(精品)经济学原理第2章.ppt

《(精品)经济学原理第2章.ppt》由会员分享，可在线阅读，更多相关《(精品)经济学原理第2章.ppt（81页珍藏版）》请在淘文阁 - 分享文档赚钱的网站上搜索。

1、 2009 South-Western,a part of Cengage Learning,all rights reservedC H A P T E RThinking Like An EconomistEconomicsP R I N C I P L E S O FP R I N C I P L E S O FN.Gregory MankiwPremium PowerPoint Slides by Ron Cronovich2In this chapter,look for the answers to these questions:What are economists two r

2、oles?How do they differ?What are models?How do economists use them?What are the elements of the Circular-Flow Diagram?What concepts does the diagram illustrate?How is the Production Possibilities Frontier related to opportunity cost?What other concepts does it illustrate?What is the difference betwe

3、en microeconomics and macroeconomics?Between positive and normative?1THINKING LIKE AN ECONOMIST2The Economist as ScientistEconomists play two roles:1.Scientists:try to explain the world2.Policy advisors:try to improve itIn the first,economists employ the scientific method,the dispassionate developme

4、nt and testing of theories about how the world works.THINKING LIKE AN ECONOMIST3Assumptions&ModelsAssumptions simplify the complex world,make it easier to understand.Example:To study international trade,assume two countries and two goods.Unrealistic,but simple to learn and gives useful insights abou

5、t the real world.Model:a highly simplified representation of a more complicated reality.Economists use models to study economic issues.THINKING LIKE AN ECONOMIST4Some Familiar ModelsA road mapTHINKING LIKE AN ECONOMIST5Some Familiar ModelsA model of human anatomy from high school biology classTHINKI

6、NG LIKE AN ECONOMIST6Some Familiar ModelsA model airplaneTHINKING LIKE AN ECONOMIST7Some Familiar ModelsThe model teeth at the dentists officeDont forget to floss!THINKING LIKE AN ECONOMIST8Our First Model:The Circular-Flow DiagramThe Circular-Flow Diagram:a visual model of the economy,shows how dol

7、lars flow through markets among households and firmsTwo types of“actors”:householdsfirms Two markets:the market for goods and services the market for“factors of production”THINKING LIKE AN ECONOMIST9Factors of ProductionFactors of production:the resources the economy uses to produce goods&services,i

8、ncludinglabor land capital(buildings&machines used in production)THINKING LIKE AN ECONOMIST10FIGURE 1:The Circular-Flow DiagramHouseholds:Own the factors of production,sell/rent them to firms for incomeBuy and consume goods&servicesHouseholdsFirmsFirms:Buy/hire factors of production,use them to prod

9、uce goods and servicesSell goods&servicesTHINKING LIKE AN ECONOMIST11FIGURE 1:The Circular-Flow DiagramMarkets for Factors of ProductionHouseholdsFirms IncomeWages,rent,profitFactors of productionLabor,land,capital SpendingG&S boughtG&S soldRevenueMarkets for Goods&ServicesTHINKING LIKE AN ECONOMIST

10、12Our Second Model:The Production Possibilities FrontierThe Production Possibilities Frontier(PPF):a graph that shows the combinations of two goods the economy can possibly produce given the available resources and the available technology Example:Two goods:computers and wheatOne resource:labor(meas

11、ured in hours)Economy has 50,000 labor hours per month available for production.PPF ExampleProducing one computer requires 100 hours labor.Producing one ton of wheat requires 10 hours labor.5,00004,0001002,5002501,00040050,000040,00010,00025,00025,00010,00040,0000500050,000EDCBAWheatComputersWheatCo

12、mputersProductionEmployment of labor hoursTHINKING LIKE AN ECONOMIST14Point on graphProductionCom-putersWheatA5000B4001,000C2502,500D1004,000E05,000ABCDEPPF ExampleA.On the graph,find the point that represents(100 computers,3000 tons of wheat),label it F.Would it be possible for the economy to produ

