学堂2017cfa一级经济学课件

（苹果和安卓系统可直接进入Appstore搜索 学堂 的课程啦（课程有效期为1年） ：

： FinancialReportingFinancialReportingCorporatePortfolioManagementandEquityFixedAlternative SS4MicroeconomicsandR14Topicsindemandand R15ThefirmandmarketR16Aggregateoutput,price,andeconomicSS5MonetaryandFiscal,InternationalTradeandR18MonetaryandR20Currencyexchange StudySession ReadingReadingReadingReading

DemandandSupply ysis:IntroductionDemandandSupply ysis:ConsumerDemandDemandandSupply ysis:TheFirmTheFirmandMarketStudySession ReadingReadingReading

AggregateOutput,Prices,andEconomicGrowthUnderstandingBusinessCyclesMonetaryandStudySession EconomicsinaGlobalReadingReading

InternationalTradeandCapitalFlowsCurrencyExchangeRates SS4MicroeconomicsandR14Topicsindemandand R15ThefirmandmarketR16Aggregateoutput,price,andeconomicsSS5MonetaryandFiscal,InternationalTradeandR18MonetaryandIritang StudySession ReadingReadingReadingReading

DemandandSupply ysis:IntroductionDemanda rDemandnd ysis:nd ysis:nd ysis:TheTheFirmandMarketStudySession ReadingReadingReading

AggregateOutput,Prices,andEconomicGrowthandingBusneandingBusnesnalTradeandCapitalxchangeStudynalTradeandCapitalxchangeReadingReading

CurrencyE SS4MicroeconomicsandpicsindemandpicsindemandandfirmandmarketR15gregateoutputprice,andgregateoutputprice,andR17 SS5MonetaryandFiscal,InternationalTradeandR18Monetaryandencyexchangeencyexchange SS4MicroeconomicsandR14Topicsindemandand SubstitutionandeNormalgoodsandinferiorBreakevenandshutdownEconomiesof SS4MicroeconomicsandR15Thefirmandmarket4Pure SS4MicroeconomicsandR16Aggregateoutput,price,andeconomic +AD+ SS4Microeconomicsand4Theoriesofbusiness SS5MonetaryandFiscal,InternationalTradeandR18Monetaryand SS5MonetaryandFiscal,InternationalTradeandR19InternationaltradeandcapitalRModel+H-O SS5MonetaryandFiscal,InternationalTradeandR20CurrencyexchangeSpotandforwardInterestrateForwardExchangerateEffectsofexchange ：

SS4MicroeconomicsandR14Topicsindemandand R15ThefirmandmarketR16Aggregateoutput,price,andeconomicSS5MonetaryandFiscal,InternationalTradeandR18MonetaryandR19InternationaltradeandcapitalR20Currencyexchange TopicsinDemandand ofdemand ofdemandPriceelasticityofsupply

ofdemandeelasticityofdemand PriceElasticityof Priceelasticityisameasureoftheresponsivenessofthe tydemandedtoachangeinprice.ThePriceofelasticityofdemand=%change tydemand %changeinprice endingaverage endingvalue+beginningvalue2 2 PriceElasticityof Ifasmallpercentagepricechangeresultsinalargepercentagechangein demanded,thedemandforthatgoodissaidtobehighlyelastic.Theabsolutevalueofpriceelasticityisgreaterthanone.Ifalargepercentagepricechangeresultsinasmallpercentagechangein demanded,demandisrelativelyinelastic.Theabsolutevalueofpriceelasticityislessthanone.Aperfectlyelasticdemandcurvehorizontal,anditselasticityisinfinite.Ifthepriceincreases, demandedgoestozero.Aperfectlyinelasticdemandcurveisvertical,andelasticityiszero.Ifthepricechanges,therewillbenochange

