本。 The monopolist will receive economic profits as long as price is 边际成本 reater than average total cost. 边际收益 Demand Quantity 垄断的福利代价 有效率的产量水平 The Welfare Cost of Monopoly The Efficient Level of output. Price 边际成本 Marginal co 与竞争企业不同,垄断企业收取的价格高于边际成 本 In contrast to a competitive firm, the monopoly 查新者的成本 harges a price above the marginal cost. 从消费者角度看,这种高价格使垄断是不合意的。 From the standpoint of consumers, this high price makes monopoly undesirable. 需求 Demand 但是,从企业所有者的角度看,高价格使垄断极为 合意。 However, from the standpoint of the owners of the Quantity firm, the high price makes monopoly very desirable
5 25 垄断的利润 A Monopoly’s Profit 利润等于总收益减总成本 Profit equals total revenue minus total costs. 利润Profit = TR - TC 利润Profit = (TR/Q - TC/Q) x Q 利润Profit = (P - ATC) x Q 垄断利润 Monopoly profit 垄断的利润 The Monopolist’s Profit... 0 Quantity Costs and Revenue 需求Demand 边际成本Marginal cost 边际收益Marginal revenue QMAX Monopoly B Price 垄断价格 E Average total cost 平均总成本 D 平均总成本 Average total cost C 成本和收益 27 垄断的利润 The Monopolist’s Profit 垄断者将获得经济利润，只要价格 高于平均总成本。 The monopolist will receive economic profits as long as price is greater than average total cost. 28 药品市场 The Market for Drugs... 成本和收益 Costs and Revenue 专利期内的 价格Price during patent life 专利到期后 的价格 Price after patent expires 垄断数量 Monopoly quantity 竞争数量 Competitive quantity 0 数量 Quantity 需求 Demand 边际成本 Marginal 边际收益 cost Marginal revenue 29 垄断的福利代价 The Welfare Cost of Monopoly • 与竞争企业不同，垄断企业收取的价格高于边际成 本。 In contrast to a competitive firm, the monopoly charges a price above the marginal cost. • 从消费者角度看，这种高价格使垄断是不合意的。 From the standpoint of consumers, this high price makes monopoly undesirable. • 但是，从企业所有者的角度看，高价格使垄断极为 合意。 However, from the standpoint of the owners of the firm, the high price makes monopoly very desirable. 30 Price 0 Quantity 边际成本Marginal cost 需求Demand (value to buyers) 效率产量 Efficient quantity 垄断者的成本 Cost to monopolist 对买者的 价值 Value to buyers 对买者的 价值 Value to buyers 垄断者的成本 Cost to monopolist 对买者的价值大于卖者的成本 Value to buyers is greater than cost to seller. 对买者的价值小于卖者的成本 Value to buyers is less than cost to seller. 有效率的产量水平 The Efficient Level of Output
无谓损失 断的无效率 The Deadweight Loss The Inefficiency of Monopoly 由于垄断者收取高于边际成本的价格,它就在 cost 消费者的支付意愿和生产者的成本之间打入了 一个禊子。 盡听价格 Because a monopoly sets its price above marginal nopoly cost cost, it places a wedge between the consumers willingness to pay and the producers cost. ◆这个楔子导致销售量小于社会最优量。 This wedge causes the quantity sold to fall short of the social optimum. 求 Demand Revenue Quantity 垄断的无效率 无谓损失 The Inefficiency of Monopoly The Deadweight Loss 垄断者生产的产量小于社会有 断引的无失类似积收引起的无预失,n 效率的产量。 to the deadweight loss caused by a tax. The monopolist produces less 这两种情况之间的差别是政府得到了税收的收入 than the socially efficient 而私人企业得到了垄断利润 The difference between the two cases is that the quantity of output. government gets the revenue from a tax, whereas a private firm gets the monopoly profit 对垄断的公共政策 用反托拉斯法增强竞争 Public Policy Toward Monopolies Increasing Competition with Antitrust Laws 政府以四种方式中的一种对垄断问题作出反应 反托拉斯法是一系列目的在于遏制垄断权力的法律的集合。 Government responds to the problem of Antitrust laws are a collection of statu monopoly in one of four ways. 努力使断行业更有竞争性。 反托拉斯法给予政府促进竞争的各种方法 Making monopolized industries more competitive. 管制空断者的行为 ◆它们允许政府阻止企业合并 Regulating the behavior of monopolies. They allow government to prevent mergers. 把一些私人垄断变为公有企业 ◆它们允许政府分解公司 ning some private monopolies into public enterprises. They allow government to break up companies. 什么也不做 ◆它们莱止公司从事使市场竞争削弱的活动 Doing nothing at all. They prevent companies from performing activities which make markets less competitive
