大學(xué)MBA中級微觀講義(PPT 55頁).ppt

ChapterTwenty-Five,MonopolyBehavior壟斷行為,HowShouldaMonopolyPrice?,Sofaramonopolyhasbeenthoughtofasafirmwhichhastosellitsproductatthesamepricetoeverycustomer.Thisisuniformpricing.Canprice-discrimination（差別定價）earnamonopolyhigherprofits?,Structure,First-degreepricediscriminationSecond-degreepricediscriminationThird-degreepricediscriminationBundlingTwo-parttariff,TypesofPriceDiscrimination,1st-degree:Eachoutputunitissoldatadifferentprice.Pricesmaydifferacrossbuyers.2nd-degree:Thepricepaidbyabuyercanvarywiththequantitydemandedbythebuyer.Butallcustomersfacethesamepriceschedule.E.g.bulk-buyingdiscounts.,TypesofPriceDiscrimination,3rd-degree:Pricepaidbybuyersinagivengroupisthesameforallunitspurchased.Butpricemaydifferacrossbuyergroups.E.g.,seniorcitizenandstudentdiscountsvs.nodiscountsformiddle-agedpersons.,First-degreePriceDiscrimination,Eachoutputunitissoldatadifferentprice.Pricemaydifferacrossbuyers.Itrequiresthatthemonopolistcandiscoverthebuyerwiththehighestvaluationofitsproduct,thebuyerwiththenexthighestvaluation,andsoon.,First-degreePriceDiscrimination,p(y),y,$/outputunit,MC(y),Sellthethunitfor$,First-degreePriceDiscrimination,p(y),y,$/outputunit,MC(y),Sellthethunitfor$Lateronsellthethunitfor$,First-degreePriceDiscrimination,p(y),y,$/outputunit,MC(y),Sellthethunitfor$Lateronsellthethunitfor$Finallysellthethunitformarginalcost,$,First-degreePriceDiscrimination,p(y),y,$/outputunit,MC(y),Thegainstothemonopolistonthesetradesare:andzero.,Theconsumersgainsarezero.,First-degreePriceDiscrimination,p(y),y,$/outputunit,MC(y),Sothesumofthegainstothemonopolistonalltradesisthemaximumpossibletotalgains-to-trade.,PS,First-degreePriceDiscrimination,p(y),y,$/outputunit,MC(y),Themonopolistgetsthemaximumpossiblegainsfromtrade.,PS,First-degreepricediscriminationisPareto-efficient.,First-degreePriceDiscrimination,First-degreepricediscriminationgivesamonopolistallofthepossiblegains-to-trade,leavesthebuyerswithzerosurplus,andsuppliestheefficientamountofoutput.,Examplesof1st-degreePriceDiscrimination,AuctionofantiqueCarsalesFinancialaidinuniversitiesMaynotbepracticaldonotknowwillingnesstopaytoocostly,Non-linearpricingUnitpricedependsonquantitypurchasedBulkdiscountSettingAsellerdoesnotknowthewillingnesstopaybyeachindividualbuyerConsumersmarginalwillingnesstopaydeclineswithquantity,Second-degreePriceDiscrimination,SettingauniformpriceisnotoptimalToohighapricewouldlosehighvolumeconsumer.Toolowapricewouldlostrevenuefromlowvolumeconsumer.Cokeexample.Mechanism：Setpricefordifferentvolumestoletconsumersidentifythemselves,Second-degreePriceDiscrimination,TwoconsumersPerson1haslowwillingness-to-payPerson1hashighwillingness-to-payAssume0MC,AnExample,A,quantity,$/outputunit,x10,x20,C,B,ChargeAforx10hopingtogetperson1ChargeA+B+Cforx20hopingtogetperson2Butperson2isbetteroffbuyingx10andreceivingacs=BFailtoletconsumersself-selectthemselvesProfit=2ACanalternativelychargeA+Cforx20toidentifyperson2profit=2A+C,Second-degreePriceDiscrimination,A,quantity,$/outputunit,x10,x20,C,B,Reducex10soAisreducedbyalittlebutCcanbeincreasedbyalot。