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