6 31 无谓损失 The Deadweight Loss 由于垄断者收取高于边际成本的价格，它就在 消费者的支付意愿和生产者的成本之间打入了 一个楔子。 Because a monopoly sets its price above marginal cost, it places a wedge between the consumer’s willingness to pay and the producer’s cost. 这个楔子导致销售量小于社会最优量。 This wedge causes the quantity sold to fall short of the social optimum. 垄断的无效率 The Inefficiency of Monopoly... 0 Quantity 需求Demand 边际收益 Marginal Revenue 边际成本Marginal cost 垄断价格 Monopoly cost 无谓损失 Deadweight loss 效率数量 Efficient quantity 垄断数量 Monopoly quantity Price 33 垄断的无效率 The Inefficiency of Monopoly 垄断者生产的产量小于社会有 效率的产量。 The monopolist produces less than the socially efficient quantity of output. 34 无谓损失 The Deadweight Loss • 垄断引起的无谓损失类似于税收引起的无谓损失。 The deadweight loss caused by a monopoly is similar to the deadweight loss caused by a tax. • 这两种情况之间的差别是政府得到了税收的收入， 而私人企业得到了垄断利润。 The difference between the two cases is that the government gets the revenue from a tax, whereas a private firm gets the monopoly profit. 35 对垄断的公共政策 Public Policy Toward Monopolies 政府以四种方式中的一种对垄断问题作出反应： Government responds to the problem of monopoly in one of four ways. • 努力使垄断行业更有竞争性。 Making monopolized industries more competitive. • 管制垄断者的行为。 Regulating the behavior of monopolies. • 把一些私人垄断变为公有企业。 Turning some private monopolies into public enterprises. • 什么也不做。 Doing nothing at all. 36 用反托拉斯法增强竞争 Increasing Competition with Antitrust Laws • 反托拉斯法是一系列目的在于遏制垄断权力的法律的集合。 Antitrust laws are a collection of statutes aimed at curbing monopoly power. • 反托拉斯法给予政府促进竞争的各种方法。 Antitrust laws give government various ways to promote competition. 它们允许政府阻止企业合并。 They allow government to prevent mergers. 它们允许政府分解公司。 They allow government to break up companies. 它们禁止公司从事使市场竞争削弱的活动。 They prevent companies from performing activities which make markets less competitive
美国的两个重要的反托拉斯法 管制 Two Important Antitrust Laws Regulation 1890年的 Sherman反托拉斯法( Sherman 政府管制垄断者收取的价格。 Antitrust Act) Government may regulate the prices ◆减少当时强大的“托拉斯市场势力 that the monopoly charges. Reduced the market power of the large and powerful "trusts"of that time period. ◆如果价格定在等于边际成本,资源 1914年的 Clayton法( Clayton Act) 配置就将是有效率的。 ◆加强政府的权力,并使私人对此类诉讼合法化 The allocation of resourees will be Strengthened the government's powers and efficient if price is set to equal marginal cost. 自然断的边际成本定价 Marginal-Cost Pricing for a Natural 管制 Monopoly. 在实际中,管制者允许垄断者从降低成 本中以更高利润形式保留一些利益,这 种做法要求对边际成本定价的某种偏离 Average cost In practice, regulators will allow total cos monopolists to keep some of the benefits 制的价备 from lower costs in the form of higher profit, a practice that requires some 福求 Demand departure from marginal-cost pricing. 公有制 什么也不做 Public Ownership Doing Nothing 政府不是管制由私人经营的自然垄断 而是由自己经营自然垄断本身(比 如果相对于公共政策的不完善性 如,在美国,政府经营美国邮政局) 而言市场失灵的程度肯定较小, Rather than regulating a natural 那末政府可以什么也不做。 monopoly that is run by a private firm Government can do nothing at al the government can run the monopoly if the market failure is deemed itself(e.g. in the U.s the government runs the postal Service) small compared to the imperfections of public policies
7 37 美国的两个重要的反托拉斯法 Two Important Antitrust Laws • 1890年的Sherman反托拉斯法（Sherman Antitrust Act） 减少当时强大的“托拉斯”市场势力。 Reduced the market power of the large and powerful “trusts” of that time period. • 1914年的Clayton 法（Clayton Act） 加强政府的权力，并使私人对此类诉讼合法化。 Strengthened the government’s powers and authorized private lawsuits. 38 管制 Regulation 政府管制垄断者收取的价格。 Government may regulate the prices that the monopoly charges. 如果价格定在等于边际成本，资源 配置就将是有效率的。 