1. Monopolistic Competition and Oligopoly

2. Monopolistic Competition A monopolistically competitive industry has the following characteristics: A large number of firms No barriers to entry Product differentiation

3. Monopolistic Competition Monopolistic competition is a common form of industry (market) structure in the United States, characterized by a large number of firms, none of which can influence market price by virtue of size alone. Some degree of market power is achieved by firms producing differentiated products. New firms can enter and established firms can exit such an industry with ease.

4. Nine Industries with Characteristics of Monopolistic Competition

5. Product Differentiation, Advertising, and Social Welfare

6. The Case for Product Differentiation and Advertising The advocates of free and open competition believe that differentiated products and advertising give the market system its vitality and are the basis of its power. Product differentiation helps to ensure high quality and efficient production.

7. The Case for Product Differentiation and Advertising Advertising provides consumers with the valuable information on product availability, quality, and price that they need to make efficient choices in the market place.

8. The Case Against Product Differentiation and Advertising Critics of product differentiation and advertising argue that they amount to nothing more than waste and inefficiency. Enormous sums are spent to create minute, meaningless, and possibly nonexistent differences among products.

9. The Case Against Product Differentiation and Advertising Advertising raises the cost of products and frequently contains very little information. Often, it is merely an annoyance. People exist to satisfy the needs of the economy, not vice versa. Advertising can lead to unproductive warfare and may serve as a barrier to entry, thus reducing real competition.

10. Product Differentiation Reduces the Elasticity of Demand Facing a Firm Based on the availability of substitutes, the demand curve faced by a monopolistic competitor is likely to be less elastic than the demand curve faced by a perfectly competitive firm, and likely to be more elastic than the demand curve faced by a monopoly.

12. Monopolistic Competition in the Long-Run The firm’s demand curve must end up tangent to its average total cost curve for profits to equal zero. This is the condition for long-run equilibrium in a monopolistically competitive industry.

14. Ten Highly Concentrated Industries

15. Oligopoly Models All kinds of oligopoly have one thing in common: The behavior of any given oligopolistic firm depends on the behavior of the other firms in the industry comprising the oligopoly.

16. The Collusion Model A group of firms that gets together and makes price and output decisions jointly is called a cartel. Collusion occurs when price- and quantity-fixing agreements are explicit. Tacit collusion occurs when firms end up fixing price without a specific agreement, or when agreements are implicit.

17. The Cournot Model The Cournot model is a model of a two-firm industry (duopoly) in which a series of output-adjustment decisions leads to a final level of output between the output that would prevail if the market were organized competitively and the output that would be set by a monopoly.

18. The Kinked Demand Curve Model The kinked demand model is a model of oligopoly in which the demand curve facing each individual firm has a “kink” in it. The kink follows from the assumption that competitive firms will follow if a single firm cuts price but will not follow if a single firm raises price.

19. The Kinked Demand Curve Model Above P*, an increase in price, which is not followed by competitors, results in a large decrease in the firm’s quantity demanded (demand is elastic). Below P*, price decreases are followed by competitors so the firm does not gain as much quantity demanded (demand is inelastic).

20. The Price-Leadership Model Price-leadership is a form of oligopoly in which one dominant firm sets prices and all the smaller firms in the industry follow its pricing policy.

21. The Price-Leadership Model Assumptions of the price-leadership model: The industry is made up of one large firm and a number of smaller, competitive firms; The dominant firm maximizes profit subject to the constraint of market demand and subject to the behavior of the smaller firms; The dominant firm allows the smaller firms to sell all they want at the price the leader has set.

22. The Price-Leadership Model Outcome of the price-leadership model: The quantity demanded in the industry is split between the dominant firm and the group of smaller firms. This division of output is determined by the amount of market power that the dominant firm has. The dominant firm has an incentive to push smaller firms out of the industry in order to establish a monopoly.

23. Predatory Pricing The practice of a large, powerful firm driving smaller firms out of the market by temporarily selling at an artificially low price is called predatory pricing. Such behavior became illegal in the United States with the passage of antimonopoly legislation around the turn of the century.

24. Game Theory Game theory analyzes oligopolistic behavior as a complex series of strategic moves and reactive countermoves among rival firms. In game theory, firms are assumed to anticipate rival reactions.

28. Oligopoly is Consistent witha Variety of Behaviors The only necessary condition of oligopoly is that firms are large enough to have some control over price. Oligopolies are concentrated industries. At one extreme is the cartel, in essence, acting as a monopolist. At the other extreme, firms compete for small contestable markets in response to observed profits. In between are a number of alternative models, all of which stress the interdependence of oligopolistic firms.

29. Oligopoly and Economic Performance Oligopolies, or concentrated industries, are likely to be inefficient for the following reasons: They are likely to price above marginal cost. This means that there would be underproduction from society’s point of view. Strategic behavior can force firms into deadlocks that waste resources. Product differentiation and advertising may pose a real danger of waste and inefficiency.

30. The Role of Government The Celler-Kefauver Act of 1950 extended the government’s authority to ban vertical and conglomerate mergers. The Herfindahl-Hirschman Index (HHI) is a mathematical calculation that uses market share figures to determine whether or not a proposed merger will be challenged by the government.

31. Regulation of Mergers

32. Department of Justice Merger Guidelines (revised 1984)