1、,Thinking Like an Economist 像经济学家一样思考,Chapter 2,Every field of study has its own terminology,Mathematics,Psychology,Law,每个研究领域都有自己的语言,数学,心理学,法律,Every field of study has its own terminology,Economics,Supply,Demand,Elasticity,Consumer Surplus,Comparative advantage,Opportunity cost,Deadweight loss,每个研究
2、领域都有自己的语言,经济学,供给,需求,弹性,消费者剩余,比较优势,机会成本,无谓损失,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.,经济学训练你. . . .,从不同的角度思考问题。 评估个人和社会选择的成本。 检查和理解一些事件和问题是如何相互关联的。,The Economist
3、 as a Scientist 作为科学家的经济学家,The economic way of thinking . . .经济学思考方法 Involves thinking analytically and objectively.客观地分析与思考。 Makes use of the scientific method.利用科学的方法。,The Scientific Method,Uses abstract models to help explain how a complex, real world operates. Develops theories, collects, and an
4、alyzes data to prove the theories.,Observation, Theory and More Observation!,科学方法,利用抽象的模型帮助解释复杂的真实世界如何运行。 形成理论，收集并分析数据来验证理论。,观察, 理论 ，更多的观察,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
5、to make.Economists use different assumptions to answer different questions.,假设的作用,为了使这个世界更容易理解，经济学家做一些假设。科学思考的艺术就是决定作出什么样的假设。经济学家利用不同的假设来回答不同的问题。,The Economic Way of Thinking,Includes developing abstract models from theories and the analysis of the models. Uses two approaches:,Descriptive (reporting
6、 facts, etc.) Analytical (abstract reasoning),经济学思考方法,利用理论建立抽象的模型，然后进一步分析模型。 利用两种方法:,描述性的方法 (报告实情等) 分析性的方法 (抽象推理),Economic Models,Economists use models to simplify reality in order to improve our understanding of the worldTwo of the most basic economic models include:,The Circular Flow Model,The Pro
7、duction Possibilities Frontier,经济模型,经济学家利用模型来简化真实世界，使我们更好地理解这个世界。两个最基本的经济学模型是：,循环流向图,生产可能性边界,The Circular-Flow Model 经济循环流向图,The circular-flow model is a simple way to visually show the economic transactions that occur between households and firms in the economy. 循环流向图一个直观地说明一个经济体内家庭和企业之间的经济交易行为的简单方
8、式。,The Circular-Flow Diagram,Firms,Households,Market for Factors of Production,Market for Goods and Services,经济循环图,企业,家庭,生产要素 市场,物品与劳务 市场,Figure 1 The Circular Flow,Copyright 2004 South-Western,Spending,Revenue,Income,= Flow of inputs,and outputs,= Flow of dollars,The Circular-Flow Diagram,Household
9、sBuy and consume goods and servicesOwn and sell factors of production,FirmsProduce and sell goods and servicesHire and use factors of production,经济循环流向图,家庭购买并消费物品与劳务拥有并出售所有生产要素,企业生产并出售物品与劳务雇佣并使用生产要素,The Circular-Flow Diagram,Markets for Factors of ProductionHouseholds sellFirms buy,Markets for Goods
10、 & ServicesFirms sellHouseholds buy,经济循环图,生产要素市场家庭出售企业购买,物品与劳务市场企业出售家庭购买,The Circular-Flow Diagram 经济循环图,Factors of Production 生产要素Inputs used to produce goods and services用于生产物品与劳务的投入Land, labor, and capital土地、劳动和资本,The Production Possibilities Frontier,The production possibilities frontier is a gr
11、aph showing the various combinations of output that the economy can possibly produce given the available factors of production and technology.,生产可能性边界,生产可能性边界 表示一个经济在可得到的生产要素与生产技术既定时所能生产的产量的各种组合的图形。,The Production Possibilities Frontier 生产可能性边界,Quantity of Computers Produced,Quantity of Cars Produce
