北大經(jīng)院：Chapter-33-總供給與總需求-2016-05-15課件

1第三十三章總需求與總供給AggregateDemandandAggregateSupply2ButThis“LongRun”isamisleadingguidetocurrentaffaires.“Inthelongrun”wearealldead.Economistssetthemselvestooeasy,toouselessataskifintempestuousseasonstheycanonlytellusthatwhenthestormislongpasttheoceanisflatagain.

__JohnMaynardKeynesLongrunandshortrunLong-runmodelpotentialoutput,long-runinflationShort-runmodelcurrentoutput,currentinflationActualoutput=long-runtrend+short-runfluctuationTheshortrunisdefinedtobethelengthoftimeoverwhichthesedeviationsoccur.3

總需求與總供給

AggregateDemandandAggregateSupply

threekeyfactsaboutshort-runeconomicfluctuations.

howtheeconomyintheshortrundiffersfromtheeconomyinthelongrun.

howtousethemodelofaggregatedemandandaggregatesupplytoexplaineconomicfluctuations.

howshiftsineitheraggregatedemandoraggregatesupplycancauseboomsandrecessions.45短期經(jīng)濟(jì)波動(dòng)

Short-RunEconomicFluctuations經(jīng)濟(jì)活動(dòng)年復(fù)一年地波動(dòng)Economicactivityfluctuatesfromyeartoyear.在大多數(shù)年份里，物品與服務(wù)的生產(chǎn)是上升的Inmostyearsproductionofgoodsandservicesrises.在過(guò)去50年，平均來(lái)說(shuō)，美國(guó)經(jīng)濟(jì)的生產(chǎn)每年增長(zhǎng)約3個(gè)百分點(diǎn)。Onaverageoverthepast50years,productionintheU.S.economyhasgrownbyabout3percentperyear.在一些年份，正常的增長(zhǎng)沒(méi)能出現(xiàn)，導(dǎo)致了衰退。Insomeyearsnormalgrowthdoesnotoccur,causingarecession.

6短期經(jīng)濟(jì)波動(dòng)

Short-RunEconomicFluctuations衰退是實(shí)際GDP下降、收入減少、失業(yè)上升的時(shí)期A(yíng)recessionisaperiodofdecliningrealGDP,fallingincomes,andrisingunemployment.蕭條是嚴(yán)重的衰退Adepressionisasevererecession.7衰退RecessionsRealGDP

實(shí)際GDP:Figure31-1Billionsof1992Dollars19651970197519801985199019952,5003,0003,5004,0004,5005,0005,5006,0006,500$7,000RealGDP短期經(jīng)濟(jì)波動(dòng)一瞥ALookAtShort-RunEconomicFluctuations8Recessions(b)InvestmentSpending投資支出Billionsof1992Dollars3004005006007008009001,000$1,100Investmentspending1965197019751980198519901995短期經(jīng)濟(jì)波動(dòng)一瞥ALookAtShort-RunEconomicFluctuations9Recessions(c)UnemploymentRate失業(yè)率Unemploymentrate0246810121965197019751980198519901995PercentofLaborForce短期經(jīng)濟(jì)波動(dòng)一瞥ALookAtShort-RunEconomicFluctuations10衰退短期經(jīng)濟(jì)波動(dòng)一瞥：中國(guó)ALookAtShort-RunEconomicFluctuations:China

實(shí)際GDP資料來(lái)源：《中國(guó)國(guó)內(nèi)生產(chǎn)總值核算歷史資料，1952－1995》，《中國(guó)統(tǒng)計(jì)年鑒》以及作者計(jì)算。11衰退短期經(jīng)濟(jì)波動(dòng)一瞥：中國(guó)ALookAtShort-RunEconomicFluctuations:China(b)投資支出12中國(guó)：GDP、工業(yè)生產(chǎn)總值、固定資產(chǎn)投資年增長(zhǎng)率的波動(dòng)13關(guān)于經(jīng)濟(jì)波動(dòng)的三個(gè)關(guān)鍵事實(shí)ThreeKeyFactsAboutEconomicFluctuations經(jīng)濟(jì)波動(dòng)是不規(guī)則和不可預(yù)測(cè)的。Economicfluctuationsareirregularandunpredictable.經(jīng)濟(jì)當(dāng)中的波動(dòng)常常被稱(chēng)作經(jīng)濟(jì)周期（或譯商業(yè)周期）

