《市场如何运行》PPT课件.ppt

,2SUPPLYANDDEMANDI:HOWMARKETSWORK供给与需求（I）：市场如何运行,TheMarketForcesofSupplyandDemand供给与需求的市场力量,Chapter4,TheMarketForcesofSupplyandDemand,Supplyanddemandarethetwowordsthateconomistsusemostoften.Supplyanddemandaretheforcesthatmakemarketeconomieswork.Modernmicroeconomicsisaboutsupply,demand,andmarketequilibrium.,供给与需求的市场力量,供给和需求是经济学家最常用的两个词。供给和需求是让市场经济运行的力量。现代微观经济学就是关于供给、需求和市场均衡的学科。,Markets,Amarketisagroupofbuyersandsellersofaparticulargoodorservice.Thetermssupplyanddemandrefertothebehaviorofpeople.astheyinteractwithoneanotherinmarkets.,市场,市场是指某种物品或劳务的一群买者与卖者的集合。供给与需求这两个术语是指人们在市场上相互交易时的行为。,Marketsandcompetition市场与竞争,Buyersdeterminedemand.买者决定需求,Sellersdeterminesupply.卖者决定供给,ACompetitiveMarket竞争市场,Acompetitivemarketisamarketinwhichtherearemanybuyersandsellerssothateachhasanegligibleimpactonthemarketprice竞争市场有很多买者和卖者的市场，所以每一个买者或卖者对市场价格的影响都可以忽略不计。,Competition:PerfectandOtherwise,ProductsarethesameNumerousbuyersandsellerssothateachhasnoinfluenceoverpriceBuyersandSellersarepricetakers,PerfectCompetition,竞争:完全及其它,产品是完全相同的。买者和卖者如此之多，以至于没有一个买者或卖者可以影响价格。买者和卖者都是价格接受者。,完全竞争,Competition:PerfectandOtherwise,MonopolyOneseller,andsellercontrolspriceOligopolyFewsellersNotalwaysaggressivecompetition,竞争:完全及其它,垄断一个卖者，卖者决定价格。寡头少数几个卖者。并不总是主动地进行竞争。,Competition:PerfectandOtherwise,MonopolisticCompetitionManysellersSlightlydifferentiatedproductsEachsellermaysetpriceforitsownproduct,竞争:完全及其它,垄断竞争许多卖者略有差异的产品每个卖者都有决定自己产品价格的能力,Demand需求,Quantitydemandedistheamountofagoodthatbuyersarewillingandabletopurchase.需求量是指买者愿意而且能够购买的一种物品或劳务的数量。,LawofDemand需求规律,Thelawofdemandstatesthatthereisaninverserelationshipbetweenpriceandquantitydemanded.需求规律认为，价格与需求量之间的关系是负关系。,DemandSchedule需求表,Thedemandscheduleisatablethatshowstherelationshipbetweenthepriceofthegoodandthequantitydemanded.需求表表示一种物品的价格与需求量之间关系的表格。,CatherinesDemandSchedule凯瑟琳的需求表,DemandCurve需求曲线,Thedemandcurveisthedownward-slopinglinerelatingpricetoquantitydemanded.需求曲线把价格与需求量联系在一起的向右下方倾斜的曲线。,Figure1CatherinesDemandScheduleandDemandCurve,Priceof,Ice-CreamCone,0,2.50,2.00,1.50,1.00,0.50,1,2,3,4,5,6,7,8,9,10,11,Quantityof,Ice-CreamCones,$3.00,12,图1.Catherine的需求表和需求曲线,冰激凌蛋卷的价格,0,2.50,2.00,1.50,1.00,0.50,1,2,3,4,5,6,7,8,9,10,11,冰激凌蛋卷需求量,$3.00,12,MarketDemandversusIndividualDemand,Marketdemandreferstothesumofallindividualdemandsforaparticulargoodorservice.Graphically,individualdemandcurvesaresummedhorizontallytoobtainthemarketdemandcurve.,市场需求,市场需求是指所有个人对某种物品或劳务需求的总和。从图形上看,把个人需求曲线水平相加，就得出了市场需求曲线。