13、ce this combination of the two goods?Why or why not?B.Next,find the point that represents(300 computers,3500 tons of wheat),label it G.Would it be possible for the economy to produce this combination of the two goods?A C T I V E L E A R N I N G A C T I V E L E A R N I N G 1 1 Points off the PPF15A C

14、 T I V E L E A R N I N G A C T I V E L E A R N I N G 1 1 Answers16Point F:100 computers,3000 tons wheatPoint F requires 40,000 hours of labor.Possible but not efficient:could get more of either good w/o sacrificing any of the other.FA C T I V E L E A R N I N G A C T I V E L E A R N I N G 1 1 Answers

15、17Point G:300 computers,3500 tons wheatPoint G requires 65,000 hours of labor.Not possible because economy only has 50,000 hours.GTHINKING LIKE AN ECONOMIST18The PPF:What We Know So FarPoints on the PPF(like A E)possibleefficient:all resources are fully utilizedPoints under the PPF(like F)possibleno

16、t efficient:some resources underutilized(e.g.,workers unemployed,factories idle)Points above the PPF(like G)not possibleTHINKING LIKE AN ECONOMIST19The PPF and Opportunity CostRecall:The opportunity cost of an item is what must be given up to obtain that item.Moving along a PPF involves shifting res

17、ources(e.g.,labor)from the production of one good to the other.Society faces a tradeoff:Getting more of one good requires sacrificing some of the other.The slope of the PPF tells you the opportunity cost of one good in terms of the other.THINKING LIKE AN ECONOMIST20The PPF and Opportunity CostThe sl

18、ope of a line equals the“rise over the run,”the amount the line rises when you move to the right by one unit.1000100slope=10Here,the opportunity cost of a computer is 10 tons of wheat.A C T I V E L E A R N I N G A C T I V E L E A R N I N G 2 2 PPF and Opportunity Cost21In which country is the opport

19、unity cost of cloth lower?FRANCEENGLANDA C T I V E L E A R N I N G A C T I V E L E A R N I N G 2 2 Answers22FRANCEENGLANDEngland,because its PPF is not as steep as Frances.THINKING LIKE AN ECONOMIST23Economic Growth and the PPFWith additional resources or an improvement in technology,the economy can

20、 produce more computers,more wheat,or any combination in between.Economic growth shifts the PPF outward.THINKING LIKE AN ECONOMIST24The Shape of the PPFThe PPF could be a straight line,or bow-shapedDepends on what happens to opportunity cost as economy shifts resources from one industry to the other

21、.If opp.cost remains constant,PPF is a straight line.(In the previous example,opp.cost of a computer was always 10 tons of wheat.)If opp.cost of a good rises as the economy produces more of the good,PPF is bow-shaped.THINKING LIKE AN ECONOMIST25Why the PPF Might Be Bow-ShapedMountain BikesBeerAs the

22、 economy shifts resources from beer to mountain bikes:PPF becomes steeperopp.cost of mountain bikes increases THINKING LIKE AN ECONOMIST26AWhy the PPF Might Be Bow-ShapedAt point A,most workers are producing beer,even those that are better suited to building bikes.So,do not have to give up much beer

23、 to get more bikes.Mountain BikesBeerAt A,opp.cost of mtn bikes is low.THINKING LIKE AN ECONOMIST27BWhy the PPF Might Be Bow-ShapedAt B,most workers are producing bikes.The few left in beer are the best brewers.Producing more bikes would require shifting some of the best brewers away from beer produ

24、ction,would cause a big drop in beer output.Mountain BikesBeerAt B,opp.cost of mtn bikes is high.THINKING LIKE AN ECONOMIST28Why the PPF Might Be Bow-ShapedSo,PPF is bow-shaped when different workers have different skills,different opportunity costs of producing one good in terms of the other.The PP

25、F would also be bow-shaped when there is some other resource,or mix of resources with varying opportunity costs(E.g.,different types of land suited for different uses).THINKING LIKE AN ECONOMIST29The PPF:A SummaryThe PPF shows all combinations of two goods that an economy can possibly produce,given