PerfectlyPerfectlyin ty PriceElasticityof TherelationbetweenpriceelasticityofdemandandtotalTotalrevenueis izedatthepriceand tywheredemandisunitelastic(priceelasticity=－1)andsodecreaseswithbothpriceincreasesorpricedecreasesfromthatlevel.Whenpriceisintheelastic(inelastic)regionofthedemandcurve,apriceincreasewilldecrease(increase)totalrevenue.WhenEp>1,ifpriceincreases,the willdecrease,andthechangein tyisgreaterthanthatinprice.Asaresult,thetotalrevenuewilldecrease. ElasticityofSupplyandDemandandTaxIncide联n系电Ithesupplycurveislesselastic,sellerswillbearahighertaxIfthedemandcurveislesselastic,buyerswillbearahighertaxIfelasticityofeitherdemandorsupplydecreases,thedeadweightlosswilldecrease.(compareFigureawithFigurec) ElasticityofSupplyandDemandandTaxIncide联n系电话ThedifferencebetweenthetotalvaluetoconsumersoftheunitsofagoodthatbuyandthetotalamounttheymustpayforthoseunitsiscalledconsumerProducersurplusistheexcessofthemarketpriceabovetheopportunitycostofTotalsurplus=consumersurplus+producerPA B FactorsthatInfluencetheElasticityof Availabilityofsubstitutes.Ifgoodsubstitutesareavailable,apriceincreaseinproductwillinduceconsumerstoswitchtoasubstituteRelativeamountofespentonthegood.Whentheportionofconsumerbudgetsspentonaparticulargoodisrelativelysmall,demandforthatgoodwilltendtoberelativelyinelastic.Timesincethepricechange.Thepriceelasticityofdemandformostproductsgreaterinthelongrunthanintheshort Cross Crosselasticityofdemandmeasuresthechangeinthedemandforagoodinresponsetothechangeinpriceofasubstituteorcomplementarygood.Theformulacrosselasticityofdemand

ty =DQA/%changeinpriceofsubstituteor CrosselasticityofdemandispositiveforsubstituteCrosselasticityofdemandisnegativeforcomplementary eElasticityof eelasticityofdemandmeasuresthesensitivityofthe tyofagoodorservicedemandedtoachangeinaconsumer’se.Theformulaeelasticityof %change ty Q/%changein I/ TheapplicationofeNormalGoods:positiveeelasticity,demandriseswithe.(>Luxuries:highpositiveelasticity,demandrisesstronglywithe.Necessities:normalbutlowelasticity(betweenInferiorGoods:negativeeelasticity,demandfallswithe Qxd=8,400-400Px+60I-choose$3for$50(thousands)for$20(thousands)forQx Qx D

=-0.12fiown-priceelasticityofdemandxQ xQdE dE

= x d

d=QxQ

3E PE PyQpd xQpd DPyx

=-10·20 =-0.02ficross-priceelasticity Substitutionande SubstitutionWhenthepriceofGoodXdecreases,therelativepriceofGoodXagainstothergoodswilldecrease.Consumerequilibriummovesalongtheindifferencecurve,whichleadstoanincreaseinthedemandofGoodX.eWhenthepriceofGoodXdecreases,consumer’srealpurchasingpowerwillchange.Realeincreases,andbudgetconstraintmoves,whichleadtoachangeinthedemandofGoodX.eeffect&SubstitutioneffectWhendecreaseinthepriceofGoodThesubstitutioneffectispositive,andtheeeffectisalsopositive→consumptionofGoodXwillThesubstitutioneffectispositive,andtheeeffectisnegativebutsmallerthantheeffect→consumptionofGoodXwillThesubstitutioneffectispositive,andtheeeffectisnegativeandlargerthanthesubstitution→consumptionofGoodXwill Substitutionande Positivee Substitutionande NegativeeEffect,SmallerThanSubstitution Substitutionande NegativeeEffect,LargerThanSubstitution NormalGoodsandInferior NormalgoodisoneforwhichtheeeffectisInferiorgoodisoneforwhichtheeeffectisGiffengoods(priceeeffect（inferiorgoods）>SubstitutiondemandcurvehaspositiveVeblengoods(priceConsumercannottrulyvalueagooduntilthepriceisPriceisusedbytheconsumertosignalthestatusintheHigh high high tyhaveapositivelyslopeddemandcurve(eg:Guccibag)Butwhenpriceincreases,theslopemaybeTwoimportantdistinctionsbetweenGiffengoodsandVeblenGiffengoodsareinferiorgoods(negativeeeffect),whileVeblengoodscertainlyareTheexistenceofGiffengoodsistheoreticallysupportedbyourrulesofconsumerchoice,