,ChangeinQuantityDemandedversusChangeinDemand,ChangeinQuantityDemandedMovementalongthedemandcurve.Causedbyachangeinthepriceoftheproduct.,需求量的变化与需求的变化,需求量的变化沿着需求曲线移动。是由于产品价格变动引起的。,0,D,PriceofIce-CreamCones,QuantityofIce-CreamCones,Ataxthatraisesthepriceofice-creamconesresultsinamovementalongthedemandcurve.,A,8,1.00,ChangesinQuantityDemanded,0,D,冰激凌蛋卷的价格,冰激凌蛋卷的消费量,提高冰激凌蛋卷价格的税收引起沿着需求曲线的移动,A,8,1.00,需求量的变化,ShiftsintheDemandCurve,ConsumerincomePricesofrelatedgoodsTastesExpectationsNumberofbuyers,需求曲线的移动,消费者收入相关产品价格嗜好预期买者数量,ShiftsintheDemandCurve,ChangeinDemandAshiftinthedemandcurve,eithertotheleftorright.Causedbyachangeinadeterminantotherthantheprice.,需求曲线的移动,需求的变化需求曲线的移动，向左或者向右。是由价格以外的因素变化引起的。,ShiftsintheDemandCurve,0,D1,PriceofIce-CreamCone,QuantityofIce-CreamCones,D3,D2,Increaseindemand,Decreaseindemand,需求曲线的移动,0,D1,冰激凌蛋卷的价格,冰激凌蛋卷的数量,D3,D2,需求增加,需求减少,ConsumerIncome消费者收入,Asincomeincreasesthedemandforanormalgoodwillincrease.收入增加，正常商品的需求增加Asincomeincreasesthedemandforaninferiorgoodwilldecrease.收入增加，劣等品的需求减少,ConsumerIncomeNormalGood,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,PriceofIce-CreamCone,QuantityofIce-CreamCones,0,Increaseindemand,Anincreaseinincome.,D1,D2,消费者收入正常商品,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,冰激凌蛋卷的价格,冰激凌蛋卷的数量,0,需求增加,收入增加.,D1,D2,ConsumerIncomeInferiorGood,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,PriceofIce-CreamCone,QuantityofIce-CreamCones,0,Decreaseindemand,Anincreaseinincome.,D1,D2,消费者收入劣等品,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,冰激凌蛋卷的价格,冰激凌蛋卷的数量,0,需求减少,收入增加.,D1,D2,PricesofRelatedGoodsSubstitutes&Complements,Whenafallinthepriceofonegoodreducesthedemandforanothergood,thetwogoodsarecalledsubstitutes.Whenafallinthepriceofonegoodincreasesthedemandforanothergood,thetwogoodsarecalledcomplements.,相关物品的价格替代品和互补品,当一种物品价格下降减少了另一种物品需求时，这两种物品被称为替代品。当一种物品价格下降增加了另一种物品需求时，这两种物品被称为互补品。,Table1VariablesThatInfluenceBuyers,Copyright2004South-Western,表1.影响买者的变量,Supply供给,Quantitysuppliedistheamountofagoodthatsellersarewillingandabletosell.供給量是指卖者愿意而且能够出售的一种物品或劳务的数量。,LawofSupply供给规律,Thelawofsupplystatesthatthereisadirect(positive)relationshipbetweenpriceandquantitysupplied.供给规律认为，价格与供給量之间的关系是正关系。,SupplySchedule供给表,Thesupplyscheduleisatablethatshowstherelationshipbetweenthepriceofthegoodandthequantitysupplied.供给表是表示一种物品价格与供給量之间关系的表格。,BensSupplySchedule供给表,SupplyCurve供给曲线,Thesupplycurveistheupward-slopinglinerelatingpricetoquantitysupplied.