曼昆经济学原理微观部分第6章课件.ppt

,Supply,Demand,and Government Policies,In a free,unregulated market system,market forces establish equilibrium prices and exchange quantities.While equilibrium conditions may be efficient,it may be true that not everyone is satisfied.One of the roles of economists is to use their theories to assist in the development of policies.,供给、需求与政府政策,在一个自由、无管制的市场系统中，市场力量实现均衡价格和均衡交易量。这种均衡结果也许是有效的，但并不是每个人对此都感到满意。经济学家的作用之一就是利用他们的理论帮助制定政策。,Controls on Price.价格控制,Are usually enacted when policymakers believe the market price is unfair to buyers or sellers.当政策制定者认为市场价格对买者或卖者不公平时，往往实行价格控制。Result in government-created price ceilings and floors.这就促使政府实行价格上限和价格下限政策。,Controls on Price.价格控制,Price Ceiling 价格上限A legally established maximum price at which a good can be sold.可以出售一种物品的法定最高价格。Price Floor 价格下限 A legally established minimum price at which a good can be sold.可以出售一种物品的法定最低价格。,How Price Ceilings Affect Market Outcomes,Two outcomes are possible when the government imposes a price ceiling:The price ceiling is not binding if set above the equilibrium price.The price ceiling is binding if set below the equilibrium price,leading to a shortage.,价格上限如何影响市场结果,当政府实行价格上限时，可能出现两种价格：如果价格上限高于均衡 价格，价格上限没有限制作用。如果价格上限低于均衡 价格，价格上限对市场有限制作用。,A Price Ceiling That Is Not Binding.,$4,3,Quantity ofIce-CreamCones,0,Price ofIce-CreamCone,Demand,Supply,100,Equilibriumquantity,没有限制作用的价格上限.,$4,3,冰激凌蛋卷的数量,0,冰激凌蛋卷的价格,需求,供给,100,均衡数量,A Price Ceiling That Is Binding.,$3,Quantity ofIce-CreamCones,0,Price ofIce-CreamCone,2,Demand,Supply,有限制作用的价格上限.,$3,冰激凌蛋卷的数量,0,冰激凌蛋卷的价格,2,需求,供给,How Price Ceilings Affect Market Outcomes,Effects of Price CeilingsA binding price ceiling creates.shortages because QD QS.Example:Gasoline shortage of the 1970s nonprice rationingExamples:Long lines,Discrimination by sellers,价格上限如何影响市场结果,价格上限的作用有限制作用的价格上限造成.短缺，因为 QD QS.例子:70年代的汽油短缺 非市场价格方式配给例子:排长队,卖者歧视,Lines at the Gas Pump,In 1973 OPEC raised the price of crude oil in world markets.Because crude oil is the major input used to make gasoline,the higher oil prices reduced the supply of gasoline.,What was responsible for the long gas lines?,Economists blame government regulations that limited the price oil companies could charge for gasoline.,加油站前的长队,1973年，石油输出国组织（OPEC)提高了世界石油市场的原油价格。由于原油是用于生产汽油的主要投入，较高石油价格减少了汽油供给。,谁对加油站前的长队负责？,经济学家把它归咎于限制石油公司对汽油可以收取的价格的政府管制。,The Price Ceiling on Gasoline Is Not Binding.汽油的价格上限没有限制性,$4,P1,Quantity of Gasoline汽油数量,0,Price of Gasoline汽油价格,Q1,Demand 需求,Supply 供给,The Price Ceiling on Gasoline Is Binding.,P1,Quantity ofGasoline,0,Price ofGasoline,Q1,Demand,S1,Priceceiling,汽油的价格上限有限制性.,P1,汽油数量,0,汽油价格,Q1,需求,S1,价格上限,Rent Control in the Short Run and Long Run,Rent controls are ceilings placed on the rents that landlords may charge their tenants.The goal of rent control policy is to help the poor by making housing more affordable.One economist called rent control“the best way to destroy a city,other than bombing.”,短期中和长期中的租金控制,租金控制房东能向房客收取的租金上限。