Persons1and2arestillidentifiedProfitishigher,Second-degreePriceDiscrimination,A,quantity,$/outputunit,MC(y),x1m,x20,C,B,Profitismaximizedatx1m,Second-degreePriceDiscrimination,2nd-degreediscriminationcanalsooccurinthedimensionofqualityDifferentpricesfordifferentseatsinatheaterDifferentpricesforeconomyclassvs.businessclassseatsinairplanes,Second-degreePriceDiscrimination,Third-degreePriceDiscrimination,Pricepaidbybuyersinagivengroupisthesameforallunitspurchased.Butpricemaydifferacrossbuyergroups.Qualityofgoodsisthesameacrossgroups.Canidentifygroupsbutnofurtheridentificationwithinthatgroup.,Third-degreePriceDiscrimination,Amonopolistmanipulatesmarketpricebyalteringthequantityofproductsuppliedtothatmarket.Sothequestion“Whatdiscriminatorypriceswillthemonopolistset,oneforeachgroup?”isreallythequestion“Howmanyunitsofproductwillthemonopolistsupplytoeachgroup?”,Third-degreePriceDiscrimination,Twomarkets,1and2.y1isthequantitysuppliedtomarket1.Market1sinversedemandfunctionisp1(y1).y2isthequantitysuppliedtomarket2.Market2sinversedemandfunctionisp2(y2).,Third-degreePriceDiscrimination,Forgivensupplylevelsy1andy2thefirmsprofitisWhatvaluesofy1andy2maximizeprofit?,Third-degreePriceDiscrimination,Theprofit-maximizationconditionsare,Third-degreePriceDiscrimination,and,so,theprofit-maximizationconditionsare,and,Third-degreePriceDiscrimination,MR1(y1)=MR2(y2)saysthattheallocationy1,y2maximizestherevenuefromsellingy1+y2outputunits.E.g.ifMR1(y1)MR2(y2)thenanoutputunitshouldbemovedfrommarket2tomarket1toincreasetotalrevenue.,Third-degreePriceDiscrimination,Themarginalrevenuecommontobothmarketsequalsthemarginalproductioncostifprofitistobemaximized.,Third-degreePriceDiscrimination,MR1(y1),MR2(y2),y1,y2,y1*,y2*,p1(y1*),p2(y2*),MC,MC,p1(y1),p2(y2),Market1,Market2,MR1(y1*)=MR2(y2*)=MC,andp1(y1*)p2(y2*).,Third-degreePriceDiscrimination,Recallthat,and,Inwhichmarketwillthemonopolistsetthehigherprice?,But,Third-degreePriceDiscrimination,So,Therefore,onlyif,Themonopolistsetsthehigherpriceinthemarketwheredemandisleastown-priceelastic.,Examplesof3rd-degreePriceDiscrimination,Discountstostudents,seniorcitizensBusinesstravelersandvacationersGovernmentandprivate-sectorpurchasersCouponsandrebatesFirst-runmoviesanddollarmovieHardcoverbooksandpaperbackbooks,Bundling,Willingnesstopayforsoftwarecomponents,TwoMarketingPolicies,Sellseparately:Wordprocessor:p=100,revenue=200Speadsheet;p=100,revenue=200BundlingSetp=220forthebundleRevenue=440,Two-PartTariffs,Atwo-parttariffisalump-sumfee,p1,plusapricep2foreachunitofproductpurchased.Thusthecostofbuyingxunitsofproductisp1+p2x.,Two-PartTariffs,Shouldamonopolistpreferatwo-parttarifftouniformpricing,ortoanyoftheprice-discriminationschemesdiscussedsofar?Ifso,howshouldthemonopolistdesignitstwo-parttariff?,Two-PartTariffs,p1+p2xQ:Whatisthelargestthatp1canbe?A:p1isthe“entrancefee”sothelargestitcanbeisthesurplusthebuyergainsfromenteringthemarket.Setp1=CSandnowaskwhatshouldbep2?,Two-PartTariffs,p(y),y,$/outputunit,MC(y),Shouldthemonopolistsetp2aboveMC?,Two-PartTariffs,p(y),y,$/outputunit,CS,Shouldthemonopolistsetp2aboveMC?p1=CS.,MC(y),Two-PartTariffs,p(y),y,$/outputunit,CS,Shouldthemonopolistsetp2aboveMC?p1=CS.PSisprofitfromsales.,MC(y),PS,Two-PartTariffs,p(y),y,$/outputunit,CS,Shouldthemonopolistsetp2aboveMC?p1=CS.PSisprofitfromsales.,MC(y),PS,Totalprofit,Two-PartTariffs,p(y),y,$/outputunit,Shouldthemonopolistsetp2=MC?,MC(y),Two-PartTariffs,p(y),y,$/outputunit,Shouldthemonopolistsetp2=MC?p1=CS.,CS,MC(y),Two-PartTariffs,p(y),y,$/outputunit,Shouldthemonopolistsetp2=MC?p1=CS.PSisprofitfromsales.,MC(y),CS,PS,Two-PartTariffs,p(y),y,$/outputunit,Shouldthemonopolistsetp2=MC?p1=CS.PSisprofitfromsales.,MC(y),CS,Totalprofit,PS,Two-PartTariffs,p(y),y,$/outputunit,Shouldthemonopolistsetp2=MC?p1=CS.PSisprofitfromsales.,MC(y),CS,PS,Two-PartTariffs,p(y),y,$/outputunit,Shouldthemonopolistsetp2=MC?p1=CS.PSisprofitfromsales.,MC(y),CS,Additionalprofitfromsettingp2=MC.,PS,Two-PartTariffs,Themonopolistmaximizesitsprofitwhenusingatwo-parttariffbysettingitsperunitpricep2atmarginalcostandsettingitslump-sumfeep1equaltoConsumersSurplus.,Two-PartTariffs,Aprofit-maximizingtwo-parttariffgivesanefficientmarketou