26、its resources and technology.The PPF illustrates the concepts of tradeoff and opportunity cost,efficiency and inefficiency,unemployment,and economic growth.A bow-shaped PPF illustrates the concept of increasing opportunity cost.THINKING LIKE AN ECONOMIST30Microeconomics and MacroeconomicsMicroeconom

27、ics is the study of how households and firms make decisions and how they interact in markets.Macroeconomics is the study of economy-wide phenomena,including inflation,unemployment,and economic growth.These two branches of economics are closely intertwined,yet distinct they address different question

28、s.The Economist as Policy AdvisorAs scientists,economists make positive statements,which attempt to describe the world as it is.As policy advisors,economists make normative statements,which attempt to prescribe how the world should be.Positive statements can be confirmed or refuted,normative stateme

29、nts cannot.Govt employs many economists for policy advice.E.g.,the U.S.President has a Council of Economic Advisors,which the author of this textbook chaired from 2003 to 2005.31A C T I V E L E A R N I N G A C T I V E L E A R N I N G 3 3 Identifying positive vs.normative32Which of these statements a

30、re“positive”and which are“normative”?How can you tell the difference?a.Prices rise when the government increases the quantity of money.b.The government should print less money.c.A tax cut is needed to stimulate the economy.d.An increase in the price of burritos will cause an increase in consumer dem

31、and for video rentals.A C T I V E L E A R N I N G A C T I V E L E A R N I N G 3 3 Answers33a.Prices rise when the government increases the quantity of money.Positive describes a relationship,could use data to confirm or refute.b.The government should print less money.Normative this is a value judgme

32、nt,cannot be confirmed or refuted.A C T I V E L E A R N I N G A C T I V E L E A R N I N G 3 3 Answers34c.A tax cut is needed to stimulate the economy.Normative another value judgment.d.An increase in the price of burritos will cause an increase in consumer demand for video rentals.Positive describes

33、 a relationship.Note that a statement need not be true to be positive.THINKING LIKE AN ECONOMIST35Why Economists DisagreeEconomists often give conflicting policy advice.They sometimes disagree about the validity of alternative positive theories about the world.They may have different values and,ther

34、efore,different normative views about what policy should try to accomplish.Yet,there are many propositions about which most economists agree.THINKING LIKE AN ECONOMIST36Propositions about Which Most Economists Agree (and%who agree)A ceiling on rents reduces the quantity and quality of housing availa

35、ble.(93%)Tariffs and import quotas usually reduce general economic welfare.(93%)The United States should not restrict employers from outsourcing work to foreign countries.(90%)The United States should eliminate agriculture subsidies.(85%)continuedTHINKING LIKE AN ECONOMIST37Propositions about Which

36、Most Economists Agree (and%agreeing)The gap between Social Security funds and expenditures will become unsustainably large within the next fifty years if current policies remain unchanged.(85%)A large federal budget deficit has an adverse effect on the economy.(83%)A minimum wage increases unemploym

37、ent among young and unskilled workers.(79%)Effluent taxes and marketable pollution permits represent a better approach to pollution control than imposition of pollution ceilings.(78%)FYI:Who Studies Economics?(in college)Ronald Reagan,President of the United StatesBarbara Boxer,U.S.Senator Sandra Da

38、y-OConnor,Former Supreme Court JusticeAnthony Zinni,Former General,U.S.Marine Corps Kofi Annan,Former Secretary General,United NationsMeg Witman,Chief Executive Officer,eBaySteve Ballmer,Chief Executive Officer,MicrosoftArnold Schwarzenegger,Governor of California,ActorBen Stein,Political Speechwrit

39、er,Actor,Game Show HostMick Jagger,Singer for the Rolling Stones John Elway,NFL QuarterbackTiger Woods,GolferDiane von Furstenburg,Fashion Designer38CHAPTER SUMMARYAs scientists,economists try to explain the world using models with appropriate assumptions.Two simple models are the Circular-Flow Diag