12、d,3,000,1,000,2,000,2,200,A,700,600,300,0,1,000,B,C,D,Production,possibilities,frontier,电脑产量,汽车产量,生产 可能性边界,Concepts Illustrated by the Production Possibilities Frontier,Efficiency Tradeoffs Opportunity Cost Economic Growth,生产可能性边界阐明的概念,效率 权衡取舍 机会成本 经济增长,The Production Possibilities Frontier,Quantity
13、 of Computers Produced,Quantity of Cars Produced,3,000,2,000,A,700,0,1,000,An outward shift in the production possibilities frontier,生产可能性边界,计算机产量,汽车产量,3,000,2,000,A,700,0,1,000,生产可能性边界 向外移动,Microeconomics and Macroeconomics,Microeconomics focuses on the individual parts of the economy. How househol
14、ds and firms make decisions and how they interact in specific markets Macroeconomics looks at the economy as a whole. How the markets, as a whole, interact at the national level.,微观经济学与宏观经济学,微观经济学 的研究对象是经济中的个体。 家庭和企业如何作出决策，以及他们如何在特定市场上相互交易。 宏观经济学 研究经济总体现象。 从总体上看，各种市场在国家水平上如何相互影响。,Two Roles of Econom
15、ists 经济学家的两个角色,When they are trying to explain the world, they are scientists.当他们努力去解释世界时，他们是科学家。 When they are trying to change the world, they are policymakers.当他们想要改变世界时，他们是政策顾问。,Positive versus Normative Analysis,Positive statements are statements that describe the world as it is. Called descrip
16、tive analysis Normative statements are statements about how the world should be. Called prescriptive analysis,实证分析与规范分析,实证表述 是企图描述世界是什么的观点。 被称为描述性分析。 规范表述 是企图描述世界应该如何运行的观点。 被称为命令性分析。,?,?,Positive or Normative Statements? 实证性还是规范性表述？,An increase in the minimum wage will cause a decrease in employment
17、 among the least-skilled. 提高最低工资水平会导致最低技能工人的就业减少。Positive 实证性,?,?,?,Positive or Normative Statements? 实证性还是规范性表述？,Higher federal budget deficits will cause interest rates to increase. 较高的联邦赤字水平会导致利率上升。Positive 实证性,?,?,?,?,Positive or Normative Statements? 实证性还是规范性表述？,The income gains from a higher m
18、inimum wage are worth more than any slight reductions in employment. 提高最低工资水平得到的利益比由此带来的稍微的就业减少造成的损失大Positive 规范性,?,?,?,Positive or Normative Statements? 实证性还是规范性表述？,State governments should be allowed to collect from tobacco companies the costs of treating smoking-related illnesses among the poor.
19、应该允许州政府向烟草公司收取费用，用于治疗穷人当中与吸烟有关的疾病的费用。Positive 规范性,Economists in Washington . . .,. . . serve as advisers in the policymaking process of the three branches of government: Legislative Executive Judicial,华盛顿的经济学家 . . .,. . .在以下三个政府部门的政策制定过程中充当顾问： 立法 行政 司法,Economists in Washington,Some government agenci
20、es that collect economic data and make economic policy: Department of Commerce http:/merce.gov Bureau of Labor Statistics http:/www.bls.gov Congressional Budget Office http:/www.cbo.gov Federal Reserve Board http:/www.federalreserve.gov,华盛顿的经济学家,一些收集经济数据并制定经济政策的政府部门: 商务部 http:/merce.gov 劳工统计局 http:/
21、www.bls.gov 国会预算办公室 http:/www.cbo.gov 联邦储备委员会 http:/www.federalreserve.gov,Why Economists Disagree 为什么经济学家意见分歧,They may disagree on theories about how the world works.对关于世界如何运行的理论的正确性看法不同。 They may hold different values and, thus, different normative views. 他们可能有不同的价值观，因此就有不同的规范性观点。,Table 2 Ten Prop