Fluctuationsintheeconomyareoftencalledthebusinesscycle.Trashindicator(TheChicagoTribune)14關(guān)于經(jīng)濟(jì)波動(dòng)的三個(gè)關(guān)鍵事實(shí)ThreeKeyFactsAboutEconomicFluctuations大多數(shù)宏觀(guān)經(jīng)濟(jì)變量一起波動(dòng)。Mostmacroeconomicvariablesfluctuatetogether.大多數(shù)衡量某種收入或生產(chǎn)的宏觀(guān)經(jīng)濟(jì)變量幾乎同時(shí)波動(dòng)。Mostmacroeconomicvariablesthatmeasuresometypeofincomeorproductionfluctuatecloselytogether.雖然許多宏觀(guān)經(jīng)濟(jì)變量一起波動(dòng)，他們波動(dòng)的幅度并不同。Althoughmanymacroeconomicvariablesfluctuatetogether,theyfluctuatebydifferentamounts.15關(guān)于經(jīng)濟(jì)波動(dòng)的三個(gè)關(guān)鍵事實(shí)ThreeKeyFactsAboutEconomicFluctuations隨著產(chǎn)出下降，失業(yè)上升。Asoutputfalls,unemploymentrises.實(shí)際GDP的變化和失業(yè)率的變化呈反向關(guān)系。ChangesinrealGDPareinverselyrelatedtochangesintheunemploymentrate.在衰退時(shí)期，失業(yè)大幅上升。Duringtimesofrecession,unemploymentrisessubstantially.16短期與長(zhǎng)期有何不同

HowtheShortRunDiffersFromtheLongRun大多數(shù)經(jīng)濟(jì)學(xué)家相信，古典理論描述了長(zhǎng)期而不是短期中的世界。Mosteconomistsbelievethatclassicaltheorydescribestheworldinthelongrunbutnotintheshortrun.貨幣供給的變化影響長(zhǎng)期中的名義變量而非實(shí)際變量Changesinthemoneysupplyaffectnominalvariablesbutnotrealvariablesinthelongrun.貨幣中性（二分法）的假設(shè)在研究經(jīng)濟(jì)的逐年變化時(shí)是不恰當(dāng)?shù)腡heassumptionofmonetaryneutralityisnotappropriatewhenstudyingyear-to-yearchangesintheeconomy.17經(jīng)濟(jì)波動(dòng)的基本模型

TheBasicModelofEconomicFluctuations我們用兩個(gè)變量來(lái)建立一個(gè)模型，以分析短期波動(dòng)。Twovariablesareusedtodevelopamodeltoanalyzetheshort-runfluctuations.以實(shí)際GDP衡量的經(jīng)濟(jì)當(dāng)中物品與服務(wù)的產(chǎn)出。Theeconomy’soutputofgoodsandservicesmeasuredbyrealGDP.以CPI或GDP平減指數(shù)衡量的整體價(jià)格水平。TheoverallpricelevelmeasuredbytheCPIortheGDPdeflator.18經(jīng)濟(jì)波動(dòng)的基本模型

TheBasicModelofEconomicFluctuations經(jīng)濟(jì)學(xué)家使用總需求與總供給模型來(lái)解釋經(jīng)濟(jì)活動(dòng)圍繞其長(zhǎng)期趨勢(shì)的短期波動(dòng)Economistusethemodelofaggregatedemandandaggregatesupplytoexplainshort-runfluctuationsineconomicactivityarounditslong-runtrend.19經(jīng)濟(jì)波動(dòng)的基本模型

TheBasicModelofEconomicFluctuations總需求曲線(xiàn)表示家庭、企業(yè)或政府在任一價(jià)格水平上想要購(gòu)買(mǎi)的物品與服務(wù)的數(shù)量。 Theaggregatedemandcurve

showsthequantityofgoodsandservicesthathouseholds,firms,andthegovernmentwanttobuyateachpricelevel.20經(jīng)濟(jì)波動(dòng)的基本模型

TheBasicModelofEconomicFluctuations總供給曲線(xiàn)表示企業(yè)在任一價(jià)格水平上生產(chǎn)和銷(xiāo)售的物品與服務(wù)的數(shù)量。Theaggregatesupplycurveshowsthequantityofgoodsandservicesthatfirmsproduceandsellateachpricelevel.21總需求與總供給……

