曼昆《经济学原理》2-3(EnglishVersion).ppt

2 Thinking Like an Economist 主要内容：经济学的研究方法 （科学研究/政策研究） 重点：生产可能性曲线（PPF）的特征、经济学意义及应用 学完本章后，你应该： 了解经济学的基本假设 掌握两个基本的经济学模型 能够用PPF解释稀缺性、效率、权衡取舍、机会成本、经济增长等5个概念 能够用PPF说明贸易的好处 Thinking Like an Economist Every field of study has its own terminology Economics trains you to. . . . Think in terms of alternatives. Evaluate the cost of individual and social choices. Examine and understand how certain events and issues are related. The economic way of thinking . . . Involves thinking analytically and objectively. Makes use of the scientific method. The Scientific Method: Observation, Theory, and More Observation Uses abstract models to help explain how a complex, real world operates. Develops theories, collects, and analyzes data to evaluate the theories. The Role of Assumptions Economists make assumptions in order to make the world easier to understand. The art in scientific thinking is deciding which assumptions to make. Economists use different assumptions to answer different questions. Economic Models Economists use models to simplify reality in order to improve our understanding of the world Two of the most basic economic models include: The Circular Flow Diagram The Production Possibilities Frontier Our First Model: The Circular-Flow Diagram The circular-flow diagram is a visual model of the economy that shows how dollars flow through markets among households and firms. Figure 1 The Circular Flow Our First Model: The Circular-Flow Diagram Firms Produce and sell goods and services Hire and use factors of production Households Buy and consume goods and services Own and sell factors of production Our First Model: The Circular-Flow Diagram Markets for Goods and Services Firms sell Households buy Markets for Factors of Production Households sell Firms buy Our First Model: The Circular-Flow Diagram Factors of Production Inputs used to produce goods and services Land, labor, and capital Our Second Model: The Production Possibilities Frontier The production pos