微观经济学英文课件Ch_08

Application:theCostsofTaxation应用：税收的成本Chapter8TheCostofTaxation征税的成本•Howdotaxesaffecttheeconomicwell-beingofmarketparticipants?–税收如何影响市场参与者的经济福利？•Itdoesnotmatterwhetherataxonagoodisleviedonbuyersorsellersofthegood…thepricepaidbybuyersrises,andthepricereceivedbysellersfalls.–对某商品征税时由买者支付还是卖者支付其实无关紧要……结果都是买者支付的价格上升而卖者受到的价格下降。TheEffectsofaTax...税收的效应Price0QuantityQuantitywithouttaxSupplyDemandPricewithouttaxPricebuyerspayQuantitywithtaxSizeoftaxPricesellersreceiveTheEffectsofaTax•Ataxplacesawedgebetweenthepricebuyerspayandthepricesellersreceive.–税收在买者支付的价格和卖者收到的价格之间打入一个楔子。•Becauseofthistaxwedge,thequantitysoldfallsbelowthelevelthatwouldbesoldwithoutatax.–因为这个税收楔子，销售量下降到没有税收是的销售水平之下。•Thesizeofthemarketforthatgoodshrinks–这个商品的市场规模因之萎缩。TaxRevenueT=thesizeofthetaxQ=thequantityofthegoodsoldTQ=thegovernment’staxrevenueTaxRevenue...Price0QuantityQuantitywithouttaxSupplyDemandPricesellersreceiveQuantitywithtaxSizeoftax(T)Quantitysold(Q)TaxRevenue(TxQ)PricebuyerspayHowaTaxAffectsWelfare...Quantity0PriceDemandSupplyQ1ABCFDEQ2Taxreducesconsumersurplusby(B+C)andproducersurplusby(D+E)Taxrevenue=(B+D)DeadweightLoss=(C+E)Pricebuyerspay=PBP1Pricewithouttax=PSPricesellersreceive=ChangesinWelfarefromaTaxWithoutTaxWithTaxChangeConsumerSurplusA+B+CA-(B+C)ProducerSurplusD+E+FF-(D+E)TaxRevenuenoneB+D+(B+D)TotalSurplusA+B+C+D+E+FA+B+D+F-(C+E)TheareaC+Eshowsthefallintotalsurplusisthedeadweightlossofthetax.HowaTaxaffectswelfare税收如何影响福利•Thechangeintotalwelfareincludes:–总得福利变化包括：•Thechangeinconsumersurplus.–消费者剩余的变化•Thechangeinproducersurplus.–生产者剩余的变化•Thechangeintaxrevenue.–税收总额的变化•Thelossestobuyersandsellersexceedtherevenueraisebythegovernment.–买者和卖者的损失超过了政府征收的税收总额•Thefallintotalsurplusiscalledthedeadweightloss.–总福利中下降的那部分就称为无谓损失DeadweightLossandtheGainsfromTrade•Taxescausedeadweightlossesbecausetheypreventbuyersandsellersfromrealizingsomeofthegainsfromtrade.–税收之所以导致无谓损失是因为它阻碍了买者和卖者从交易中获得的利益。TheDeadweightLoss...Quantity0PriceDemandSupplyQ1PBPrice=P1withouttaxPSQ2SizeoftaxLostgainsfromtradeCosttosellersValuetobuyersReductioninquantityduetothetaxDeterminantsofDeadweightLoss•Whatdetermineswhetherthedeadweightlossfromataxissmallorlarge?–什么决定了税收导致的无谓损失的大小？•Themagnitudeofthedeadweightlossdependsonhowmuchthequantitysuppliedandquantitydemandedrespondtochangesintheprice.–无谓损失的大小依赖于价格变化所引起的供给量和需求量的变化。•That,inturn,dependsonthepriceelasticitiesofsupplyanddemand.–或者说依赖于供需的价格弹性。TaxDistortionsandElasticities...税收扭曲和弹性QuantityPriceDemandSupply0Whensupplyisrelativelyinelastic,thedeadweightlossofataxissmall.