NormalGoodsandInferior SummaryforsubstitutioneffecandeRelationbetweensubsitutioneffectandpriceRelationbetweeneeffectandRelationbetweentotaleffectandShapeofdemandNormalInferiorGiffen Factorsof Factorsofproduction,theinputstotheproductionofgoodsandservices,Land,asinthesitelocationoftheLabor,whichconsistsoftheinputsofskilledandunskilledworkersaswellastheinputsoffirms’managers;Capital,whichinthiscontextreferstophysicalcapital–suchtangiblegoodsasequipment,tools,andbuildings.Capitalgoodsaredistinguishedasinputstoproductionthatarethemselvesproducedgoods;Materials,whichinthiscontextreferstoanygoodsthebusinessbuysasinputstoitsproductionprocess.For ysis,weoftenconsideronlytwoinputs,capitalandProductionfunction:the tyofoutputthatafirmcanproducecanbethoughtofasafunctionoftheamountsofcapitalandlaboremployedandrepresentedasQ=f(K,L). LawofDiminishing

：Thelawofdiminishingreturnsstatesthatasmoreandmoreresources(suchaslabor)aredevotedtoaproductionprocess,theyincreaseoutputbutataneverdecreasingrate. LawofDiminishing

AverageandMarginalCosts

ATC=AFC+AVCMC

ATCQ

AVCAFC IfAR<AVCintheshortrun,thefirmshouldshutdown.Thisisitsshort-runshutdownIfAR>AVCintheshortrun,thefirmshouldcontinuetooperate,evenifithasInthelongrunthefirmshouldshutdownifAR<ATC.Thisisthelong-runshutdownIfAR=ATC,totalrevenueisjustequaltototal(economic)cost,andthisisthefirm'sbreakevenpoint. 02IfAR≥ATC,firmshouldstayinthemarketinboththeshortandlongrun.Notes:inanotherway,wecancompareTRtoTCIfAR≥AVC,butAR<ATC,thefirmshouldstayinmarketintheshortrunbutwillexitthemarketinthelongrunIfAR<AVC,thefirmshouldshutdownintheshortrunandexitthemarketinthelongNotes:inanotherway,wecancompareTRto P

OperateinP ShutdowninSRand TR=TC:TC>TR>TVC:firmshouldcontinuetooperateintheshortrunbutshutdowninthelongTR<TVC:firmshouldshutdownintheshortrunandthelongBecausepricedoesnotequalaveragerevenue(ormarginalrevenue)forafirminimperfect ysisbasedontotalcostsandrevenuesisbettersuitedforexaminingbreakevenandshutdownpoints.Revenue-CostShort-RunLong-RunTRStayinStayinTR>TVCbutTR<TFC+TVCStayinExitTR<ShutdownproductiontoExit EconomiesofScaleandDiseconomiesof Thedownwardslo segmentofthelong-runaveragetotalcostcurveindicatestheeconomiesofscale.Theupwardslo segmentofthislong-runaveragetotalcostcurveindicatesthatdiseconomiesofscalearepresentwhenaverageunitcostsriseasthescaleofthebusinessincreases SS4MicroeconomicsandR14Topicsindemandand R15ThefirmandmarketR16Aggregateoutput,price,andeconomicSS5MonetaryandFiscal,InternationalTradeandR18MonetaryandR19InternationaltradeandcapitalR20Currencyexchange TheFirmandMarket NumberoffirmsandtheirrelativeElasticityofthedemandcurvestheyWaysthattheycompetewithotherfirmsforEaseordifficultywithwhichfirmscanenterorexitthe Number

