寡头和垄断竞争

,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,寡头和垄断竞争,第10章,1,不完全竞争者的行为,10.1,2,市场势力,Market power,signifies (表示) the degree of control that a firm or a small number of firms has over the price and production decisions in an industry.,The most common measure of market power is the,four-firm concentration ratio,.,3,Firm Output,Firm 125,Firm 220,Firm 315,Firm 410,Firm 5 8,Firm 6 7,Firm 7 5,Firm 8 5,Firm 9 3,Firm 10 2,=70,4企业集中度,Concentration Ratios:,c,4,=,q,1,+ q,2,+ q,3,+q,4,25+20+15+10,100,Q,=,=,70%,4,Cigarettes,Household refrigerators,Electric light bulbs,Motor vehicles,Greeting cards,Blast furnaces,Screw products,5%_4%,Tools, dies, and jigs,3%_2%,93%,82%,86%,84%,84%,37%,7%,16%,8%,7%,4%,21%,4 largest companies,Next 4 largest companies,5,集中度测定时要注意的,Conventional concentration measures include only domestic production and exclude imports.,Conventional concentration measures also ignore the growing impact of competition from other industries.,6,不完全竞争的性质,Economists have found that three major factors are present in imperfectly competitive markets:,Costs,Barriers to competition,Strategic interaction,(,策略互动,),7,不完全竞争的结果,Inefficient allocation of resources:,P MC,High levels of,R&D,spending per dollar of sales.,8,不完全竞争的理论,Three of the most important cases of imperfect competition:,Collusive oligopoly,(,合谋寡头,),Monopolistic competition,Small-number oligopoly,9,策略互动,Strategic interaction,is a term that describes how each firms business strategy depends on their rivals strategies.,As the number of firms in an industry shrink (减少), each firm is more likely to base pricing and output decisions on how other firms are likely to respond.,10,寡头的合作与非合作选择,When there are only a small number of firms in a market, they have a choice between,cooperative,(合作) and,noncooperative,(非合作) behavior.,11,合谋,Collusion occurs when one or more firms jointly (共同地) set prices or outputs, divide the market among themselves, or make other business decisions jointly.,Such collusion can be either,explicit,or,tacit,(公开的或默许的).,12,公开合谋,One example of explicit (清楚的，公开的) collusion would be that of the Gilded Age oligopolists (市场供应垄断者) in the early years of American capitalism.,These oligopolists formed trusts or cartels (托拉斯或卡特尔) to set prices.,13,美国的反托拉斯法,谢尔曼法是在1890年通过的，100多年来基本未变。它有两条主要条款：,第1条,，任何限制州际或与外国的贸易和商业的合同、托拉斯或其他形式的合并或阴谋，都是非法的。,第2条,，任何将实行垄断、或企图实行垄断、或与他人合并或密谋策划以谋求对州际或与外国的贸易和商业的任一部分实行垄断的人，均将被视为犯罪。,14,以后的变化,1974年，对谢尔曼法进行了修正，判违法以重罪而不是轻罪。,现在，公司可被罚款最高达100万美元，个人可被罚款最高达10万美元，且可被判最高达三年的监禁。,另外，在民事诉讼中，企业和个人还可能被处以三倍于因为反托拉斯法而造成的损失的赔偿。,15,反托拉斯法,After the American public rose up (起来，起义) and demanded the passage of tough antitrust laws in 1910, cartels and explicit collusion became illegal in the United States .,16,例子：,月亮盈亏阴谋,1960年，通用、西屋等若干公司的高层管理者制定了一个固定大型变电、发电等设备价格的阴谋。,17,每个合谋的公司按预先约定的月亮盈亏状况轮流轮流“坐庄”，谁坐庄就轮到谁中标。,轮到中标的公司给出比竞争状况下要高的投标价格，而没轮到中标的公司则投出更高的价格，以保证约定的公司中标。,如何运作,18,最后的结局,后来，阴谋败露，有7名被告坐牢30天，企业罚款200万元。因1900个当事人提出了诉讼，企业为此支付赔偿金4亿美元以上。