英文版產(chǎn)業(yè)經(jīng)濟學(xué)教程第4章價格歧視.ppt

Chapter4Pricediscrimination ECNUOrientalRealEstateCollege 4 1Definition Aprevalentmarketingskillandeconomicphenomena preferentialpriceorquantitydiscount eg Sometimespeoplewillthinkthatiffirmschargedifferentpriceondifferentconsumersforthesamegoods itmeanspricediscrimination Butthisunderstandingisincomplete Inmuchcase discretepricemaybeonlyreflecttrafficcostandsalescostfee Andincertaincase universalpricemeansdiscriminationonthecontrary fixedfeeinbuseg Pricediscriminationmeansonefirmsalestheidenticalgoodstodifferentconsumerswithdifferentnetprice Philips 1983 Netprice subtractproductdifferencefromgoodsprice Ifpricedifferentiationjustreflectsthecostdifferenceofsupplyingtodifferentconsumers wedeempricediscriminationdoesn texist Ratiotest Harrypotter inpainlypackededitionvs deluxeedition eg Atthesametime wecan tsayprovidingdifferentqualitygoodstodifferentconsumersmeansnodiscrimination Reasonofprovidingserviceindifferentquality suchasclassedcabininaircraftsandtrains partlyistogetconsumerssurplusbysegmentingconsumersintodifferentgroupsTheconceptof identical goods BMWinUSAisthesametoinGerman Generalequilibriumtheoristmaypointoutwithsomeexcuse goodsdeliveredindifferenttime differentlocationanddifferentstateordifferentqualityisdifferentgoods soscopeofpurepricediscriminationisverylimited Conditionsofpricediscrimination 1 firmsmusthasmarketpower Weoftenconfineitinmonopolyoroligopolymarket onlywhenfirmscanpricehigherthanmarginalcost cantheychargedifferentpriceondifferentconsumers LocayandRodriguez 1992 competitivefirmsispossibletopracticepricediscrimination ifconsumerspurchaseingroupunit 2 theabilityofeffectivemarketsegmentation 3 ensureofnoarbitrage Marketsegmentation Canwefindarightwaytoconductmarketsegmentation theresultmustberelatedtopriceelasticityandWTP willingtopay statusgenderageLocationtimeusePurchasingamount Kindsofarbitrages Possibilityofpricediscriminationisrelatedwithpossibilityofarbitrage Onekindofarbitrageisrelatedwithtransferabilityofgoods Iftransactioncostislow pricediscriminationwillencounterarbitrage namelylow priceconsumerswillbuyforresellingtohigh priceconsumers Transactioncostprovidesonecluetofeasibilityofpricediscrimination Absolutearbitrageornoarbitrageisonlytwoextremecase Generally somelimitedarbitragewilloccurs itdependsonrelativecostandincome Theotherkindofarbitrageisrelatedwithtransferabilityofdifferentconsumepackagesorbundlesprovidedtoconsumers Thatnotmeansphysicaltransferofgoodsamongconsumers Thatmeansfirmstrytomakeeverybuyerreallyselectconsumepackagedesignedforhim notforothers Incentivecompatibilityandself selection Influenceofarbitrage Influenceoftwokindsofarbitrageisdifferent Transferabilityofgoodsisinclinedtopreventdiscrimination Transferabilityofdemandmaycausefirmsincreasediscrimination Threekindsofpricediscrimination Perfectpricediscrimination suppliersgetallconsumersurplusinconditionofholdingperfectinformationofwillingpayment Second degreepricediscrimination suppliersextractconsumersurplusincompletelyusingself selectionwheninformationofindividualpreferenceisincomplete Third degreepricediscrimination Marketsegmentationusingdirectinformationaboutdemandsuchasage professionandlocationetc andsetdifferentpriceforeachgroup 4 2Perfectpricediscrimination simplestcase singleconsumer orsomeidenticalconsumers hasoneunitofdemand Monopolymakepriceequaltoreserveprice gettingallconsumersurplus Aclassicalexample adoctorisalittlevillagesimilarwitheverybodyinthereandtheireconomicinformation Heestimateshowmucheveryoneiswillingtopayforandthenchargeforthatamount Anothercase airlinecompanypayforeachaircraftindifferentprice 2 Complexcase