Degree

Shape

：Difficulty

Theexample

Morethanone,butnot

differenceofNoLittleornoSoleproduct,nearlyno

enterorNo

ourSomeretail ,Public Perfect TheassumptionofperfectAllthefirmsinthemarketproduceidenticalThereisalargenumberofindependentEachsellerissmallrelativetothesizeofthetotalTherearenobarrierstoentryorApricetakerisafirmthatcannotinfluencethemarketpriceandthatsetsitsownpriceatthemarketprice.Individualfirm’sdemandscheduleisperfectlyelastic(horizontal,Price=Demand=MarginalRevenue=Averagerevenue)Thekeyreasonwhyaperfectlycompetitivefirmisthatitproducesatinyproportionofthetotaloutputofaparticulargoodandbuyersarewellinformedaboutthepricesofotherfirms.Determinetheprofit izingoutput: izeeconomic izationunderPerfect联系405 Short-RunLossunderPerfect Short-runP<ATC:economicAVC<P<ATC:operatingintheshort-run,exitinthelongP=AVC:shutdownP<AVC:exitinbothshort-runandlong- EquilibriuminaPerfectlyCompetitive Thelong-runequilibriumoutputlevelforperfectlycompetitivefirmsiswhereMR=MC=ATC,whichiswhereATCisataminimum.Atthisoutput,economicprofitiszeroandonlyanormalreturnisrealized.Inequilibrium,eachfirmisproducingthe tyforwhichP=MR=MC=ATC,sothatnofirmearnseconomicprofits. Short-runsupplycurveforafirmisitsMClineabovetheaveragevariablecostcurve,AVC.Short-runmarketsupplycurveisthehorizontalsum(addupthe tiesfromallfirmsateachprice)oftheMCcurvesforallfirmsinagivenindustry. Short-RunChangein Intheshortrun,anincreaseinmarketdemandwillincreasebothequilibriumprice ty,whileadecreaseinmarketdemandwillreducebothequilibriumprice Inthelongrun,iffirmsinanindustryareShort-runadjustmenttoanincreaseindemandunderperfect ThefollowingmarketandproductfeaturesdefinemonopolisticTherearealargenumberofindependenteachfirmhasrelativesmallmarketfirmneedonlypayattentiontoaveragemarkettoomanyfirmsforcollusiontobeEachsellerproducesadifferentiatedThemostdistinctivefactorinmonopolisticcompetitionisproductFirmscompeteonproductquality,priceandFirms toenterandFirmsinmonopolisticcompetitionfacedownward-slo demandcurvesandthecurvesarehighlyelasticbecausecompetingproductsareperceivedby consumersasclose Monopolisti 由此确定