AggregateDemandandAggregateSupply...EquilibriumOutput均衡產(chǎn)出QuantityofOutput產(chǎn)出數(shù)量PriceLevel價(jià)格水平0Equilibriumpricelevel均衡價(jià)格水平AggregateSupply總供給AggregateDemand總需求22總需求曲線(xiàn)

TheAggregateDemandCurveGDP（Y）的四個(gè)組成部分構(gòu)成了對(duì)物品與服務(wù)的總需求。ThefourcomponentsofGDP(Y)contributetotheaggregatedemandforgoodsandservices.Y=C+I+G+NX23總需求曲線(xiàn)

TheAggregate-DemandCurve...QuantityofOutputPriceLevel0AggregatedemandP1Y1Y2P22.…增加了物品與服務(wù)的需求數(shù)量increasesthequantityofgoodsandservicesdemanded.1.價(jià)格水平的下降A(chǔ)decreaseinthepricelevel...24為什么總需求曲線(xiàn)向下傾斜

WhytheAggregateDemandCurveIsDownwardSloping價(jià)格水平與消費(fèi)：財(cái)富效應(yīng)ThePriceLevelandConsumption:TheWealthEffect價(jià)格水平與投資：利率效應(yīng)ThePriceLevelandInvestment:TheInterestRateEffect價(jià)格水平與凈出口：匯率效應(yīng)ThePriceLevelandNetExports:TheExchange-RateEffect25價(jià)格水平與消費(fèi)：財(cái)富效應(yīng)

ThePriceLevelandConsumption:TheWealthEffect價(jià)格水平的下降使得消費(fèi)者感覺(jué)更加富有，這反過(guò)來(lái)鼓勵(lì)他們支出更多。Adecreaseinthepricelevelmakesconsumersfeelmorewealthy,whichinturnencouragesthemtospendmore.消費(fèi)支出的上升意味著對(duì)物品與服務(wù)更大的需求數(shù)量。Thisincreaseinconsumerspendingmeanslargerquantitiesofgoodsandservicesdemanded.26價(jià)格水平與投資：利率效應(yīng)

ThePriceLevelandInvestment:TheInterestRateEffect更低的價(jià)格水平增加了儲(chǔ)蓄，降低了利率，這鼓勵(lì)了對(duì)投資品的更大支出。Alowerpricelevelreducestheinterestrate,whichencouragesgreaterspendingoninvestmentgoods.投資支出的增加意味著物品與服務(wù)的需求數(shù)量更大。Thisincreaseininvestmentspendingmeansalargerquantityofgoodsandservicesdemanded.27價(jià)格水平與凈出口：匯率效應(yīng)

ThePriceLevelandnetExports:TheExchange-RateEffect當(dāng)美國(guó)的價(jià)格水平下降導(dǎo)致了美國(guó)的利率下降，實(shí)際匯率就會(huì)貶值，這又刺激了美國(guó)的凈出口。WhenafallintheU.S.pricelevelcausesU.S.interestratestofall,therealexchangeratedepreciates,whichstimulatesU.S.netexports.凈出口支出的增加意味著物品與服務(wù)的需求數(shù)量更大。Theincreaseinnetexportspendingmeansalargerquantityofgoodsandservicesdemanded.28總需求曲線(xiàn)為什么會(huì)移動(dòng)

WhytheAggregateDemandCurveMightShift總需求曲線(xiàn)向下傾斜，表示價(jià)格水平的下降增加了物品與服務(wù)總的需求數(shù)量。Thedownwardslopeoftheaggregatedemandcurveshowsthatafallinthepricelevelraisestheoverallquantityofgoodsandservicesdemanded.然而，在給定價(jià)格水平上，許多其他因素影響物品與服務(wù)的需求數(shù)量。Manyotherfactors,however,affectthequantityofgoodsandservicesdemandedatanygivenpricelevel.當(dāng)這些其他因素中的任一種發(fā)生改變，總需求曲線(xiàn)移動(dòng)。Whenoneoftheseotherfactorschanges,theaggregatedemandcurveshifts.29總需求曲線(xiàn)為什么會(huì)移動(dòng)