22、ositions about Which Most Economists Agree,大多数经济学家一直同意的10个主张 主张以及经济学家同意的百分比,1. 租金上限减少了可得到的住房数量和质量。（93） 2. 关税和进口配额通常降低了普遍的经济福利。（93） 3. 有伸缩性和浮动性的汇率提供了一种有效的国际货币协定。（90） 4. 财政政策 例如，减税和（或）增加政府支出 对低于充分就业的经济有重要的刺激效应。（90） 5. 如果要平衡联邦预算，应该在经济周期中而不是每年中来实现。（85） 6. 现金转移支付使领取者福利的增加大于等量现金的实物转移支付。（84） 7. 巨额联邦预算赤字对经济
23、有不利影响。（83） 8. 最低工资增加了年轻人和不熟练工人中的失业。（79） 9. 政府应该按“负所得税”的思路重建福利制度。（79） 10. 排污税和可交易的污染许可证作为控制污染的方法优于实行污染上限。 （78）,Summary,Economists try to address their subjects with a scientists objectivity. They make appropriate assumptions and build simplified models in order to understand the world around them. Tw
24、o simple economic models are the circular-flow diagram and the production possibilities frontier.,小结,经济学家像科学家一样客观地来研究他们的学科。 为了理解周围的世界，经济学家进行适当的假设并建立简单的模型。 两个简单的经济模型是经济循环图和生产可能性边界。,Summary,The field of economics is divided into two subfields: microeconomics and macroeconomics. Microeconomists study d
25、ecisionmaking by households and firms in the marketplace.Macroeconomists study the forces and trends that affect the economy as a whole.,小结,经济学分为两个领域：微观经济学和宏观经济学。 微观经济学家研究市场中的家庭和企业所作的决策。 宏观经济学家研究影响整体经济的力量和趋势。,Summary,Economics relies on both positive and normative analysis. Positive statements is an
26、 assertion about how the world “is”。 normative statements is an assertion about how the world “ought to be”. When economists make normative statements, they are acting more as policy advisors than scientists.,小结,经济学依赖实证分析和规范分析。 实证表述是关于世界是什么的论断。 规范表述是关于世界应该是什么的论断。 当经济学家做规范性表述时，与其说其是科学家，不如说其是政策顾问。,Sum
27、mary,Economists who advise policymakers may offer conflicting advice either because of differences in scientific judgments or because of differences in values At other times, economists are united in the advice they offer, but policymakers may choose to ignore it.,小结,给政策制定者提供建议的经济学家提出相互冲突的建议，这是因为科学判
28、断的不同，或者是价值观的不同。 在其他一些时候，经济学家在他们提供的建议上相互一直，但是政策制订者可能选择不采纳。,Government (41%),Other (4%),Individuals (23%),Private Insurers (32%),(a) Pie Chart,Productivity Index (farm,output per hour of labor,1977 = 100),100,80,60,40,20,0,160,120,140,(c) Time-Series Graph,1950,1960,1970,1980,1990,1996 Value (in,billi
29、ons of dollars),General,Electric,($126 billion),100,80,60,40,20,0,120,$140,Exxon,($99 billion),(b) Bar Graph,IBM,($68 billion),General,Motors,($39 billion),Figure 2A-1,Grade,Point,Average,2.5,2.0,1.5,1.0,0.5,40,Study,Time,(hours per week),3.0,3.5,4.0,0,5,10,15,20,25,30,35,Alfred E.,(5, 2.0),Albert E
30、.,(25, 3.5),Figure 2A-2,Price of,Novels,5,4,3,2,1,30,Quantity,of Novels,Purchased,6,7,8,9,10,$11,0,5,10,15,20,25,Demand,D,1,(5, $10),(9, $9),(13, $8),(17, $7),(21, $6),(25, $5),Figure 2A-3,Price of,Novels,5,4,3,2,1,30,Quantity,of Novels,Purchased,6,7,8,9,10,$11,0,5,13,16,10,15,20,25,(13, $8),(16, $8
31、),D,3,(income =,$20,000),D,1,(income =,$30,000),D,2,(income =,$40,000),(10, $8),When income increases,the demand curve,shifts to the right.,When income,decreases, the,demand curve,shifts to the left.,Figure 2A-4,Price of,Novels,5,4,3,2,1,30,Quantity,of Novels,Purchased,6,7,8,9,10,$11,0,5,21,13,10,15,20,25,Demand,D,1,(13, $8),(21, $6),6,2,8,5,2,2,21,2,13,5,8,Figure 2A-5,Figure 2A-6,Violent,Crimes,(per 1,000,people),Police Officers,(per 1,000 people),0,Figure 2A-7,