TheentryofnewfirmshiftsthedemandcurvefacedbyeachindividualfirmdowntothepointwhereP=ATCNoeconomic FirmOutputunderMonopolisticandPerfect675P>MC,suggestinginefficientallocationofPriceisslightlyhigherthanunderperfect ProductdevelopmentandInnovationandproductLess-elasticdemandcurve,earneconomicClosesubstitutesandimitationswilleventuallyerodetheinitialeconomicContinuallylookforinnovativeproductHighforfirmsinmonopolisticInformconsumersabouttheuniquefeaturesoftheAdvertingcostsaregreater,andincreasetheATCOutputIfadvertisingleadstoenoughofanincreaseinoutput(sales),itcanactuallydecreaseafirm’saveragetotalcostBrandProvideinformationtoconsumerbyprovidingthemwithsignalsaboutthequalityofthebrandedproduct. OligopolyisaformofmarketcompetitioncharacterizedasmallnumberofinterdependenceamonglargeeconomiesofsignificantbarrierstoeithersimilarordifferentiatedComparedtomonopolisticcompetition,anoligopolymarkethashigherbarrierstoentry,fewerfirms,and,typically,lesselasticfirmdemandcurves.Incontrasttoamonopolist,oligopoliesarehighlydependentupontheactionsoftheirrivalswhenmakingbusinessdecisions.FourmodelsofKinkeddemandcurveCournotduopolyNashequilibriummodel(prisoner’sStackelbergdominantfirm Kinkeddemand Thekinkeddemandcurvemodelofoligopolyisbasedontheassumptionthateachfirmbelievesthatifitraisesitsprice,otherswillnotfollow,butifitcutsitsprice,otherfirmswillcuttheirs.BetweenrangeAandB,theoptimumQisconstant,can'tdetermineQkisthe izinglevelofoutputandthepriceatwhichthekinklocatedisthefirm’s izing ing:itispletebecausewhatdeterminesthemarketprice(wherethekinkislocated)isoutsidethescopeofthemodel. Cournot Cournotonlytwofirmscompeting(eg:abothhaveidenticalandconstantmarginalcostsofeachfirmknowsthe dbytheotherfirminthepreviousperiodandassumesthatiswhatitwillsupplyinthenextperiodconstructademandcurveandmarginalrevenuecurveforitsown Firmsdeterminetheir tiessimultaneouslyeachperiodand,undertheassumptionsoftheCournotmodel,these tieswillchangeeachperioduntiltheyareequal.Wheneachfirmselectsthesame ty,thereisnolongeranyadditionalprofittobegainedbychanging ty,andwehaveastableequilibrium.Theresultingmarketpriceislessthantheprofit izingpricethatamonopolistwouldcharge,buthigherthanmarginalcost,thepricethatwouldresultfromperfectMorefirmsareaddedtothemodel,theequilibriummarketpricefallstowardsmarginalcost,whichistheequilibriumpriceinthelimitasthenumberoffirmsgetslarge. Cournot Cournotmodelcouldbe inedastheAggregatemarketdemand:Q=450-P,Q=q1+q2,whereq1andq2representtheoutputlevelsofthetwofirms.ThesupplyfunctionisrepresentedbyconstantmarginalcostMC=30.Rearrangingtheaggregatedemandfunctionintermsofprice,weget:P=450-Q=450-q1-q2,andMC=30 Totalrevenueforeachofthetwofirms:Fortheprofit- izingoutput,setMR=MC,or450-2q1-q2=30and450-2q2-q1=30Findthesimultaneousequilibriumforthetwofirmsbysolvingthetwoequationswithtwounknowns:450-2q1-q2=450-2q2-q1Becauseq1=q2underCournot’sassumption,insertthissolutionintothedemandfunctionandsolvesas:450-2q1-q1=450-3q1=30Therefore,q1=140,q2=140,andThepriceisP=450–280 