WhytheAggregateDemandCurveMightShift來(lái)自消費(fèi)的移動(dòng)ShiftsarisingfromConsumption來(lái)自投資的移動(dòng)ShiftsarisingfromInvestment來(lái)自政府購(gòu)買(mǎi)的移動(dòng)ShiftsarisingfromGovernmentPurchases來(lái)自?xún)舫隹诘囊苿?dòng)ShiftsarisingfromNetExports30總需求曲線(xiàn)的移動(dòng)

ShiftsintheAggregateDemandCurve...QuantityofOutputPriceLevel0Aggregatedemand,D1P1Y1D2Y231總供給曲線(xiàn)

TheAggregateSupplyCurve在長(zhǎng)期中，總供給曲線(xiàn)是垂直的。Inthelongrun,theaggregate-supplycurveisvertical.在短期內(nèi)，總供給曲線(xiàn)向上傾斜。Intheshortrun,theaggregate-supplycurveisupwardsloping.32長(zhǎng)期總供給曲線(xiàn)

TheLong-RunAggregateSupplyCurve在長(zhǎng)期中，經(jīng)濟(jì)的物品與服務(wù)的生產(chǎn)依賴(lài)于它的勞動(dòng)、資本與自然資源的供給，以及將這些生產(chǎn)要素轉(zhuǎn)化為產(chǎn)品與服務(wù)的可行技術(shù)。Inthelong-run,aneconomy’sproductionofgoodsandservicesdependsonitssuppliesoflabor,capital,andnaturalresourcesandontheavailabletechnologyusedtoturnthesefactorsofproductionintogoodsandservices.價(jià)格水平在長(zhǎng)期中不影響這些變量。Thepriceleveldoesnotaffectthesevariablesinthelongrun.33長(zhǎng)期總供給曲線(xiàn)

TheLong-RunAggregate-SupplyCurve...QuantityofOutputNaturalrateofoutputPriceLevel0Long-runaggregatesupplyP1P22.…不影響長(zhǎng)期中物品與服務(wù)的供給數(shù)量doesnotaffectthequantityofgoodsandservicessuppliedinthelongrun.1.價(jià)格水平的改變Achangeinthepricelevel…34長(zhǎng)期總供給曲線(xiàn)

TheLong-RunAggregateSupplyCurve長(zhǎng)期總供給曲線(xiàn)垂直于自然產(chǎn)出率處。Thelong-runaggregatesupplycurveisverticalatthenaturalrateofoutput.這一生產(chǎn)水平也被稱(chēng)為潛在產(chǎn)出或充分就業(yè)產(chǎn)出。

Thislevelofproductionisalsoreferredtoaspotentialoutputorfull-employmentoutput.35長(zhǎng)期總供給曲線(xiàn)為什么會(huì)移動(dòng)WhytheLong-RunAggregateSupplyCurveMightShift任何改變自然產(chǎn)出率的經(jīng)濟(jì)變化都會(huì)移動(dòng)長(zhǎng)期總供給曲線(xiàn)。Anychangeintheeconomythataltersthenaturalrateofoutputshiftsthelong-runaggregate-supplycurve.這樣的移動(dòng)可以按照古典模型中影響產(chǎn)出的若干因素來(lái)分類(lèi)。Theshiftsmaybecategorizedaccordingtothevariousfactorsintheclassicalmodelthataffectoutput.36長(zhǎng)期總供給曲線(xiàn)為什么移動(dòng)

WhytheLong-RunAggregateSupplyCurveMightShift來(lái)自勞動(dòng)的移動(dòng)ShiftsarisingfromLabor來(lái)自資本的移動(dòng)ShiftsarisingfromCapital來(lái)自自然資源的移動(dòng)ShiftsarisingfromNaturalResources來(lái)自技術(shù)知識(shí)的移動(dòng)ShiftsarisingfromTechnologicalKnowledge371.在長(zhǎng)期中，技術(shù)進(jìn)步移動(dòng)長(zhǎng)期總供給Inthelong-run,technologicalprogressshiftslong-runaggregatesupply...LRAS2000LRAS1990長(zhǎng)期增長(zhǎng)與通貨膨脹……Long-RunGrowthandInflation...QuantityofOutputPriceLevel0P1980Y1980AD1980P2000P1990LRAS19802.…貨幣供給的增長(zhǎng)移動(dòng)總需求andgrowthinthemoneysupplyshiftsaggregate-demand...AD2000AD19904.…和持續(xù)的通貨膨脹andongoinginflation.Y1990Y20003.…導(dǎo)致產(chǎn)出增長(zhǎng)leadingtogrowthinoutput...38長(zhǎng)期增長(zhǎng)與通貨膨脹

