中级微观经济学（中山大学）.PPT.ppt

MICROECONOMICSClassroomLectureNotes(3credits,asof2004),basedonHalR.VariansIntermediateMicroeconomics,SixthEdition,referringtoPindyckandRubinfeldsMicroeconomics,FourthEdition.,Chapter0,Economics,Thesourceofalleconomicproblemsisscarcity.,Problemoftrade-off,andchoice.Economics,asawayofthinking,asadismalscience.Problems-solutions-hiddenconsequences.,Maindecision-makingagents:,1individuals(household),2firms,and3governments.,Objectsofeconomicchoicearecommodities,includinggoodsandservices.,Maineconomicactivities:,Consumption,Production,andExchange.,Microeconomicsandmacroeconomics:,toshowthemarketmechanism(theinvisiblehand),tosupplementit.,Thecircularflowofeconomicactivities.,productmarketfactormarket,Theproductmarketandthefactormarket.,Themarketrelationismutualandvoluntary.Positiveissuesandnormativeissues.,Marginalanalysis,RelationsbetweenTotalmagnitudes,Averagemagnitudes,andMarginalmagnitudes.,1,MMistheslopeoftheTMcurve;2,AMistheslopeoftherayfromtheorigintothepointattheTMcurve;,TM,MM(x*),AM(x*),x*,x,3,TMincreasing(decreasing)ifandonlyifMM0(MMAM(MM0.ThusboththeincomeoffercurvesandtheEngelcurvesareallraysthroughtheorigin.,Example:Quasilinearpreferencesleadtovertical(horizontal)incomeoffercurvesandvertical(horizontal)Engelcurves.,Chapter8,SlutskyEquation,Howtheoptimummoveswhenthepriceofagoodchanges?,Decomposition:thetotaleffect=thesubstitutioneffect+theincomeeffect.p139,Thepivotgivesthesubstitutioneffect,theshiftgivestheincomeeffect.P103andp137,Slutskyidentity,pivotingthebudgetlinearoundtheoriginalchoice.Fig.Hicksdecomposition,pivotingthebudgetlinearoundtheindifferencecurve.Fig.,Chapter9,BuyingandSellingforaconsumerwithanendowment,x1,x1,x2,p1,1,1,Netandgrossdemands,netsupply.Offercurveanddemandcurve.p164,Laborsupplyp174,$,LeisureR,Labor,W,Leisure,E,Chapter10,IntertemporalChoice,Supposeforexampleina3-periodmodel,theconsumptionisckandtheinterestrateisrkinperiodk,thenthepresentvalueoftheconsumptionsisc1+c2/(1+r1)+c3/(1+r1)(1+r2).p190,Chapter12,Uncertainty,Utilitiesandprobabilities.,Expectedutilityfunctions,orvonNeumann-Morgensternutilityfunctions.Theyareindifferentuptoanypositiveaffinetransformation.(affinetransformation:y=a+bx).,Riskaversionandriskloving.,Concavevsconvexutility.,Thesecondderivatives.,$,$,U,U,Chapter14,Consumerssurplus,123456,p,r1,r2,r3,r4,r5,r6,ConsumersSurplusp250,消费者得益,总收益,Producerssurplusp259,Producerssurplus,Supplycurve,Q,P*,Q*,P,Q,Supplycurve,Changeinproducerssurplus,R,T,Q,Q,P,P,P,Thewater-diamondparadox,PdPw,Q,Calculatinggainsandlosses,Changeinconsumerssurplus,B,T,Chapter15MarketDemand,Onecanthinkofthemarketdemandasthedemandofsome“representativeconsumer”.,Addingupdemandcurves:Thehorizontalsummationprinciple.,+,=,Horizontalsummation,PRICE,DEMANDCURVE,D(p),QUANTITY,Itisthesumoftheindividualdemandcurve,Themarketdemandcurve