,19,默许合谋,The broader problem is with,implicit,or,tacit collusion,that arises precisely because explicit collusion is illegal.,Price Leader,20,有效合谋的障碍,First, collusion is illegal.,Second, firms may “cheat” on the agreement by cutting their price to selected customers.,Third, many companies face intensive competition from foreign firms as well as domestic companies.,21,合谋后的欺骗价值,产量,如果其他人保持价格不变,搞欺骗的企业的好处,价格,如果所有企业价格同时变化,22,1973 和 1974 年间, OPEC的成员联合起来， 因美国支持以色列而对美国实施石油禁运，导致油价达到原来的四倍多。,1970 年代的石油价格冲击后，汽车转向小型化和节油型的，住家也更注重房子的保温的隔热，商业也采用新的技术以大幅减少能源的消耗。总之，各方面都采取了种种措施来减少对石油的需求。,OPEC 欺骗的例子,23,在供给方面，高的油价刺激了发掘新的石油资源勘探，非OPEC成员如挪威、墨西哥等国家进入世界石油市场。,与此同时,24,更严重的问题不是来自石油供求方面的变化，而是OPEC成员内部大范围的欺骗行为，象伊朗、伊拉克、利比亚等国。 甚至不惜爆发战争。,除此之外,25,在扣除物价变化的影响后，1990年代的石油价格实际上低于1970年代初OPEC抬高油价之前的水平。,结果,26,威胁是否可置信,OPEC has no effective enforcement mechanism to police its agreements.,It has little effective way to punish any members who do cheat on the collusive bargain (契约).,27,在钢铁行业重新建立价格纪律,摘自克雷格彼得森：管理经济学（第4版），308-309页,在20世纪60年代前，美国钢铁公司一直是钢铁行业中的定价领袖。可是，1962年，美国钢铁公司宣布的一次涨价引起了许多顾客和政府高级官员，特别是肯尼迪总统的批评，使得它不大愿意再充当价格领袖。结果，这一行业就从支配企业价格领导模式演变到气压表式价格领导模式。,28,新的模式是一家企业首先试探性地宣布价格变动，然后美国钢铁公司通过其反应或者对这种变动予以确认，或者加以拒绝。,1968年，美国钢铁公司发现它的市场份额在缩小。因此，它秘密地对大顾客降价。这一行动很快被伯利恒钢铁公司察觉，伯利恒公司就把钢铁价格从每吨113.50美元降到88.50美元。在3周内，所有其他主要钢铁生产者，包括美国钢铁公司在内，都跟随伯利恒公司降价。,29,较低的行业价格使所有的行业成员都无法获利。因此，美国钢铁公司宣布将提高价格，表示愿意停止价格战。伯利恒公司等了9天，提出了一个比美国钢铁公司略低的价格作为应答。美国钢铁公司很快把价格降到伯利恒公司的水平。注意到美国钢铁公司愿意重新遵守行业规则后，伯利恒公司宣布将价格提高到每吨125美元。所有其他主要生产者很快跟上，行业纪律得到了恢复。注意，每吨125美元的价格比原来的113.50美元高。,30,垄断竞争,Monopolistic competition resembles perfect competition in three ways:,1.,There many buyers and sellers,2.,Entry and exit are easy,3.,Firms take other firms prices as given.,31,产品差异的需求特点,The difference from perfect competition is,product differentiation,(产品差异).,Product differentiation leads to a,downward slope in each sellers demand curve,.,32,垄断竞争与寡头的比较,There are three key differences between oligopoly and monopolistic competition.,1.,A monopolistically competitive industry is relatively unconcentrated.,2.,Collusions are impossible.,3.,There is no feeling of mutual interdependence among firms.,33,回顾多数竞争与少数竞争差异,1人,少数,多数,无数,垄断,寡头,垄断竞争,完全竞争,盯住对手,关注自己,34,短期和长期的盈利,In the short run, monopolistic competitors may well earn monopoly profits under certain circumstances.,In long run equilibrium, economic profits in the industry will be driven to zero just as in perfect competition.,35,垄断竞争企业的短期定价,从短期来看，垄断竞争企业的经济利润可能大于零。,Quantity,Price,MC,AC,MR,Profit,d,d,36,如果利润为正,垄断竞争,行业,自由进入,需求,同时，利润,市场份额减少,37,如果利润为负,垄断竞争,行业,需求,同时，利润,自由退出,市场份额增加,38,垄断竞争企业的长期均衡,从长期来看，垄断竞争企业的经济利润等于零。,Quantity,Price,MC,AC,MR,d,d,39,A,Productive efficiency is not realized,because production occurs at point A where the average total cost exceeds the minimum attainable (,可达到的,) cost.,40,A,In the long-run equilibrium for monopolistic competition,prices are above marginal costs,but economic profits have been driven down to zero.,Some critics believe that monopolistic competition is inherently (固有地) inefficient, even though profits are zero in the long run.,41,非价格竞争和过度广告,The fact that the monopolistic competition