Long-RunGrowthandInflation短期的產(chǎn)出與價(jià)格波動(dòng)應(yīng)該被看成是對(duì)持續(xù)的長(zhǎng)期趨勢(shì)的偏離。Short-runfluctuationsinoutputandpricelevelshouldbeviewedasdeviationsfromthecontinuinglong-runtrends.39短期總供給曲線(xiàn)為什么向上傾斜

WhytheShort-RunAggregate

SupplyCurveSlopesUpwardintheShortRun在短期內(nèi)，經(jīng)濟(jì)中整體價(jià)格水平的上升傾向于增加物品與服務(wù)的供給數(shù)量。Intheshortrun,anincreaseintheoveralllevelofpricesintheeconomytendstoraisethequantityofgoodsandservicessupplied.價(jià)格水平的下降傾向于減少物品與服務(wù)的供給數(shù)量。Adecreaseinthelevelofpricestendstoreducethequantityofgoodsandservicessupplied.40短期總供給曲線(xiàn)……

TheShort-RunAggregate

SupplyCurve...QuantityofOutputPriceLevel0Short-runaggregatesupplyY1P1Y22.減少了短期內(nèi)物品與服務(wù)的供給數(shù)量reducesthequantityofgoodsandservicessuppliedintheshortrun.P21.價(jià)格水平的下降A(chǔ)decreaseinthepricelevel41短期總供給曲線(xiàn)為什么向上傾斜

WhytheShort-RunAggregate

SupplyCurveSlopesUpwardintheShortRun錯(cuò)覺(jué)理論TheMisperceptionsTheory粘性工資理論TheSticky-WageTheory粘性?xún)r(jià)格理論TheSticky-PriceTheory42錯(cuò)覺(jué)理論

TheMisperceptionsTheory總體價(jià)格水平的改變，暫時(shí)性地誤導(dǎo)供給者，讓他們?cè)诔鍪圩约寒a(chǎn)出的市場(chǎng)上，看不清正在發(fā)生什么Changesintheoverallpriceleveltemporarilymisleadsuppliersaboutwhatishappeninginthemarketsinwhichtheyselltheiroutput:更低的價(jià)格水平導(dǎo)致了對(duì)相對(duì)價(jià)格的錯(cuò)覺(jué)。Alowerpricelevelcausesmisperceptionsaboutrelativeprices.這種錯(cuò)覺(jué)使得供給者減少物品與服務(wù)的供給數(shù)量。Thesemisperceptionsinducesupplierstodecreasethequantityofgoodsandservicessupplied.43粘性工資理論

TheSticky-WageTheory名義工資的調(diào)整是緩慢的，或者說(shuō)，在短期內(nèi)是“粘性的”。Nominalwagesareslowtoadjust,orare“sticky”intheshortrun:工資并不隨著價(jià)格水平的下降而立即調(diào)整。Wagesdonotadjustimmediatelytoafallinthepricelevel.更低的價(jià)格水平使得雇傭和生產(chǎn)的利潤(rùn)更低。Alowerpricelevelmakesemploymentandproductionlessprofitable.這就導(dǎo)致企業(yè)減少物品與服務(wù)的供給數(shù)量。Thisinducesfirmstoreducethequantityofgoodsandservicessupplied.44粘性?xún)r(jià)格理論

TheSticky-PriceTheory某些物品與服務(wù)的價(jià)格為適應(yīng)經(jīng)濟(jì)狀況變化所進(jìn)行的調(diào)整是遲緩的。Pricesofsomegoodsandservicesadjustsluggishlyinresponsetochangingeconomicconditions:價(jià)格水平的未預(yù)料到的下降，留下某些企業(yè)的價(jià)格超過(guò)了合意的水平。Anunexpectedfallinthepricelevelleavessomefirmswithhigher-than-desiredprices.這會(huì)壓低銷(xiāo)售，引起企業(yè)減少物品與服務(wù)的生產(chǎn)數(shù)量Thisdepressessales,whichinducesfirmstoreducethequantityofgoodsandservicestheyproduce.45短期總供給曲線(xiàn)為什么向上傾斜

WhytheShort-RunAggregate

SupplyCurveSlopesUpwardintheShortRun所有這三個(gè)理論都表明，當(dāng)實(shí)際價(jià)格水平背離人們預(yù)期的（expected）價(jià)格水平時(shí)，產(chǎn)量就背離其自然率。用數(shù)學(xué)公式表述如下：

