价格理论

[TheoryofPrice][Demand]DemandandWantDemandandQuantityDemanded————[LawofDemand][DemandSchedule]QdP7001600250034004300520061007654321P0100200300400500600700Qd7[DemandCurve][DemandFunction]Qd=800100Pdd————011bPaQd−=0pbdPdQd−=()0,0fba≥αλ−=PQd01p−−−=ααλPdPdQd()0,0ffλα,[Substitute][Complement][NormalGoods][InferiorGoods][Preference][]·P0QdP1P2Qd2Qd1ABP0QdP1Qd1Qd2d1d2A1A2[Supply]SupplyandWant]SupplyandQuantitySupplied————12[LawofSupply][SupplyCurve][SupplyFunction]Qs=400+200Pss654321P0100200300400500600700Qd7800[SupplySchedule]QsP022003400460058006————0dPcQs+−=0fddPdQs=)0,0(fdc≥βλPQs=1−=ββλPdPdQs)0,0(ffλβ[Substitute][Complement]21P0QSPPQS2QS1ABSP0QSP1QS1QS2S1S2A1A213[Pricing]EquilibriumofSupplyandDemand——EquilibriumPrice——EquilibriumQuantity——Qs=400+200PssQdPQs600205003200400440030056002006800654321P0100200300400500600700Q7800Qd=800100PddEss654321P0100200300400500600700Q7800ddES1DQPS2P1Q1P2P3Q2Q3S3ssD1QPD2P1P3P2Q2Q3Q1D3LawofDemandandSupply——[][][]14[][][][1][2][PriceElasticityofDemand]Elasticity)(xfy=x—y—E—yxxyxxyyE•∆∆=∆∆=//ArcElasticityandPointElasticity121212121212121222yyxxxyxxxyyyxxxxyyyy++•∆∆=+∆+∆=+−+−=yxdxdyyxxyx•=•∆∆=→∆0limPriceElasticityofDemand——)(PfQd=ddEQP0//pdddddQPPQPPQQE•∆∆=∆∆=0lim0pdddPdQPdPdQQPPQE•=•∆∆==→∆120=dE∞=dEPerfectlyInelasticPerfectlyElasticP0ddQdEd=0P0ddQdEd=1511=EdUnitElastic21pEdInelastic31fEdElasticP0a2ba2aabEd1Ed1Ed1QdPOQdBAC(OF,OG)FGαβEƒ?(P)PQdƒ?(P)CGOGƒ?(x)tgβtgαOBOAEGBCGCGOGGBOGBCACOFAFQd=ƒ(P)GBCG=·=·=====·===P0Qd(Qd=abP)U(OC,OD)DCQd=ƒ(P)BAE=UBUA1234VVPQd,Qd=f(P)ddPPydQddP+QdPdQddP+QdPyQddQdQddP+Qd16P0Qd\\\\\\////////////\\\\\\////////////Ed1321246ddP0Qd\\\\\\\\\\\\////////////////////////Ed1321246ddP0Qd\\\\\\//////////////////////////////Ed1123246ddQddQddPyQd+QdEdEd=1=0ddPEd10ddPEd10ddPPriceElasticityofSupply——EsQs/QsP/PQsPEs==yPPQsQs=a+bP(b0)dQsdPEs=yPPQs=bPPa+bP=bPPa+bPa=0Es=1a0Es1a0Es117b0b0CrossElasticityofDemandP0QsssEs1(a=0)aP1P2Q1Q2Qs=a+bPPOQsBAC(OF,OG)FGαEƒ?(x)PQsƒ?(x)CGOGƒ?(x)tgαCFFAECFFACGOGCGFACGCHQs=ƒ(p)OGFACGOGHBCBAE=BCAC=·=·===·=·===P0ssEs1(a0)aabQsP1P2Q1Q2Qs=a+bPP0ssEs1(a0)aQsP1P2Q1Q2Qs=a+bPQ=aPb(a0,b0)E=dQdPyPQ=(aP)=bbyPaPbP0QsEs1Es1Es11aQs=aPb(a0,b0)Esb——EQdx/QdxPy/PyQdxPyxy==Py1QdxyIncomeElasticityofDemand——18MEmQd/QdM/MQdMMQdEm==y[NormalGoods]Em0[InferiorGoods]Em0Em1Em1[ExertionofTheoryofPrice]ssssddddEEPQQPssssddddEEPQQPPQ0PEddssPQdQsQPQ0EPddssPQdQsPQ[PriceFloor]PQ0PEddssPFQdQsQQsQd=[MinimumWageLaw]WQ0WEddssMWQdQsQQsQd=19[CobwebTheory][1][2][CobwebModel]P0QddssEdQsdPdQddPQdt=f(Pt)Qst=f(Pt-1)Qdt=QstdQsdPdQddP=dQsdPdQsdPdQddPdQddPP0QssddE=dQsdPdQddPP0QssddEdQsdPdQddP1.[]2.[][]3.[][]4.5.6.7.8.9.10.11.12.13.20