这一政策的目的是帮助穷人更能租得起住房。一位经济学家称租金控制是“除了轰炸之外毁灭一个城市的最好方法”。,Rent Control in the Short Run.,Quantity ofApartments,0,Rental Price ofApartment,Demand,Supply,Supply and demand for apartments are relatively inelastic,短期的租金控制.,公寓数量,0,公寓租金价格,需求,供给,供给与需求都相对缺乏弹性,Rent Control in the Long Run.,Quantity ofApartments,0,Rental Price ofApartment,Demand,Supply,Because the supply and demand for apartments are more elastic.,rent control causes a large shortage,长期的租金控制.,公寓数量,0,公寓租金价格,需求,供给,因为供给和需求更富有弹性,租金控制导致大量短缺,How Price Floors Affect Market Outcomes,When the government imposes a price floor,two outcomes are possible.The price floor is not binding if set below the equilibrium price.The price floor is binding if set above the equilibrium price,leading to a surplus.,价格下限如何影响市场结果,当政府实行价格下限时，可能出现两种价格：如果价格下限低于均衡价格，价格下限没有限制作用。如果价格下限高于均衡价格，价格下限对市场有限制作用，导致过剩。,A Price Floor That Is Not Binding.,$3,Quantity ofIce-CreamCones,0,Price ofIce-CreamCone,100,Equilibriumquantity,Demand,Supply,2,没有限制性的价格下限.,$3,冰激凌蛋卷的数量,0,冰激凌蛋卷的价格,100,均衡数量,需求,供给,2,A Price Floor That Is Binding.,$3,Quantity ofIce-CreamCones,0,Price ofIce-CreamCone,Demand,Supply,$4,有限制性的价格下限.,$3,冰激凌蛋卷的数量,0,冰激凌蛋卷的价格,需求,供给,$4,How Price Floors Affect Market Outcomes 价格下限如何影响市场结果,A price floor prevents supply and demand from moving toward the equilibrium price and quantity.价格下限阻止供给和需求调整到均衡价格和均衡数量When the market price hits the floor,it can fall no further,and the market price equals the floor price.当市场价格达到下限时，它就不能再下降，此时市场价格等于下限价格。,How Price Floors Affect Market Outcomes,A binding price floor causes.a surplus because QS QD.nonprice rationing is an alternative mechanism for rationing the good,using discrimination criteria.Examples:The minimum wage,Agricultural price supports,价格下限如何影响市场结果,有限制作用的价格下限导致.过剩，因为 QS QD.非价格方式配给是根据歧视来配给物品的一种方式。例子:最低工资,对农产品价格的支持。,The Minimum Wage 最低工资,An important example of a price floor is the minimum wage.Minimum wage laws dictate the lowest price possible for labor that any employer may pay.价格下限的一个重要例子是最低 工资。最低工资法规定了任何一 个雇主要支付的最低劳动工资价格,The Minimum Wage 最低工资,Quantity of Labor劳动量,0,Wage工资,Labor demand劳动需求,Labor supply劳动供给,A Free Labor Market自由市场,How the Minimum Wage Affects the Labor Market,Quantity ofLabor,0,Wage,Labor demand,Labor supply,A Labor Market with a Minimum Wage,最低工资如何影响劳动市场,劳动量,0,工资,劳动需求,劳动供给,有限制性最低工资的劳动市场,Taxes 税收,Governments levy taxes to raise revenue for public projects.政府利用税收为公共项目筹资,How Taxes on Buyers(and Sellers)Affect Market Outcomes,Taxes discourage market activity.When a good is taxed,the quantity sold is smaller.Buyers and sellers share the tax burden.,对买者和卖者收税如何影响市场结果,税收抑制了市场活动。当一种物品被征税时，它的销售量减少。买者和卖者分摊税收负担。