產(chǎn)品供給量＝自然產(chǎn)量率＋a×(實(shí)際價(jià)格水平－預(yù)期價(jià)格水平）短期中，預(yù)期價(jià)格水平難以調(diào)整，實(shí)際價(jià)格水平的上升增加了產(chǎn)品供給量，總供給曲線(xiàn)向上傾斜。長(zhǎng)期中，預(yù)期價(jià)格水平得到調(diào)整，以致與實(shí)際價(jià)格水平相等，總供給曲線(xiàn)垂直于自然產(chǎn)量率處。46短期總供給曲線(xiàn)為什么向上傾斜

WhytheShort-RunAggregate

SupplyCurveSlopesUpwardintheShortRun在短期內(nèi)，實(shí)際價(jià)格下降……而預(yù)期價(jià)格不變……結(jié)果是……錯(cuò)覺(jué)理論……供給者自己的產(chǎn)品價(jià)格下降……供給者認(rèn)為其他產(chǎn)品價(jià)格不變供給者誤認(rèn)為自己產(chǎn)品的相對(duì)價(jià)格下降，從而減少產(chǎn)出粘性工資理論……供給者自己的產(chǎn)品價(jià)格下降……供給者不能調(diào)整名義工資供給者由于產(chǎn)品價(jià)格下降而減少產(chǎn)出粘性?xún)r(jià)格理論……其他供給者的價(jià)格下降……供給者自己產(chǎn)品的價(jià)格無(wú)法調(diào)整供給者自己產(chǎn)品的相對(duì)價(jià)格上升，需求下降，從而減少產(chǎn)出。47總供給曲線(xiàn)為什么會(huì)移動(dòng)

WhytheAggregateSupplyCurveMightShift來(lái)自勞動(dòng)力的移動(dòng)ShiftsarisingfromLabor來(lái)自資本的移動(dòng)ShiftsarisingfromCapital來(lái)自自然資源的移動(dòng)ShiftsarisingfromNaturalResources.來(lái)自技術(shù)的移動(dòng)ShiftsarisingfromTechnology.來(lái)自預(yù)期價(jià)格水平的移動(dòng)ShiftsarisingfromtheExpectedPriceLevel.48預(yù)期價(jià)格水平的上升減少了物品與服務(wù)的供給數(shù)量，將短期總供給曲線(xiàn)向左移動(dòng)。Anincreaseintheexpectedpricelevelreducesthequantityofgoodsandservicessuppliedandshiftstheshort-runaggregatesupplycurvetotheleft.預(yù)期價(jià)格水平的下降增加了物品與服務(wù)的供給數(shù)量，將短期總供給曲線(xiàn)向右移動(dòng)。Adecreaseintheexpectedpricelevelraisesthequantityofgoodsandservicessuppliedandshiftstheshort-runaggregatesupplycurvetotheright.總供給曲線(xiàn)為什么會(huì)移動(dòng)

WhytheAggregateSupplyCurveMightShift49長(zhǎng)期均衡

TheLong-RunEquilibriumQuantityofOutput產(chǎn)量PriceLevel價(jià)格水平0Short-runaggregatesupply短期總供給Long-runaggregatesupply長(zhǎng)期總供給總需求AggregateDemandAEquilibrium

price均衡價(jià)格Naturalrateofoutput自然產(chǎn)出率50總需求移動(dòng)

ShiftsinAggregateDemand在短期內(nèi)，總需求的移動(dòng)導(dǎo)致經(jīng)濟(jì)中物品與服務(wù)的產(chǎn)出發(fā)生波動(dòng)。Intheshortrun,shiftsinaggregatedemandcausefluctuationsintheeconomy’soutputofgoodsandservices.在長(zhǎng)期中，總需求的移動(dòng)影響整體的價(jià)格水平但不影響產(chǎn)出。Inthelongrun,shiftsinaggregatedemandaffecttheoverallpricelevelbutdonotaffectoutput.1.總需求減少Adecreaseinaggregatedemand…AD2總需求的收縮……

AContractioninAggregateDemand...QuantityofOutputPriceLevel0Short-runaggregatesupply,AS1