assumption nconsumersholdthesamedemandcurve andmonopolyknowaboutit q D p n soD p nqTgrossofconsumers paymentTwopricingprojects linearpricingandtwoparttariffLinearpricing T pqTwoparttariff T A pq Profitmaximization Inlinearpricing monopolyprice p Twoparttariff setasnetconsumersurplusincompetitivepricep set licensefee A sopricingprojectasbelowT q Profitcompare Monopolypricing Twoparttariff 0 Ifq 0 Ifq 0 Profitcompare D MC A B C ABC Obviously alltheconsumersurplusisgrabbedintwoparttariff 3 Universalcase Assumption consumersholddifferentdemandcurves andmonopolyknowaboutthem Optimalproject setp andaskeachconsumerpayitsnetsurplusas licensefee namelyProblemofinformationrevealwhenconsumerhasunitdemandandsupplieronlyknowdistributionofestimationamongthembutnoabouteveryone sestimation itwillsetsingleprice meansnopricediscrimination HowtomakePerfectpricediscrimination Infactit saquestionofinformationemergingCompretivelyusecouponoraccumulatedconsumingvolumesAuctionorbidPricinginbindBargainingdirectly 優(yōu)惠券的使用 JournalofMarketingResearch 1978 表中條目是有使用優(yōu)惠券傾向的全職主婦購買商品的比例括號中的數(shù)字表示所表示比例的抽取樣本中人數(shù) 4 3Third degreepricediscrimination Multi market assumption Monopolycansegmentconsumersinsomegroupsaccordingtosomeexogenousinformation andknowabouteachoftheirdemandcurves Noarbitrageamonggroups andmonopolycan tpractisepricediscriminationinonegroup Aspecialexampleofmultipleproductsmonopolypricing independentdemandandinterdependentcost Howtopreventarbitrage 持卡 憑證擔保 轉(zhuǎn)售限制 尤其是對于中間商 摻雜交易費用合約垂直一體化專欄 航空公司如何防止套利 Profitmaximization GeneraldemandProfitfunctionAccordingtoInverseelasticityrule Lernerindex ineverymarketshouldexistsOptimalpricingmeanssettingcomparativelyhighpriceinmarketwithlowerelasticity MR1 D1 MR2 D2 MC p1 p2 Q1 Q2 Welfarecompare CompareitwiththeresultofuniformpricingAssumethatscalerewardfixed Cisconstant Profitandsurplus Incaseofpricediscrimination priceinmarketiispi profitasbelowGeneralconsumersurplusisIncaseofuniformpricing priceis salesamountinmarketIis profitasbelowGeneralconsumersurplusis Differenceonwelfare GeneraldifferenceequalstochangeofsurplusplusprofitTosetuplimitanddownlimit makeFunctionofNSWisconvexfunctionofmarketprice andS p D p accordingtoLagrangemediantheory wecangetSo ifpricediscriminationcannotincreasesalesvolume welfarewillbereduced Thatisthenecessaryconditionofexistenceofpricediscriminationinthesocialangle Conclusion Generally thewelfareeffectofthethird degreepricediscriminationisuncertain Itdependsonthecomparebetweenlossoflow elasticitycomparisonandgainofhigh elasticityconsumersandsuppliers Oneofthecentralquestioninpolicyisitsinfluencetoincomedistribution Pricediscriminationtransfersbenefitoflow elasticityconsumerspartlytohigh elasticityconsumersandsuppliers Itmaybenotappropriate butasweknow low elasticityconsumersaregenerally notalways richergroup 三級價格歧視實例1 三級價格歧視實例2 迪斯尼世界門票價格 2006 4 4Second degreepricediscrimination Assumption consumerdemandisheterogeneous Ifmonopolyknowabouttastesofallconsumers itcanmakeperfectpricediscriminationthroughprovidingpersonalconsumepackagesorbundles Butmonopolygenerallycannotclassifyconsumersaccordingtosomeexplicitinformation anditcanprovideamenuforselection Thenpossibilityofarbitragemustbeconsidered namelyconsumersbelongingtoonegroupmaychooseconsumepackagedesignedforothergroups Therestrictionofself selectionorincentive compatible 4 4 1indirectpricediscriminationbasedontime 航空公司基于訂票時間的價格歧視 p 起飛時間 預(yù)售時間 票價與提前訂票時間的關(guān)系 提前訂票時間 2 3天 4 4 2Indirectpricediscriminationbasedonquality ProductlineswithdifferentqualitystatusDifferentkindsofconsumers highvaluetype lowvaluetypeCommonstrategy harmed goods IBM Sony Intel p Productstatus 400 350 