The allocation of resources will be efficient if price is set to equal marginal cost. 39 自然垄断的边际成本定价 Marginal-Cost Pricing for a Natural Monopoly... Regulated price 受管制的价格 0 Quantity 亏损Loss Price 需求Demand 边际成本Marginal cost 平均总成本 Average total cost Average total cost 平均总成本 40 管制 Regulation 在实际中，管制者允许垄断者从降低成 本中以更高利润形式保留一些利益，这 种做法要求对边际成本定价的某种偏离 In practice, regulators will allow monopolists to keep some of the benefits from lower costs in the form of higher profit, a practice that requires some departure from marginal-cost pricing. 41 公有制 Public Ownership 政府不是管制由私人经营的自然垄断 ，而是由自己经营自然垄断本身（比 如，在美国，政府经营美国邮政局） Rather than regulating a natural monopoly that is run by a private firm, the government can run the monopoly itself. (e.g. in the U.S., the government runs the Postal Service). 42 什么也不做 Doing Nothing 如果相对于公共政策的不完善性 而言市场失灵的程度肯定较小， 那末政府可以什么也不做。 Government can do nothing at all if the market failure is deemed small compared to the imperfections of public policies
价格歧视 价格歧视 Price Discrimination Price discrimination 当一种物品在竞争市场出售时,价格歧视是不可 企业试图将同样的产品以不同的价格卖给 能的,因为有许多以市场价格出售同一种物品的 不同的顾客。这一做法就是价格歧视。 企业。企业能够实行价格歧视,它一定具有某种 Firms try to sell the same good to different Price discrimination is not possible when a good is customers for different prices. This practice sold in a competitive market since there are many is called price discrimination. firms all selling at the market price. In order to price discriminate, the firm must have some marker power. 完全价格歧视 价格歧视 Perfect Price Discrimination Price Discrimination 完全价格歧视是指这种情况:垄断者 价格歧视的两个重要效应 完全了解每个顾客的支付意愿,并对 Two important effects of price 每位顾客收取不同的价格 discrimination: Perfect price discrimination refers to ◆它可以增加垄断者的利润。 It can increase the monopolists profits the situation when the monopolist ◆它可以减少无谓损失 knows exactly the willingness to pay of It can reduce deadweight loss. each customer and can charge each customer a different price 没有价格歧视时的福利 有价格歧视时的福利 Welfare Without Price discrimination Welfare With Price Discrimination (a)单一价格垄斷者 Prie(b)完全价格峻视斯者 Monopolist with Single Price Monopolist with Perfect Price Discrimination 无损失 Deadweigl 盡斯价格利润 Profit 福求 Demand 剩会 Quantity sold Quantity Quantity
8 43 价格歧视 Price Discrimination 企业试图将同样的产品以不同的价格卖给 不同的顾客。这一做法就是价格歧视。 Firms try to sell the same good to different customers for different prices. This practice is called price discrimination. 44 价格歧视 Price Discrimination 当一种物品在竞争市场出售时，价格歧视是不可 能的，因为有许多以市场价格出售同一种物品的 企业。企业能够实行价格歧视，它一定具有某种 市场势力。 Price discrimination is not possible when a good is sold in a competitive market since there are many firms all selling at the market price. In order to price discriminate, the firm must have some market power. 45 完全价格歧视 Perfect Price Discrimination 完全价格歧视是指这种情况：垄断者 完全了解每个顾客的支付意愿，并对 每位顾客收取不同的价格。 Perfect price discrimination refers to the situation when the monopolist knows exactly the willingness to pay of each customer and can charge each customer a different price. 46 价格歧视 Price Discrimination • 价格歧视的两个重要效应： Two important effects of price discrimination: 它可以增加垄断者的利润。 It can increase the monopolist’s profits. 它可以减少无谓损失。 It can reduce deadweight loss. 47 无谓损失Deadweight loss 消费者剩余Consumer surplus 没有价格歧视时的福利 Welfare Without Price Discrimination Price 0 Quantity 利润Profit 需求Demand 边际成本Marginal cost Marginal revenue 销售量Quantity sold Monopoly price (a) 单一价格垄断者 Monopolist with Single Price 垄断价格 边际收益 48 利润 Profit 有价格歧视时的福利 Welfare With Price Discrimination Price 0 Quantity 需求Demand 边际成本Marginal cost Quantity sold (b) 完全价格歧视垄断者 Monopolist with Perfect Price Discrimination 销售量