40、ram and the Production Possibilities Frontier.Microeconomics studies the behavior of consumers and firms,and their interactions in markets.Macroeconomics studies the economy as a whole.As policy advisers,economists offer advice on how to improve the world.39 2009 South-Western,a part of Cengage Lear

41、ning,all rights reservedC H A P T E R像经济学家一样思考像经济学家一样思考经济学原理N.N.格里高利格里高利.曼昆曼昆 著著Premium PowerPoint Slides by Ron Cronovich2像经济学家一样思考41本教学PPT双语版由浙江工商大学经济学院 陈宇峰 编译41本章将探索这些问题的答案：本章将探索这些问题的答案：经济学家的两种角色是什么？它们有什么不同？什么是模型？经济学家怎么使用它们？循环流量图的构成要素有哪些？流量图想要说明什么问题？生产可能性边界与机会成本有什么联系？它还表示了什么其他概念？微观经济学与宏观经济学有什么不同？

42、实证经济学与规范经济学呢？42像经济学家一样思考43作为科学家的经济学家作为科学家的经济学家经济学家扮演的两种角色：1.科学家：试图解释世界 2.政策顾问：尝试改善世界作为科学家，经济学家使用科学方法冷静地建立并检验有关世界如何运行的各种理论像经济学家一样思考44假设与模型假设与模型假设可以简化复杂的世界，使之更容易理解比如：为了研究国际贸易，假设世界上只由两个国家组成，而且每个国家只生产两种产品。尽管在实际中是不真实的，但这可以帮助我们更方便的学习和理解现实世界模型：模型：一个复杂现象的高度简化 经济学家使用模型来研究经济问题像经济学家一样思考45常用的模型常用的模型地图像经济学家一样思考4

43、6熟悉的模型熟悉的模型高中生物课堂上的人体解剖模型像经济学家一样思考47熟悉的模型熟悉的模型飞机模型像经济学家一样思考48熟悉的模型熟悉的模型牙医办公室的牙齿模型不要忘了刷牙!像经济学家一样思考49我们的第一个模型：循环流量图我们的第一个模型：循环流量图循环流量图：一个说明货币如何通过市场在家庭与企业之间流动的直观经济模型两类主体：家庭企业两个市场：物品与劳务市场生产要素市场像经济学家一样思考50生产要素生产要素生产要素：生产要素：经济体用来生产物品与劳务的资源，经济体用来生产物品与劳务的资源，包括：包括：劳动土地 资本（建筑物和用于生产的机器）像经济学家一样思考51图图1：循环流量图：循环流

44、量图家庭家庭:拥有并出售或出租生产要素给企业以获得收入购买并消费物品与劳务家庭企业企业：购买或雇佣生产要素并用以生产物品与劳务出售物品与劳务像经济学家一样思考52图图1：循环流量图：循环流量图生产要素市场家庭企业收入工资，租金与利润生产要素劳动，土地和资本 支出物品与劳务购买物品与劳务出售收益物品与劳务市场像经济学家一样思考53我们的第二个模型：生产可能性边界我们的第二个模型：生产可能性边界生产可能性边界（PPF）：表示在可得到的生产要素与生产技术既定时，一个经济所能生产的两种产品数量的各种组合的图形例如：两种物品：电脑与小麦一种资源：劳动力（以小时为单位来衡量）每月经济有50，000个劳动小

45、时可用于生产生产可能性边界的例子生产可能性边界的例子生产一台电脑需要100个小时的劳动生产一吨小麦需要10个小时的劳动5,00004,0001002,5002501,00040050,000040,00010,00025,00025,00010,00040,0000500050,000EDCBA小麦电脑小麦电脑生产雇佣的劳动小时像经济学家一样思考55图表上点生产电脑小麦A5000B4001,000C2502,500D1004,000E05,000ABCDE生产可能性边界的例子生产可能性边界的例子A.在图上找出代表（100台电脑，3000吨小麦）的点，并标作F。经济能生产出这样的两种产品数量组合