供给曲线把价格与供給量联系在一起的向右上方倾斜的曲线。,Figure5BensSupplyScheduleandSupplyCurve,riceof,Ice-Cream,Cone,0,2.50,2.00,1.50,1.00,1,2,3,4,5,6,7,8,9,10,11,Quantityof,Ice-CreamCones,$3.00,12,0.50,图5.Ben供给表与供给曲线,冰激凌蛋卷需求量,0,2.50,2.00,1.50,1.00,1,2,3,4,5,6,7,8,9,10,11,冰激凌蛋卷的供給量,$3.00,12,0.50,MarketSupplyversusIndividualSupply,Marketsupplyreferstothesumofallindividualsuppliesforallsellersofaparticulargoodorservice.Graphically,individualsupplycurvesaresummedhorizontallytoobtainthemarketsupplycurve.,市场供给,市场供给是指某种物品或劳务的所有卖者个人供给的总和。从图形上看,把个人供给曲线水平相加，就得出了市场供给曲线。,ShiftsintheSupplyCurve,InputpricesTechnologyExpectationsNumberofproducers,供给曲线的移动,投入要素价格技术预期生产者数量,ChangeinQuantitySuppliedversusChangeinSupply,ChangeinQuantitySuppliedMovementalongthesupplycurve.Causedbyachangeinthemarketpriceoftheproduct.,供給量的变化与供给的变化,供給量的变化沿着供给曲线移动。是由于产品的市场价格变动引起的。,ChangeinQuantitySupplied,1,5,PriceofIce-CreamCone,QuantityofIce-CreamCones,0,S,1.00,A,C,Ariseinthepriceoficecreamconesresultsinamovementalongthesupplycurve.,供給量的变化,1,5,冰激凌蛋卷的价格,冰激凌蛋卷的数量,0,S,1.00,A,C,冰激凌蛋卷的市场价格上升导致供給量沿着供给曲线的移动。,ShiftsintheSupplyCurve,ChangeinSupplyAshiftinthesupplycurve,eithertotheleftorright.Causedbyachangeinadeterminantotherthanprice.,供給曲线的移动,供给的变化供给曲线的移动，向左或者向右。是由于价格以外的因素变化造成的。,ShiftsintheSupplyCurve,PriceofIce-CreamCone,QuantityofIce-CreamCones,0,S1,供给曲线的移动,冰激凌蛋卷的价格,冰激凌蛋卷的数量,0,S1,Table2VariablesThatInfluenceSellers,供給量的变化与供给的变化,SUPPLYANDDEMANDTOGETHER供给与需求的结合,Equilibriumreferstoasituationinwhichthepricehasreachedthelevelwherequantitysuppliedequalsquantitydemanded.市场均衡价格水平达到供給量与需求量相等的状态。,SupplyandDemandTogether,EquilibriumPriceThepricethatbalancessupplyanddemand.Onagraph,itisthepriceatwhichthesupplyanddemandcurvesintersect.EquilibriumQuantityThequantitythatbalancessupplyanddemand.Onagraphitisthequantityatwhichthesupplyanddemandcurvesintersect.,供给与需求的结合,均衡价格使供给与需求平衡的价格。从图形上看，就是供给曲线与需求曲线相交时的价格。均衡数量当价格调整到使供给与需求平衡时的供給量与需求量。从图形上看，就是供给曲线与需求曲线相交时的数量。,SupplyandDemandTogether,DemandSchedule,SupplySchedule,At$2.00,thequantitydemandedisequaltothequantitysupplied!,供给与需求的结合,需求表,供给表,在$2.00时,需求量等于供給量!,Figure8TheEquilibriumofSupplyandDemand,Copyright2003Southwestern/ThomsonLearning,Priceof,Ice-Cream,Cone,0,1,2,3,4,5,6,7,8,9,10,11,12,QuantityofIce-CreamCones,13,表8.供给与需求的均衡,冰激凌蛋卷需求量,0,1,2,3,4,5,6,7,8,9,10,11,12,冰激凌蛋卷的数量,13,Figure9MarketsNotinEquilibrium,Priceof,Ice-Cream,Cone,0,(a)ExcessSupply,Quantityof,Ice-Cream,Cones,图9.