microeconomicoligopoly(编辑修改稿)

microeconomicoligopoly(编辑修改稿)内容摘要：

f chicken is for one firm to do the Ramp。 D. But we cannot tell which firm will do the Ramp。 D and which will not. 169。 2020 Pearson AddisonWesley Repeated Games and Sequential Games A Repeated Duopoly Game If a game is played repeatedly, it is possible for duopolists to successfully collude and make a monopoly profit. If the players take turns and move sequentially (rather than simultaneously as in the prisoner’s dilemma), many outes are possible. In a repeated prisoners’ dilemma duopoly game, additional punishment strategies enable the firms to ply and achieve a cooperative equilibrium, in which the firms make and share the monopoly profit. 169。 2020 Pearson AddisonWesley One possible punishment strategy is a titfortat strategy. A titfortat strategy is one in which one player cooperates this period if the other player cooperated in the previous period but cheats in the current period if the other player cheated in the previous period. A more severe punishment strategy is a trigger strategy. A trigger strategy is one in which a player cooperates if the other player cooperates but plays the Nash equilibrium strategy forever thereafter if the other player cheats. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley Table shows that a titfortat strategy is sufficient to produce a cooperative equilibrium in a repeated duopoly game. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley Games and Price Wars Price wars might result from a titfortat strategy where there is an additional plication—uncertainty about changes in demand. A fall in demand might lower the price and bring forth a round of titfortat punishment. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley A Sequential Entry Game in a Contestable Market In a contestable market—a market in which firms can enter and leave so easily that firms in the market face petition from potential entrants—firms play a sequential entry game. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley Figure shows the game tree for a sequential entry game in a contestable market. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley In the first stage, Agile decides whether to set the monopoly price or the petitive price. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley In the second stage, Wanabe decides whether to enter or stay out. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley In the equilibrium of this entry game, Agile sets a petitive price and makes zero economic profit to keep Wanabe out. A less costly strategy is limit pricing, which sets the price at the highest level that is consistent with keeping the potential entrant out. Repeated Games and Sequential Games 169。 2020 Pearson AddisonWesley Antitrust Law Antitrust law provides an alternative way in which the government may influence the marketplace. Antitrust law is the law that regulates oligopolies and prevents them from being monopolies or behaving like monopolies. The Antitrust Laws The two main antitrust laws are The Sherman Act, 1890 The Clayton Act, 1914 169。 2020 Pearson AddisonWesley Antitrust Law The Sherman Act outlawed any “bination, trust, or conspiracy that restricts interstate trade,” and prohibited the “attempt to monopolize.” 169。 2020 Pearson AddisonWesley A wave of merger activities at the beginning of the twentieth century produced a stronger antitrust law, the Clayton Act, and created the Federal Trade Commission. The Clayton Act The Clayton Act made illegal specific business practices such as price discrimination, interlocking directorships, and acquisition of a petitor’s shares if the practices “substantially lessen petition or create monopoly.” Antitrust Law 169。 2020 Pearson AddisonWesley Table (next slide) summarizes the Clayton Act and its amendments, the RobinsonPatman Act passed in 1936 and the CellarKefauver Act passed in 1950. The Federal Trade Commission, formed in 1914, looks for cases of “unfair methods of petition and unfair or deceptive business practices.” Antitrust Law 169。 2020 Pearson AddisonWesley Antitrust Law 169。 2020 Pearson AddisonWesley Price Fixing Always Illegal Price fixing is always a violation of the antitrust law. If the Justice Department can prove the existence of price fixing, there is no defense. Antitrust Law 169。 2020 Pearson AddisonWesley Three Antitrust Policy Debates But some practices are more controversial and generate debate. Three of them are  Resale price maintenance  Tying arrangements  Predatory pricing Antitrust Law 169。 2020 Pearson AddisonWesley Resale Price Maintenance Most manufacturers sell their product to the final consumer through a wholesale and retail distribution chain. Resale price maintenance occurs when a manufacturer agrees with a distributor on the price at which the product will be resold. Resale price maintenance is inefficient if it promotes monopoly pricing. But resale price maintenance can be efficient if it provides retailers with an incentive to provide an efficient level of retail service in selling a product. Antitrust Law 169。 2020 Pearson AddisonWesley Tying Arrangements A tying arrangement is an agreement to sell one product only if the buyer agrees to buy another different product as well. Some people argue that by tying, a firm can make a larger profit. Where buyers have a differing willingness to pay for the separate items, a firm can price discriminate and take a larger amount of the consumer surplus by tying. Antitrust Law 169。 2020 Pearson AddisonWesley Predatory Pricing Predatory pricing is setting a low price to drive petitors out of business with the intention of then setting the monopoly price. Economists are skeptical th。