NashEquilibriumModel(Prisoner’s Nashequilibriumisreachedwhenthechoicesofallfirmsaresuchthatthereisnootherchoicethatmakesanyfirmbetteroff(increasesprofitsordecreaseloss)Prisoners’Dilemmaisagamethatillustratesthatthebestcourseofactionforanoligopolyfirm,whenengagingincollusionwithanotheroligopolyfirm,istocheat. BestoveralleisforbothtoremainsilentandgetsentencesofsixButitisnotTheNashequilibriumisforbothprisonerstoconfess,andforeachtogetasentenceoftwoyears. llyreducehissentencebychangingtoPrisonerBis PrisonerBAAgets2Bgets2ABgets10Agets10BAgets6Bgets6PrisonerAis Collusioniswhenfirmsmakeanagreementamongthemselvestoavoidvariouscompetitivepractices,particularlypricecompetition.Ifthetwopartiescomplywiththecollusion,themarketisjustlikeamonopolyfirm,whichwillmakelessoutputsandhigherprice.Collusiveagreementstoincreasepriceinanoligopolymarketwillbemoresuccessful(havelesscheating)when:TherearefewerProductsaremoresimilar(lessCoststructuresaremorePurchasesarerelativelysmallandRetaliationbyotherfirmsforcheatingismorecertainandmoreThereislessactualorpotentialcompetitionfromfirmsoutsidethe Collusionvs.Perfect Theresultingpricewillbetweenthepricebasedonperfectcollusionthatwouldizetotalprofitstoallfirmsinthemarket(actuallythemonopolyprice)andthepricethatwouldresultfromperfectcompetitionandgeneratezeroeconomicprofitsinthelongrun.Twolimitinges:PcollusionwithQcollusionforperfectcollusionandpetitionandpetitionforperfectcompetition DominantFirm DominantfirmasinglefirmhasasignificantlylargemarketgreaterlowercostmarketpriceisessentiallydeterminedbythedominanttheothercompetitivefirmstakethismarketpriceasTheorderofdecision:1fi2fi3fi Amonopolyischaracterizedasinglesellerofawell-definedproductforwhichtherearenogoodhighbarrierstotheentryofotherfirmsintothemarketfortheTypesofLegalbarrierstoentrycreatelegalmonopoly.Alegalmonopolyisamarketinwhichcompetitionandentryarerestrictedbythegrantingofapublicfranchise,ernmentlicense,patentorExample:radio evisionNaturalbarrierstoentrycreatenaturalmonopoly,whichisanindustryinwhichonefirmcansupplytheentiremarketatalowerpricethantwoormorefirmscan.(Economiesofscale)Example:electric Amonopolistfacesadownwardslo demandcurve.JustaspricesearcherswithlowentrybarrierswillexpandoutputuntilMR=MC,sodomonopolists.Thiswillizeprofit.Positiveeconomicprofitscanexistinthelongrunduetothehighentrybarriers.Themonopolistswantto izeprofits,notprice.Sotheywillnotchargethehighestpossibleprice.MonopolistswillnotmakeprofitsiftheATClineisalwaysabovethedemandComparedtoaperfectcompetitiveindustry,themonopolyfirmwillproducelesstotaloutputandchargeahigherprice.Twopricingstrategiesthatpossibleforamonopolyfirmaresingle-priceandprice Short-runcostsand