Long-runaggregatesupplyAggregatedemand,AD1AP1Y1BP2Y22.…導(dǎo)致產(chǎn)出在短期內(nèi)下降causesoutputtofallintheshortrun…AS2CP33.…但是隨著時(shí)間推移，短期總供給曲線(xiàn)移動(dòng)butovertime,theshort-runaggregate-supplycurveshifts…4.…產(chǎn)出回到其自然率上andoutputreturnstoitsnaturalrate.52總供給的不利移動(dòng)

AnAdverseShiftinAggregateSupply總供給的某個(gè)決定因素的下降將曲線(xiàn)向左移動(dòng)。Adecreaseinoneofthedeterminantsofaggregatesupplyshiftsthecurvetotheleft:產(chǎn)出下降到自然率之下。Outputfallsbelowthenaturalrateofemployment.失業(yè)增加Unemploymentrises.價(jià)格上升Thepricelevelrises.531.短期總供給曲線(xiàn)的不利移動(dòng)Anadverseshiftintheshort-runaggregate-supplycurve…AS2Long-runaggregatesupplyShort-runaggregatesupply,AS1QuantityofOutputPriceLevel0AggregatedemandAY1P1總供給的不利移動(dòng)……

An

AdverseShiftinAggregateSupply...3.…和價(jià)格水平上升andthepriceleveltorise.

P22.…導(dǎo)致產(chǎn)出下降causesoutputtofall…BY254滯脹

Stagflation總供給的不利移動(dòng)導(dǎo)致滯脹——衰退和通貨膨脹并存。Adverseshiftsinaggregatesupplycausestagflation—acombinationofrecessionandinflation.產(chǎn)出下降，價(jià)格上升。Outputfallsandpricesrise.政策制訂者能夠影響總需求，但不能同時(shí)抵消這兩種不利的影響。Policymakerswhocaninfluenceaggregatedemandcannotoffsetbothoftheseadverseeffectssimultaneously.55對(duì)于衰退的政策反應(yīng)

PolicyResponsestoRecession政策制定者對(duì)衰退的反應(yīng)可以是以下方式之一Policymakersmayrespondtoarecessioninoneofthefollowingways:什么也不做，等待價(jià)格和工資的調(diào)整。Donothingandwaitforpricesandwagestoadjust.采取行動(dòng)，通過(guò)貨幣與財(cái)政政策來(lái)增加總需求。Takeactiontoincreaseaggregatedemandbyusingmonetaryandfiscalpolicy.56AS21.當(dāng)短期總供給減少Whenshort-runaggregatesupplyfalls…適應(yīng)總供給的不利移動(dòng)……

AccommodatinganAdverseShiftinAggregateSupply...QuantityofOutputNaturalrateofoutputPriceLevel0Short-runaggregatesupply,AS1

Aggregatedemand,AD1Long-runaggregatesupplyAP1P2P33.…這會(huì)引起價(jià)格上升whichcausesthepriceleveltorise4.…但是保持產(chǎn)出處于自然率butkeepsoutputatitsnaturalrate.C2.…政策制定者可以通過(guò)擴(kuò)張總需求來(lái)適應(yīng)這一移動(dòng)policymakerscanaccommodatetheshiftbyexpandingaggregatedemand…AD257總供給移動(dòng)的效應(yīng)

TheEffectsofaShiftinAggregateSupply總供給的移動(dòng)可能引起滯脹——衰退與通貨膨脹并存。Shiftsinaggregatesupplycancausestagflation–acombinationofrecessionandinflation.政策制定者能夠影響總需求，卻不能同時(shí)抵消這兩種不利的影響。Policymakerswhocaninfluenceaggregatedemandcannotoffsetbothoftheseadverseeffectssimultaneously.58總結(jié)

Summary所有社會(huì)都經(jīng)歷了圍繞長(zhǎng)期趨勢(shì)的短期經(jīng)濟(jì)波動(dòng)Allsocietiesexperienceshort-runeconomicfluctuationsaroundlong-runtrends.這些波動(dòng)是不規(guī)則的，大多不可預(yù)測(cè)。Thesefluctuationsareirregularandlargelyunpredictable.當(dāng)衰退發(fā)生時(shí)，實(shí)際GDP和其他一些衡量收入、支出和生產(chǎn)的指標(biāo)都會(huì)下降，失業(yè)上升。Whenrecessionsoccur,realGDPandothermeasuresofincome,spending,andproductionfall,