,Thepriceelasticityofdemand:=(q/q)/(p/p)=(p/q)/(p/q),or=(dq/q)/(dp/p)=(p/q)/(dp/dq)=slopeofray/slopeofcurve.,Agoodhasanelastic(inelastic,unitary)demandif|1(|1,=1,f(tx)(1/2,p=0,1ifq=1/2,0ifq1/2,q=0,1ifp=1/2,1ifp1/2.,q1,1p,N,0,Methodofresponsefunctions:TheintersectionsofresponsefunctionsgiveNashequilibria(p*,q*)=(1/2,1/2)inexample)NashTheorem:Thereisalwaysa(maybe“mixed”)Nashequilibriumforanyfinitegame,Sequentialgames.Gamesinextensiveformversusinnormalform.,BattleofSexesagain,Boy,Girl,Ballet,Ballet,Ballet,Soccer,Soccer,Soccer,(1,2),(-1,-1),(0,0),(2,1),StrategiesasPlansofActions.Boysstrategies:Ballet,andSoccer.GirlsStrategies:Balletstrategy;Soccerstrategy;Strategytofollow;andStrategytooppose.,Chapter28Exchange,Partialequilibriumandgeneralequilibrium,Edgeworthboxp497,Apureexchangemodeloftwogoods,twoconsumerswithfixedendowmentsw.,Regionofmutualadvantages.Paretosetandthecontractcurve.Bargainingforrelativeprices.Grossdemandx(p),Netorexcessdemandz(p)=x(p)-w(p).,PersonB,PersonA,xA1,wA1,Endowment,wA2,xA2,GOOD2,GOOD1,xB1,wB1,xB2,wB2,M,Endowment,PersonBsindifferencecurve,AParetoefficientallocation,PersonAsindifferencecurve,Contractcurve,PersonA,GOOD1,GOOD2,PersonB,Fromdisequilibriumtothecompetitiveequilibrium.Whichgoodistoocheap?Offercurveapproach.Theexistenceproblemofequilibrium.,Asind,curves,Bsind.curves,Asoffercurve,Bsoffercurve,Good1isToocheap,Equilibriumprice,W,E,Chapter29Production,TheRobinsonCrusoeeconomy,Productionfunction,Indifferencecurves,Labor,L*,C*,Coconuts,Productionpossibilitiesset,F*,C*,COCNUTS,FISH,PRODUCTIONPOSSIBILITIESSET,SLOPE=MARGINALRATEOFTRANSFORMATION,(Twooutputscase),TradeleadstoSeparationofprod.andcoms.(P/C),Productionspecialization(AP),andWealthimprovement(AC).,A,P,C,Heckscher-Ohlintheoryoninternationaltrade,undermanyidealizationassumptions.,*Costsofexchange.*Pricedifferencebetweensellingandbuying.Fig.*GATTandWTO.,Chapter30Welfare,Thesocialpreference.Twokindsofvoting:majority,andrank-order.,Thesocialwelfarefunction.,Benthamite:W(u1,un)=a1u1+anun.Rawlsian:W(u1,un)=minu1,un.,Threerequirementsonasocialdecisionmechanism:,1,Itshouldbecomplete,reflexive,andtransitive;2,IfeveryoneprefersXtoY,thenthesocietyshouldpreferXtoY;3,ThepreferencesbetweenXandYshoulddependonlyonhowpeoplerankXversusY,andnotonhowtheyrankotheralternatives.,ArrowsImpossibilityTheorem,Ifasocialdecisionmechanismsatisfiesproperties1,2,and3,thenitmustbeadictatorship:allsocialrankingsaretherankingsofoneindividual.,Chapter31,Externalities,Thelackofmarketsforexternalitiescausesproblems.,Withexternalities,themarketwillnotnecessarilyresultinaParetoefficientprovisionofresources.,However,someothersocialinstitutionscanmimicthemarketmechanism.,Themodelofsmokersandnonsmokers(showingexcellentanalysistechniques).,PersonA,PersonB,SMOKE,MONEY,Asindifferencecurves,PossibleequilibriumX,Possiblee