46、吗？为什么？B.接下来，找出代表（300台电脑，3500吨小麦）的点，并标作G。经济能生产出这样的两种产品组合吗？为什么？主动学习主动学习 1 不在生产可能性边界上的点不在生产可能性边界上的点56主动学习主动学习 1 1 参考答案参考答案57点 F:100台电脑,3000吨小麦点 F 需要40,000个小时的劳动。能够但没有效率：不用减少任何物品的生产便能获得更多的两种物品F主动学习主动学习 1 1 参考答案参考答案58点 G:300 台电脑,3500 吨小麦点G需要65，000个小时的劳动，因为经济只有50，000个劳动小时，所以不可能。G像经济学家一样思考59 关于生产可能性边界目前为止我

47、们所知的内容关于生产可能性边界目前为止我们所知的内容在生产可能性边界上的点（A-E)能够达到有效率：所以资源都已经充分利用在生产可能性边界以内的点（F）能够达到没有效率：一些资源没有充分利用（比如，工人失业，厂房闲置等）在生产可能性边界以外的点（G）不能达到像经济学家一样思考60生产可能性边界与机会成本生产可能性边界与机会成本复习：机会成本是为了得到某种东西所必须放弃的东西沿着生产可能性边界移动意味着将资源（比如劳动）从一种物品的生产转移到另一种物品的生产中社会面临权衡取舍：得到更多的一种物品需要以更少的另一种物品为代价生产可能性边界的斜率告诉我们以一种物品来衡量另一种物品的机会成本像经济学家

48、一样思考61生产可能性边界与机会成本生产可能性边界与机会成本直线的斜率等于直线的横坐标向右移动一个单位时，直线的纵坐标变化的大小1000100斜率=10本图，1台电脑的机会成本是10吨小麦主动学习主动学习 2 2 生产可能性边界与机会成本生产可能性边界与机会成本62在哪个国家布料的机会成本更小？法国法国英格兰英格兰主动学习主动学习 2 2 参考答案参考答案63法国法国英格兰英格兰 英格兰，因为它的生产可能性边界的斜率没有法国的陡峭像经济学家一样思考64经济增长和生产可能性边界经济增长和生产可能性边界如果有额外的资源或技术进步，经济便能生产更多的电脑，小麦，或两种物品的组合.经济增长使生产可能性

49、边界向外移动像经济学家一样思考65生产可能性边界的形状生产可能性边界的形状生产可能性边界可以是直线或曲线取决于经济将资源从一个行业转向另一个行业时机会成本的变化情况如果机会成本不变，那生产可能性边界为一条直线（在上述例子中，1台电脑的机会成本恒为10吨小麦）如果一种物品的机会成本随着生产数量的增多而上升，那生产可能性边界为曲线像经济学家一样思考66为什么生产可能性边界可能是曲线为什么生产可能性边界可能是曲线山地自行车山地自行车啤酒啤酒当经济把资源从啤酒行业向山地自行车行业转移时：生产可能性边界变得更加陡峭山地自行车的机会成本也不断上升像经济学家一样思考67A为什么生产可能性边界可能是曲线为什么

50、生产可能性边界可能是曲线在点A，大部分工人都在生产啤酒，即使这些工人更加适合于生产山地自行车。因此，为得到更多的自行车无需放弃太多啤酒山地自行车山地自行车啤酒啤酒在点A,山地自行车的机会成本很小像经济学家一样思考68B为什么生产可行性边界可能是曲线为什么生产可行性边界可能是曲线在点B,大部分工人都在生产自行车，留在啤酒行业的工人是最好的酿酒师。生产更多的自行车需要将最好的酿酒师从啤酒行业转移出来，这会使啤酒产量大幅度降低山地自行车山地自行车啤酒啤酒在点B,山地自行车的机会成本很高像经济学家一样思考69为什么生产可能性边界可能是曲线为什么生产可能性边界可能是曲线因此，当不同的工人有不同的技能，多