(a)InelasticSupply(a)供给缺乏弹性SizeoftaxQuantityPriceDemandSupply0SizeoftaxWhensupplyisrelativelyelastic,thedeadweightlossofataxislarge.(b)ElasticSupply(b)供给富有弹性TaxDistortionsandElasticities...税收扭曲和弹性QuantityPriceDemandSupply0Whendemandisrelativelyinelastic,thedeadweightlossofataxissmall.(c)InelasticDemand需求缺乏弹性SizeoftaxTaxDistortionsandElasticities...税收扭曲和弹性QuantityPriceDemandSupply0SizeoftaxWhendemandisrelativelyelastic,thedeadweightlossofataxislarge.(d)ElasticDemand需求富有弹性TaxDistortionsandElasticities...税收扭曲和弹性DeterminantsofDeadweightLoss无谓损失的决定因素•Thegreatertheelasticitiesofsupplyanddemand–供需的价格弹性越大•Thelargerwillbethedeclineintheequilibriumquantityand,–均衡数量的下降越大•Thegreaterthedeadweightlossofatax.–税收带来的无谓损失也就越大TheDeadweightLossDebate•Someeconomistsarguethatlabortaxesarehighlydistortingandbelievethatlaborsupplyismoreelastic.–有的经济学家认为劳动税扭曲效应很高，并且认为劳动的供给富有弹性。•Someexamplesofworkerswhomayrespondmoretoincentives.（工人对激励反应强烈的例子）–Workerswhocanadjustthenumberofhourstheywork.•有的工人可以调整自己工作的时间。–Familieswithsecondearners（家庭里有几个职工的）–Elderlywhocanchoosewhentoretire.•年长的工人可以选择退休。–Workersintheundergroundeconomy.•地下经济体中的工人。DeadweightLossandTaxRevenueasTaxVary•Witheachincreaseinthetaxrate,thedeadweightlossofthetaxrisesevenmorerapidlythanthesizeofthetax.–当税率增加时，其带来的无谓损失比税收规模增加的速度更快。DeadweightLossandTaxRevenue.PBQuantityQ20PriceQ1DemandSupplyTaxrevenuePSDeadweightloss(a)SmallTaxDemandSupplyTaxrevenuePBQuantityQ20PriceQ1PSDeadweightloss(b)MediumTaxDeadweightLossandTaxRevenue.DeadweightLossandTaxRevenue.PBQuantityQ20PriceQ1DemandSupplyPSDeadweightloss(c)LargeTaxDeadweightLossandTaxRevenue•Forthesmalltax,taxrevenueissmall.–税率低时，税收总额也比较小。•Asthesizeofthetaxrises,taxrevenuegrows.–随着税率的增加，税收总额增加。•Butasthesizeofthetaxcontinuetorise,taxrevenuefallsbecausethehighertaxreducesthesizeofthemarket.–但是当税率持续增加时，税收总额下降。因为过高的税率缩小了市场规模。DeadweightLossandTaxRevenueVarywiththeSizeoftheTax...(a)DeadweightLossDeadweightLoss0TaxSize(b)Revenue(theLaffercurve)TaxRevenue0TaxSizeTheLafferCurve拉弗曲线•Asthesizeofataxincreases,itsdeadweightlossquicklygetslarger.–随着税率的增加，它带来的无谓损失迅速变得更大。•Bycontrast,taxrevenuefirstriseswiththesizeofatax;butthen,asthetaxgetslarger,themarketshrinkssomuchthattaxrevenuestartstofall.–对应地，开始时税收总额随税率上升而增加，但当税率越来越高时，市场萎缩太大以至税收总额开始下降。DeadweightLossandTaxRevenueVarywiththeSizeoftheTax...TheLafferCurveandSupply-sideEconomics•TheLaffercurvedepictstherelationshipbetweentaxrateandtaxrevenue.–拉弗曲线描绘了税率和税收收入之间的关系•Supply-sideeconomicsreferstotheviewsofReaganandLafferwhoproposedthatataxcutwould