非均衡状态的市场,冰激凌蛋卷需求量,0,(a)超额供给,冰激凌蛋卷的数量,Equilibrium,SurplusWhenpriceequilibriumprice,thenquantitysuppliedquantitydemanded.Thereisexcesssupplyorasurplus.Supplierswilllowerthepricetoincreasesales,therebymovingtowardequilibrium.,均衡,过剩当价格高于均衡价格时，供給量大于需求量。存在超额供给或过剩。供给者通过降低价格来增加销售，这使价格向其均衡水平变动。,Equilibrium,ShortageWhenpricethequantitysupplied.Thereisexcessdemandorashortage.Supplierswillraisethepriceduetotoomanybuyerschasingtoofewgoods,therebymovingtowardequilibrium.,均衡,短缺当价格低于市场均衡价格时，需求量超过了供給量。存在着超额需求或短缺。由于太多卖者要购买太少的物品，供给者将提高价格。因此价格将趋向于市场均衡价格。,Figure9MarketsNotinEquilibrium,Priceof,Ice-Cream,Cone,0,Quantityof,Ice-Cream,Cones,(b)ExcessDemand,图9.非均衡状态的市场,冰激凌蛋卷需求量,0,冰激凌蛋卷的数量,(b)超额需求,Equilibrium均衡,Lawofsupplyanddemand供需规律Theclaimthatthepriceofanygoodadjuststobringthequantitysuppliedandthequantitydemandedforthatgoodintobalance.认为任何一种物品价格的调整都会使该物品供求平衡的观点。,ThreeStepsToAnalyzingChangesinEquilibrium,Decidewhethertheeventshiftsthesupplyordemandcurve(orboth).Decidewhetherthecurve(s)shift(s)totheleftortotheright.Usethesupply-and-demanddiagramtoseehowtheshiftaffectsequilibriumpriceandquantity.,分析均衡的三个步骤,确定该事件是使供给曲线移动，还是使需求曲线移动，或者使两种曲线都移动。确定曲线是向右移动，还是向左移动。用供求图来考察这种移动如何影响均衡价格和数量。,HowanIncreaseinDemandAffectstheEquilibrium,PriceofIce-CreamCone,2.00,0,7,QuantityofIce-CreamCones,Supply,Initialequilibrium,D1,1.Hotweatherincreasesthedemandforicecream.,需求增加如何影响均衡,冰激凌蛋卷的价格,2.00,0,7,冰激凌蛋卷的数量,供给,原来的均衡,D1,1.天气热使冰激凌需求增加.,HowaDecreaseinSupplyAffectstheEquilibrium,PriceofIce-CreamCone,2.00,0,1,2,3,4,7,8,9,11,12,QuantityofIce-CreamCones,13,Demand,Initialequilibrium,S1,10,1.Anearthquakereducesthesupplyoficecream.,Newequilibrium,供给减少如何影响均衡,冰激凌蛋卷的价格,2.00,0,1,2,3,4,7,8,9,11,12,冰激凌蛋卷的数量,13,需求,原来的均衡,S1,10,地震减少了冰激凌的供给.,新均衡,WhatHappenstoPriceandQuantityWhenSupplyorDemandShifts?,当供给或需求变动时，价格和数量会发生什么变化?,Summary,Economistsusethemodelofsupplyanddemandtoanalyzecompetitivemarkets.Inacompetitivemarket,therearemanybuyersandsellers,eachofwhomhaslittleornoinfluenceonthemarketprice.,小结,经济学家用供求模型来分析竞争市场。在竞争市场中，有许多买者和卖者，他们当中的任何一个对市场价格具有极小或者没有影响力。,Summary,Thedemandcurveshowshowthequantityofagooddependsupontheprice.Accordingtothelawofdemand,asthepriceofagoodfalls,thequantitydemandedrises.Therefore,thedemandcurveslopesdownward.Inadditiontoprice,otherdeterminantsofhowmuchconsumerswanttobuyincludeincome,thepricesofcomplementsandsubstitutes,tastes,expectations,andthenumberofbuyers.Ifoneofthesefactorschanges,thedemandcurveshifts.,小结,需求曲线表示一种物品的需求量如何取决于价格。根据需求规律，当一种物品价格上升时，需求量减少。所以需求曲线是下倾的。除了价格以外，决定需求量的其它因素包括收入、替代品和互补品的价格、嗜好、预期，以及买者的数量。如果这些变量中的任何一个变化，导致