is both,allocatively,and productively inefficient relative to the perfect competition result is not the only problem with market performance.,At least some economists argue that monopolistic competition leads to both excessive advertising and needless brand proliferation (,增殖,).,42,多样化是好事,Reducing the number of monopolistic competitors, while cutting costs, might well end up lowering consumer welfare because it would reduce the diversity (多样性) of available goods and services.,43,少数竞争,Competition among the few forces firms to take into account competitors reactions to price and output deviations (背离) and brings strategic (战略的) considerations into their markets.,This analysis is the province of game theory (博弈论).,44,博弈论,少数竞争者之间具有互动性的行为或结果，应该用博弈论的方法来研究。,博弈论,（,game theory,）是用于分析两个和两个以上的参与者在相互作用的情况下，选择行动或策略及其影响的一种理论。,45,控制、创新和信息,10.2,46,说明,这部分内容讲述实际经济中的一些特殊情形：,大公司中的所有权与控制权分离；,实际中的成本加成定价法；,不完全竞争的创新作用；,关于信息的一些经济学问题。,47,大公司的所有权与控制权分离,In 1996, more than 2.3 million people owned AT&Ts shares.,Because the stock of large companies is so widely dispersed (被分散的), ownership is typically divorced from control.,48,潜在利益冲突之一,First, insiders (内部人员) may vote themselves large salaries, expense accounts, bonuses (奖金), and generous retirement pensions (退休金) at the stockholders expense.,49,潜在利益冲突之二,Second, the managers of a company have an understandable tendency to hold on to profits and use them to expand the size of the company instead of paying them out as dividends.,50,潜在利益冲突之三,Third, managers are often primarily interested in maintaining the smooth operation of the organization rather than running major risks and making revolutionary changes.,However, the decisions of managers cannot diverge (偏离) too far from profit maximization.,51,理性和经验方法,In the real world, people have limited resources and information to make decisions, so firms or consumers often exhibit,bounded rationality,(有限理性). This means that they usually strive to make a good decision, rather than waste resources hunting for (追逐) the best decision.,52,说明,有限理性是考虑信息和资源因素后，追求“效用最大化”和“利润最大化”的一种行为方式。,如何将复杂的问题简单化或规则化，是管理的一种技巧。,53,成本加成定价,成本加成定价：在定价实践中，使用最多的是一种叫做成本加成的定价方法。它的典型做法分为两步：,第一,，估计每单位产量的成本，一般以企业生产能力的2/34/5计算平均成本。,第二,，,价格平均成本（1利润加成率）,确定利润加成水平的原则是需求价格弹性越小，加成率就越大，反之就越,小。,54,零售杂货店的加成,摘自：埃德温曼斯菲尔德，管理经济学第516页,产品,加成率,产品,加成率,咖啡,5%,冻肉,30%,软饮料,5%,新鲜水果,45%,早餐谷类食品,10%,新鲜蔬菜,45%,汤类,10%,调味品,50%,冰激凌,20%,专卖药品,50%,55,成本加成定价是否与边际定价原则冲突?,利用勒纳公式可以得到，公司若以利润最大化为定价原则，,当达到利润最大时,，以下关系成立：,价格 = 边际成本(1 +,需求的价格弹性 - 1,1,),56,对应关系,考虑到,边际成本平均成本,，那么企业只要是以利润为目标，就应该有,价格 = 边际成本(1 +,需求的价格弹性 - 1,1,),需求的价格弹性 - 1,1,= 利润加成率,57,熊彼特的观点,Shumpeter argued that the essence (本质) of economic development is innovation and that monopolists (专利者) in fact are the wellsprings (源泉) of innovation (革新) in a capitalist economy.,Joseph Schumpeter,1883-1950,58,垄断带来进步？,由于垄断能够赚得比竞争行业更多的利润，因此能够将更多的资金用于长期研究与开发活动。,垄断也能够有更多的资金从事技术创新和扩散的投资。,59,规模与研发-销售额比率（美）,公司规模,研发-销售额比率 (%),研发额（10亿美元） 1993,(雇员数),1983,1993,少于 500,2.2,3.6,13.9,500 to 999,na,2.7,3.0,1,000 to 4,999,2.0,2.4,12.2,5,000 to 9,999,1.3,2.7,8.3,10,000 to 24,999,2.3,2.5,12.6,25,000 或以上,3.4,3.6,45.7,60,主要结论,个人和小企业在发明创新中起了重要的作用。