价格歧视的例子 垄断的普遍性 Examples of Price Discrimination The Prevalence of Monopoly 垄断问题有多普遍? 电影票 Movie tickets How prevalent are the problems of monopolies? 机票价格 Airline prices ◆一方面,垄断常见 Monopolies are coml 折打券 Discount coupons 多企业对它们收取的价格都有兼种控制,因为不同企业 奖学金 Financial aid Most firms have some control over their prices because of 数量折打 Quantity discounts ◆另一方面,有相当大断势力的企业很少。 poly power are rare. ◆没有多少物品真正是教一无二的 总结 总结 Summary Summary 垄断是在其市场上为唯一卖者的企业。 A monopoly is a firm that is the sole seller in its 正如竞争企业一样,垄断企业也通过生产 它面临对其产品的向右下方倾斜的需求曲线 Like a competitive firm, a monopoly It faces a downward-sloping demand curve for maximizes profit by producing the qu s product. t which marginal cost and marginal revenue 垄断者的边际收益总是低于其物品的价格 are equaL. A monopoly's marginal revenue is always below 与竞争企业不同,垄断企业的价格高于它的 边际收益,所以它的价格高于边际成本 fits Unlike a competitive firm, its price exceeds its marginal revenue, so its price exceeds marginal cost. 总结 总结 Summary Summary 垄断者利润最大化的产量水平低于使消费着 政策制定者可以对垄断行为的无效率作出反 与生产者剩余之和最大化的 应,包括反托拉斯法 管制、或把垄断 A monopolist's profit-maximizing level of 企业改由政府经营 output is below the level that maximizes the Policymakers can respond to the inefficiencies sum of consumer and producer surplus. of monopoly behavior with antitrust laws, regulation of prices, or by turning the 垄断引起的无谓损失类似于税收引起的无谓 monopoly into a government-run enterprise. 损失 A monopoly causes deadweight losses similar 如果市场失灵肯定要小,政府可以决定什么 to the deadweight losses caused by taxes. 都不做 If the market failure is deemed small policymakers may decide to do nothing at all
9 49 价格歧视的例子 Examples of Price Discrimination • 电影票 Movie tickets • 机票价格 Airline prices • 折扣劵 Discount coupons • 奖学金 Financial aid • 数量折扣 Quantity discounts 50 垄断的普遍性 The Prevalence of Monopoly • 垄断问题有多普遍？ How prevalent are the problems of monopolies? 一方面，垄断常见 Monopolies are common. 多数企业对它们收取的价格都有某种控制，因为不同企业 的产品不完全一样。 Most firms have some control over their prices because of differentiated products. 另一方面，有相当大垄断势力的企业很少。 Firms with substantial monopoly power are rare. 没有多少物品真正是独一无二的。 Few goods are truly unique. 51 总结 Summary • 垄断是在其市场上为唯一卖者的企业。 A monopoly is a firm that is the sole seller in its market. • 它面临对其产品的向右下方倾斜的需求曲线。 It faces a downward-sloping demand curve for its product. • 垄断者的边际收益总是低于其物品的价格。 A monopoly’s marginal revenue is always below the price of its good. 52 总结 Summary • 正如竞争企业一样，垄断企业也通过生产边 际收益等于边际成本的产量来实现利润最大 化。 Like a competitive firm, a monopoly maximizes profit by producing the quantity at which marginal cost and marginal revenue are equal. • 与竞争企业不同，垄断企业的价格高于它的 边际收益，所以它的价格高于边际成本。 Unlike a competitive firm, its price exceeds its marginal revenue, so its price exceeds marginal cost. 53 总结 Summary • 垄断者利润最大化的产量水平低于使消费者 与生产者剩余之和最大化的产量。 A monopolist’s profit-maximizing level of output is below the level that maximizes the sum of consumer and producer surplus. • 垄断引起的无谓损失类似于税收引起的无谓 损失。 A monopoly causes deadweight losses similar to the deadweight losses caused by taxes. 54 总结 Summary • 政策制定者可以对垄断行为的无效率作出反 应，包括反托拉斯法、价格管制、或把垄断 企业改由政府经营。 Policymakers can respond to the inefficiencies of monopoly behavior with antitrust laws, regulation of prices, or by turning the monopoly into a government-run enterprise. • 如果市场失灵肯定要小，政府可以决定什么 都不做。 If the market failure is deemed small, policymakers may decide to do nothing at all
总结 垄断者可以通过根据买者的支付意愿对同 种物品收取 价格来增加利润。 Monopolists can raise their profits by charging different prices to different buyers based on their willingness to pay 价格歧视可以提高经济福利和减少无谓损 Price discrimination can raise economic welfare and lessen deadweight losses
10 55 总结 Summary • 垄断者可以通过根据买者的支付意愿对同 一种物品收取不同的价格来增加利润。 Monopolists can raise their profits by charging different prices to different buyers based on their willingness to pay. • 价格歧视可以提高经济福利和减少无谓损 失。 Price discrimination can raise economic welfare and lessen deadweight losses