,Elasticity and Tax Incidence,Tax incidence is the study of who bears the burden of a tax.Taxes result in a change in market equilibrium.Buyers pay more and sellers receive less,regardless of whom the tax is levied on.,弹性与税收归宿,税收归宿 关于由谁承担税收负担的研究。税收导致市场均衡的变动。不管向谁收税，买者支付的价格更高，卖者收到的价格更低。,Impact of a 50 Tax Levied on Buyers.,3.00,Quantity ofIce-Cream Cones,0,Price ofIce-CreamCone,100,D1,Supply,S1,向买者征收0.5美元税收的影响,3.00,冰激凌蛋卷的数量,0,冰激凌蛋卷的价格,100,D1,供给,S1,3.00,Quantity ofIce-Cream Cones,0,Price ofIce-CreamCone,100,90,D1,D2,Supply,S1,Impact of a 50 Tax Levied on Buyers.,3.00,冰激凌蛋卷的数量,0,冰激凌蛋卷的价格,100,90,D1,D2,供给,S1,向买者征收0.5美元税收的影响,What was the impact of tax?,Taxes discourage market activity.When a good is taxed,the quantity sold is smaller.Buyers and sellers share the tax burden.,税收的潜在影响是什么?,税收抑制了市场活动。当一种物品被征税时，它的销售量减少。买者和卖者分摊税收负担。,3.00,0,100,S1,Demand,D1,Impact of a 50 Tax on Sellers.,3.00,0,100,S1,需求,D1,向卖者征收0.5美元税收的影响,A Payroll Tax,Quantity ofLabor,0,Wage,Labor demand,Labor supply,工薪税,劳动量,0,工资,劳动需求,劳动供给,Elasticity and Tax Incidence,In what proportions is the burden of the tax divided?How do the effects of taxes on sellers compare to those levied on buyers?,The answers to these questions depend on the elasticity of demand and the elasticity of supply.,弹性与税收归宿,税收负担是按什么比例分摊的？怎样比较向买者征税与向卖者征税的结果？,这些问题的答案取决于需求弹性 和供给弹性。,（a）Elastic Supply,Inelastic Demand.,Quantity,0,Price,Demand,Supply,Figure 9 How the Burden of a Tax Is Divided,（a）供给富有弹性，需求缺乏弹性.,数量,0,价格,需求,供给,图9.税收负担如何分摊的,(b)Inelastic Supply,Elastic Demand.,Quantity,0,Price,Demand,Supply,Figure 9 How the Burden of a Tax Is Divided,(b)供给缺乏弹性，需求富有弹性.,数量,0,价格,需求,供给,图9.税收负担如何分摊的,So,how is the burden of the tax divided?,The burden of a tax falls more heavily on the side of the market that is less elastic.,ELASTICITY AND TAX INCIDENCE,所以,税收负担是如何分摊的?,税收负担更多地落在缺乏弹性的市场一方身上。,弹性与税收归宿,Summary,Price controls include price ceilings and price floors.A price ceiling is a legal maximum on the price of a good or service.An example is rent control.A price floor is a legal minimum on the price of a good or a service.An example is the minimum wage.,小结,价格控制包括价格上限和价格下限。价格上限是某种物品或劳务价格法定的最高限。租金控制是一个例子。价格下限是某种物品或劳务价格法定的最低限。最低工资是一个例子。,Summary,Taxes are used to raise revenue for public purposes.When the government levies a tax on a good,the equilibrium quantity of the good falls.A tax on a good places a wedge between the price paid by buyers and the price received by sellers.,小结,税收是用来为公共目的筹资的。当政府对一种物品征税时，该物品的均衡数量减少。对一种物品征税是在买者支付的价格与卖者得到的价格之间打入了一个楔子。,Summary,The incidence of a tax refers to who bears the burden of a tax.The incidence of a tax does not depend on whether the tax is levied on buyers or sellers.The incidence of the tax depends on the price elasticities of supply and demand.The burden tends to fall on the side of the market that is less elastic.,小结,税收归宿是指谁承担了税收负担。税收归宿不取决于是向买者征税，还是向卖者征税。税收归宿取决于供给和需求的价格弹性。税收负担倾向于落在缺乏弹性的市场一方身上。,