300 600 486SX 486 質(zhì)量歧視的三個決策 廠商應(yīng)該確定幾種不同的等級 實踐表明 三個而不是兩個等級是最優(yōu)的 各個等級水平如何選擇 如何為每個等級的產(chǎn)品制定相應(yīng)的價格 參與約束 激勵相容約束 例 參考價格對高價位產(chǎn)品的影響 4 4 3Indirectpricediscriminationbasedonquantity quantitydiscount taxifeeelectricpowerusePackagestrategy quantity priceportfolio 英國移動通信公司的二部定價套餐 此外還有 移動的動感地帶短信套餐等 4 5Comparisionamongseveralmethodsinnonlinearpricing Two parttariff T q A pq providesamenuofconsumebundlesinaline Generallythelinedoesnotpassorigin Simplicityisitsprimaryattraction andsometimesitdependsonpossibilityoflimitedarbitrage Fullarbitrageisprevented namelyonlyonebuyerpaysforfixedfeeA andthenresalegoodstootherconsumers Notice actuallytwo parttariffcorrespondstoquantitydiscount averagepricedecreasewithincreaseofconsumequantity Profitandwelfare Assumption consumersreferenceasbelowU V 0 0 V q 0 V q 0 isaconstantoftaste differentinperson V isuniformtoeveryone Alsothesecanbeexplainedinthesamepreferenceofconsumersbutwithdifferentincomelevel Compareamongcaseofperfectdiscrimination monopolypricingandtwo parttariff V q TiftheypayTandconsumeq 0iftheydonotbuy Asimplemodel Twokindsofconsumers proportionoftasteparameterbeing 1is proportionoftasteparameterbeing 2is1 Assumethat 2 1 monopolyproduceinfixedcostc andc 1 2 forsimplicity assumesoV q 1 q Utilityfunction Notice fixedcostonlyinfluencethedecisionofbuyingornot Onceconsumersdecidetobuy itisoutofconsider Consumerutilitymaximization U iV q pqFirst ordercondition iV q pAccordingtoassumptionbefore i 1 q pSo demandfunctioniseducedasq Di p 1 p iNetconsumersurplusis Generaldemandfunction Inthiscase consumersurplusisNoticethat and 2typeconsumersalwaysholdhighersurplus Make asharmonicmeanof 1and 2Thengeneraldemandinpricepis 2 1 p P1 c D1 D2 S2 p S1 p Case1 perfectpricediscrimination Assumethatmonopolycanobserve idirectly Thenitcansetmarginalpriceasp1 c andsetpersonalfixedfeeManufacturer smonopolisticprofitisLeavedistributionquestionoutofaccount welfarehereisoptimal Case2 Monopolypricing Assumethatconsumershavecompletearbitrage sothatmonopolycanonlysetuniformprice T q pqProfitis p c D p andD p 1 p MonopolypriceisMonopolisticprofitisHereweassumethatmonopolydecidestoprovidegoodstotwokindsofconsumers Itneed c 2 2 1 or islargeenough Case3 Two parttariff Assumealsothatmonopolyprovidesgoodstotwokindsofconsumers Setmarginalpricep Maximalfixedfeethatcanmake 1typeconsumersbuygoodsisA S1 p Then 2typeconsumerswillpurchase becauseSoprofitfunctionofmonopolyisPriceofprofitmaximizationisSimply wecanseethatprofitoftwo parttariffisasgoodasinlinearpricingatleast thelatecanbeseenasthespecialcaseoftheformer Comparisoninwelfareeffect It ssimpletojudgethatAndalso inthecaseofsupplyingtwokindsofconsumersatthesametime marginaloftwo parttariffisbetweencompetitivepriceandmonopolyprice namelyNotice welfareundertwo parttariffishigherthaninlinearpricing becausemarginalpricedecreasingwillbringpurchasingmorebytwokindsofconsumers sodistortionisreduced Tomonopoly itcanmakeuplossbyfixedfeewhendecreasingprice Sofixedfeewillinducemonopolydecreasepricesothatwelfareisgained Conclusion Wecanmakeamorecomplexprojecttogetmoreprofitthroughcompletenonlinearpricing processomitted Conclusion1 low demandconsumersdonotgetnetsurplus whilehigh demandconsumerscangetpositivenetsurplus Conclusion2 effectiverestrictiontopersonalarbitragewillpreventhigh demandconsumersbuylow demandbundles Conclusion3 high demandconsumersbuysociallyoptimalquantity andlow demandconsumersbuyquantitylowerthanoptimalquantity 4 6Qualitydiscrimination Monopolycanalsopractisediscriminationthroughprovidingdifferentqualitygoodstodifferenttastyconsumers Itisverysimilartoquantitydiscrimination Assumethatconsumershaveunitd