：Monopolistsarepricesearchers(facedownwardslo demandcurves)andhaveimperfectinformationaboutdemand,sotheymustexperimentwithdifferentprices(search)tofindthe izingprice/ izeprofit,monopolistswillexpandoutputuntilmarginalrevenue(MR)equalsmarginalcost(MC).Economicprofit=(P*-ATC*) Price Pricediscriminationisthepracticeofchargingdifferentconsumersdifferentpricesforthesameproductorservice.first-degreepricediscrimination,whereamonopolistisabletochargeeachcustomerthehighestpricethecustomeriswillingtopay.Inpractice,themonopolistisabletomeasurehowoftentheproductisusedandchargesthecustomerthehighestpricetheconsumeriswillingtopayforthatunitofgood.Anotherpossibilityisthatpublicpricedisclosureisnon-existent,sothatnocustomerknowswhattheothercustomersarepaying. noteveryconsumerisworseoffinthiscase,becausesomeconsumersmaybechargedapricethatisbelowthatofperfectcompetition,aslongasthemarginalrevenueexceedsthemarginal Price Insecond-degreepricediscrimination,themonopolistoffersa ty-basedpricingoptionsdesignedtoinducecustomerstoself-selectbasedonhowhighlytheyvaluetheproducerscanusenotjust tybutalsothequalitytochargemoretocustomersthatvaluetheproducthighly.segregatedbydemographicorotherForpricediscriminationtoworktheseller demandcurve(priceAtleasttwoidentifiablegroupsofcustomerswithdifferentpriceelasticitiesofdemandfortheproductPreventthecustomerspayingthelowerpricefromresellingtheproducttothecustomerspayingthehigherprice(noarbitrage) Price Pricediscriminationreducesthisinefficiencybyincreasingoutputtowardthe tywheremarginalbenefitequalsmarginalcost,andthedeadweightlossissmaller.ExtremeCase:Ifitwerepossibleforthemonopolisttochargeeachconsumerthe umtheyarewillingtopayforeachunit,wherewouldbenodeadweightloss,sinceamonopolistwouldproducethesame asunderperfectcompetition.Withperfectpricediscriminationtheconsumersurpluswouldallbecapturedbythemonopolist. Price gainsfrompricediscrimination:Aslongasafirmhasgroupsofcustomerswithdownwardfacingdemandcurves,profitscanbeincreasedthroughpricediscrimination.WinnersandPricediscriminationreducestheallocativeinefficienciesthatresultfrompricingabovemarginalcost.Themajorbenefitismoreoutputandprofit.Thefirmgainsfromthosecustomerswithinelasticdemandcurveswhilestillprovidinggoodstocustomerswithmoreelasticdemandcurves.Thismayevencauseproductiontotake cewhenitwouldnot Comparedwithaperfectlycompetitiveindustry,themonopolyfirmwillproducelesstotaloutputandchargeahigherprice.MonopolycreatesadeadweightlossrelativetoperfectAfurtherlossofefficiencyresultsfromrentseekingwhenproducersspendtimeandresourcestotrytoacquireorestablishamonopoly. Regulatorsoftenattempttoincreasecompetitionandefficiencythrougheffortstoreduceartificialbarrierstotrade,suchaslicensingrequirement,quotas,andernmentAveragecostpricingisthemorecommonformofregulationatthepointwhereATC=D.Thiswill:IncreaseoutputanddecreaseIncreasesocialwelfare(allocativeEnsurethemonopolistanormalprofit(butnoeconomicprofit)since MarginalcostpricingwhichisalsoreferredtousefficientsthemonopolisttoreducepricetothepointwhereMC=D.thisIncreaseoutputandreduceCausesthemonopolisttoincuralosssincepriceisbelowSuchasolutionrequiresa ernmentsubsidyinordertoprovidethefirmwithanormalprofit.Anotherwayof“regulating”amonopolyisforthe ernmenttosellthemonopolyrighttothehighestbidder. AverageCostPricingandMarginalCost Somereasonsmake ernmentgoastraywhendealingwithproblemsassociatedwithmarketswithhighbarrierstoentry.Lackofinformation(notknowtheATC,Costshifting.Thefirmhasnoincentivetoreducecosts.(Ifthefirmallowscoststorise,theregulatorwillallowpricestoincrease)Qualityregulations(It’seasiertoregulatepricethanitistoregulateSpecialinteresteffect.Thefirmmaytrytoinfluenceregulationbypoliticalmanipulation.