曼昆 经济学原理 第二章 像经济学家那样思考

曼昆 经济学原理 第二章 像经济学家那样思考，分为介绍了The Role of Assumptions circular-flow diagram、The Production Possibilities Frontier、Microeconomics and Macroeconomics、Positive versus Normative Analysis.

CHAPTER 2 THINKING LIKE AN ECONOMIST

• The Role of Assumptions
  • Economists make assumptions for the same reason: Assumptions can simplify the complex world and make it easier to understand.
  • we can focus our thinking on the essence of the problem.
• circular-flow diagram
• The Production Possibilities Frontier
  • The production possibilities frontier is a graph that shows the various combinations of output—in this case, cars and computers—that the economy can possibly produce given the available factors of production and the available production technology that firms use to turn these factors into output.
  • An outcome is said to be efficient if the economy is getting all it can from the scarce resources it has available. Points on (rather than inside) the production possibilities frontier represent efficient levels of production.
  • The production possibilities frontier simplifies a complex economy to highlight some basic but powerful ideas: scarcity, efficiency, trade-offs, opportunity cost, and economic growth. As you study economics, these ideas will recur in various forms. The production possibilities frontier offers one simple way of thinking about them.
• Microeconomics and Macroeconomics
  • Microeconomics is the study of how households and firms make decisions and how they interact in specific markets.
  • Macroeconomics is the study of economywide phenomena. including inflation, unemployment, and economic growth
• Positive versus Normative Analysis
  • positive statements claims that attempt to describe the world as it is
  • normative statements claims that attempt to prescribe how the world should be