国际经济学-克鲁格曼英文版课件-nobel08ch06.pptVIP

Chapter 6 Economies of Scale, Imperfect Competition, and International Trade Preview Types of economies of scale Types of imperfect competition Oligopoly and monopoly Monopolistic competition Monopolistic competition and trade Inter-industry trade and intra-industry trade Dumping External economies of scale and trade Introduction When defining comparative advantage, the Ricardian and Heckscher-Ohlin models assume that production processes have constant returns to scale: When factors of production change at a certain rate, output increases at the same rate. For example, if all factors of production are doubled then output will also double. But a firm or industry may have increasing returns to scale or economies of scale: When factors of production change at a certain rate, output increases at a faster rate. A larger scale is more efficient: the cost per unit of output falls as a firm or industry increases output. Introduction (cont.) The Ricardian and Heckscher-Ohlin models also rely on competition to predict that all income from production is paid to owners of factors of production: no “excess” or monopoly profits exist. But when economies of scale exist, large firms may be more efficient than small firms, and the industry may consist of a monopoly or a few large firms. Production may be imperfectly competitive in the sense that excess or monopoly profits are captured by large firms. Types of Economies of Scale Economies of scale could mean either that larger firms or a larger industry is more efficient. External economies of scale occur when cost per unit of output depends on the size of the industry. Internal economies of scale occur when the cost per unit of output depends on the size of a firm. Types of Economies of Scale (cont.) External economies of scale may result if a larger industry allows for more efficient provision of services or equipment to firms in the industry. Many small firms that are competitive may comprise a large industry and benefit when