,熊彼特关于企业越大，创新投入越多的见解并不是没有争议的。,市场结构与创新之间的关系也不是简单对应的。,61,动态效率,Dynamic efficiency,measures the rate of technological change and innovation in an industry.,62,相反的观点,While the monopolist may have deep pockets (财富) to spend on developing new technologies, that same monopolist has little incentive (动机) in the absence of competitors to introduce the technology so technological progress is actually slowed.,63,信息经济学,Because information is costly to produce but cheap to reproduce, markets in information are subject to severe market failures (市场失灵).,The inability of firms to capture the full monetary value of their inventions (发明) is called,inappropriability,(非专用性).,64,知识产权,The purpose of intellectual property rights (知识产权) is to give the owner special protection against the material being copied and used by others without compensation (补偿) to the owner or original creator (创作者).,65,专利,Patent,is a monopoly over the use of an invention conveyed (转让) by a government for a limited period of time, currently 20 years.,The government increase the degree of appropriability (专用性) and thereby increase the incentives for people to invent useful new products.,66,说明,专利是关于垄断与竞争优劣之争的一个最好的例子。,现实中的事物总有其两面性：垄断竞争和寡头垄断在效率损失的同时却带来了产品的多样化和技术进步。,评价垄断问题应当从生产力的量和质两方面考虑，前者可以归之为实证问题，后者可以归之为规范问题。,67,知识产权问题,知识产权在垄断与效率方面的冲突更为严重。,一般而言，知识产品的生产成本比物质产品的更高，而复制的成本却更低。从效率的角度看，应该允许大量复制，直到价格等于复制成本；从鼓励生产的角度看，则应该定较高的价格（或给予较长时间的产权保护）。,68,不完全竞争的资产负债表,10.3,69,不完全竞争的经济成本,100,200,MC=AC,D,D,Output,Price, MC, AC,6,当没有外部性时，定价100，有,P = MC,，表示社会生产某物品付出的边际成本等于消费该物品所得到的边际效用。,70,垄断引起的经济损失,100,200,MC=AC,D,D,Output,Price, MC, AC,6,150,E,B,若垄断，定价150，有,P MC,，表示社会生产某物品付出的边际成本小于消费该物品所得到的边际效用，导致社会损失,ABE,面积的利益（消费者剩余）。,MR,A,71,说明,用图中三角形面积量度净福利损失(deadweight loss，无谓的损失)应满足以下条件：,没有外部性；,人们的货币开支是合理的；,其他行业是完全竞争的。,72,MC,D,D,Output,Price, MC,E,B,MR,A,观点扩展,deadweight loss,73,垄断成本的经验研究,Early studies set the total deadweight loss from monopoly at less than 0.1 percent of GDP.,More recent studies have calculated that the deadweight welfare loss lies somewhere between 0.5 and 2 percent of gross national product.,74,相反的观点,The most important reservation (保留) about this approach (方法) is that it ignores the impact of market structure upon technological advance or “dynamic efficiency.”,According to the Schumpeterian hypothesis, imperfect competition actually promotes invention and technological change and reduces costs.,75,干预的策略,1. 反托拉斯政策 (antitrust policy)；,2. 鼓励竞争 (encouraging competition)；,3. 管制 (regulation)；,4. 政府所有 (government ownership)；,5. 价格控制 (price control)；,6. 税收 (taxes)。,76,市场经济的一些基本原则,Remove government constraints (约束) to competition.,Remember that “the tariff (关税) is the mother of monopoly.”,Promote vigorous (有力的) competition from foreign firms.,77,市场经济的一些基本原则(2),Use auctions (拍卖) and competitive bidding (投标) whenever possible.,Dont try to second-guess (预言) future technological trends.,Encourage small businesses to challenge established firms.,78,End Of Lesson,79,