(rent-seeking) Summarypricingstrategyundereachmarket系电话Perfect ization:And ization:Becausethefirm’sdemandcurveisdownward ,Monopolistic ization:Becausethefirm’sdemandcurveisdownward , Summarypricingstrategyundereachmarket系电话Becausethekeycharacteristicsofoligopolyistheinterdependenceoffirm’spricingandoutputdecisions,theoptimalpricingstrategydependsonassumptionsaboutthereactionofotherfirmstoeachfirm’sactions.KinkeddemandFirmsproduceQforwhich MCcurve,soformanycoststructurestheoptimalQisthesame,giventhesamedemandcurve.Ifsuccessful,sameasthecaseinDominantfirmDominantfirm:MR=MC,chargethepriceonthefirm’sdemandOtherfirms:takethatpriceandproduce tyforwhich Summarypricingstrategyundereachmarket系电话Oligopoly:GameReactionofcompetitorsdeterminetheoptimaloutputandpricingGiventhevarietyofmodelsandassumptionsaboutcompetitorreactions,thelong-runeisindeterminate:PPC<P<PMON ConcentrationElasticityofdemand,TheN-FirmConcentrationRatio:thesumorthepercentagemarketsharesofthelargestNfirmsinaadvantage:simpletodisadvantage:doesnot fymarketlimitation:itmayberelativelyinsensitivetomergersoftwofirmswithlargemarketTheHerfindahl-Hirs anIndex(HHI):thesumofthesquaresofthemarketsharesofthelargestfirmsinthemarket.limitation:bothofoursimpleconcentrationmeasuresisthatbarrierstoentryarenotconsideredineithercase.Evenafirmwithhighmarketsharemaynothavemuchpricingpowerifbarrierstoentryarelowandthereispotentialcompetition. SummaryforCharacteristicsofMarket PerfectNumberofManyManyFewSingleBarrierstoNatureofsubstituteVerygoodGoodsubstitutesbutVerygoodsubstitutesordifferentiatedNogoodNatureofPricePrice,marketing,Price,marketing,PricingSometo SS4MicroeconomicsandR14Topicsindemandand R15ThefirmandmarketR16Aggregateoutput,price,andeconomicSS5MonetaryandFiscal,InternationalTradeandR18MonetaryandR19InternationaltradeandcapitalR20Currencyexchange Aggregateoutput,price,andeconomicGrossdomesticproduct Grossdomesticproduct(GDP)isthetotalmarketvalueofthefinalgoodsandservicesproducedinacountrywithinacertaintimeperiod.PurchasesofnewlyproducedgoodsandFinalgoodsandGoodsandservicesprovidedby ernment(e.g.theservicesprovidedby andthejudiciary,andgoodssuchasroadsandinfrastructureimprovements),valuedatcostto Thevalueofowner-occupiedhousing,justasincludingthevaluerentalhousing Grossdomesticproduct ThesaleorresaleofgoodsproducedinpreciousTransferpaymentsmadebythe retirement,andwelfarebenefits)Thevalueoflabornotsold(e.g.homeowner’srepairstohisown GDP GDPcanbecalculatedasthesumofallthespendingonnewlyproducedgoodsandservices,orasthesumoftheereceivedasaresultofproducingthesegoodsandservices.Undertheexpenditureapproach,GDPiscalculatedbysummingamountsspentongoodsandservicesproducedduringtheUndertheeapproach,GDPiscalculatedbysummingtheamountsearnedbyhouseholdsandcompaniesduringtheperiod,includingwagee,intereste,andbusinessprofits.Forthewholeeconomy,totalexpendituresandtotalemustbeequal,sothetwoapproachesshouldproducethesameresult. GDP ExpenditureApproach—summingthevaluesofallfinalgoodsandservicesproduced.summingtheadditionstovaluecreatedateachstageofproductionanddistribution.Anexampleofthecalculationforaspecificproductispresentedinthefollowingfigure. GDP ReceiptsatEachStage(€)Stage(€)ReceiptsoffarmerfromValueaddedbyReceiptsofmillerfromValueaddedbyReceiptsofbakerfromValueaddedbyReceiptsofretailerfromfinalValueaddedbyValueoffinaloutputTotalvalueadded=Totalecreated NominalandRealGDPandPer-CapitaReal NNominalGDPissimplyGDPaswehavedescribeditundertheexpendituresapproach:thetotalvalueofallgoodsandservicesproducedbyaneconomy,valuedatcurrentmarketprices.ForaneconomywithNdifferentgoodsandservices,wecanexpressnominalGDPas:NNN=(priceofgoodiinyeart) tyofgoodiproducedinyear NominalandRealGDPandPer-CapitaRealGDP联系电RealGDPiscalculatedrelativetoabaseyear.Byusingbase-yearandcurrent-yearoutput ties,realGDPgrowthreflectsonlyincreasesintotaloutput,notsimplyincreases(ord