8SHORT-RUN

ECONOMICFLUCTUATIONS短期經(jīng)濟(jì)波動20Aggregate

Demand

andAggregate

Supply總需求與總供給本章我們將探索這些問題的答案：什么是經(jīng)濟(jì)波動？它們的特點是什么？總需求與總供給模型如何解釋經(jīng)濟(jì)波動？為什么總需求曲線向右下方傾斜？什么使總需求曲線移動？短期總供給曲線的斜率是多少？長期的呢？什么使總供給曲線移動？3Short-Run

EconomicFluctuationsEconomic

activity

fluctuates

from

year

toyear.In

most

years

production

of

goods

andservices

rises.On

average

over

the

past

50

years,production

in

the

U.S.

economy

has

grownby

about

3

percent

per

year.In

some

years

normal

growth

does

not

occur,causing

a

recession.短期經(jīng)濟(jì)波動經(jīng)濟(jì)活動每年都有波動。在大多數(shù)年份，物品與勞務(wù)的產(chǎn)量增加了。在過去的50年間，美國經(jīng)濟(jì)的產(chǎn)量平均每年增長3%左右。在一些年份，并沒有出現(xiàn)這種正常增長，導(dǎo)致衰退。Short-RunEconomic

Fluctuations短期經(jīng)濟(jì)波動A

recession

is

a

period

of

decliningreal

incomes,

and

risingunemployment.衰退——實際GDP下降和失業(yè)增加的時期。A

depression

is

a

severe

recession.蕭條——嚴(yán)重的衰退。20.1

THREE

KEY

FACTS

ABOUTECONOMIC

FLUCTUATIONS(1)Economic

fluctuations

are

irregular

andunpredictable.–

Fluctuations

in

the

economy

are

often

calledthe

business

cycle.(2)Most

macroeconomic

variablesfluctuate

together.(3)As

output

falls,

unemployment

rises.20.1

關(guān)于經(jīng)濟(jì)波動的三個事實(1)經(jīng)濟(jì)波動是無規(guī)律的和無法預(yù)測的。經(jīng)濟(jì)中的波動通常被稱為經(jīng)濟(jì)周期。(2)大多數(shù)宏觀經(jīng)濟(jì)變量同時波動。(3)隨著產(chǎn)量減少，失業(yè)增加。Figure

1

A

Look

AtShort-Run

EconomicFluctuationsReal

GDP(a)

Real

GDPBillions

of1996

Dollars$10,0009,0008,0007,0006,0005,0004,0003,0002,0001965

1970

1975

1980

1985

1990

1995

2000圖1.觀察短期經(jīng)濟(jì)波動Real

GDP(a)實際GDP1996的10億美元$10,0009,0008,0007,0006,0005,0004,0003,0002,0001965

1970

1975

1980

1985

1990

1995

2000Most

macroeconomic

variables

fluctuatetogether

大多數(shù)宏觀經(jīng)濟(jì)變量一起波動.Most

macroeconomic

variables

that

measuresome

type

of

income

or

production

fluctuateclosely

together

大多數(shù)衡量某種收入或產(chǎn)出的宏觀經(jīng)濟(jì)變量同時波動.Although

many

macroeconomic

variablesfluctuate

together,they

fluctuate

by

differentamounts

盡管很多宏觀經(jīng)濟(jì)變量一起波動，但是它們波動的大小并不同.Figure

1

A

Look

AtShort-Run

EconomicFluctuations(b)

Investment

SpendingBillions

of1996

Dollars$1,8001,6001,4001,2001,0008006004002001965

1970

1975

1980

1985

1990

1995

2000Investment

spending圖1.觀察短期經(jīng)濟(jì)波動(b)投資支出1,4001,2001,0008006004002001965

1970

1975

1980

1985

1990

1995

2000Investment

spending1996的10億美元$1,8001,600As

output

falls,unemployment

rises隨著產(chǎn)量減少，失業(yè)增加.Changes

in

real

GDP

are

inversely

relatedto

changes

in

the

unemploymentrate

實際

GDP的變化與失業(yè)率的變化是反向相關(guān)的.During

times

of

recession,unemploymentrises

substantially

在衰退期間，失業(yè)率大幅上升.Figure

1

A

Look

AtShort-Run

EconomicFluctuations(c)

Unemployment

Rate06428Percent

ofLabor

Force12101965

1970

1975

1980

1985

1990

1995

2000Unemployment

rateCopyright

?

2004

South-Western圖1.告步觀察親短期紡經(jīng)濟(jì)練波動(c)失業(yè)蒜率06428勞動力懲的百分比驅(qū)1210196錯5197殃0197趨5198苗0198束5199鞠0199藏5200謙0Unemploymentr立a芽te錫20.2EXPLAININGSHORT-RUNECONO速M(fèi)ICFLUCTUATIONS(1)HowtheShortRunDiffersfromtheLongRunMosteconomistsbelievethatclassicaltheorydescribestheworldinthelongrunbutnotintheshortrun.Changesinthemoneysupplyaffectnominalvariablesbutnotrealvariablesinthelongrun.Theassumptionofmonetaryneutralityisnotappropriatewhenstudyingyear-to-yearchangesintheeconomy.20.2解釋短期經(jīng)濟(jì)波動(1)長期與短期有什么不同大多數(shù)經(jīng)濟(jì)學(xué)家認(rèn)為，古典經(jīng)濟(jì)理論描述長期世界，并不描述短期世界。在長期中，貨幣供給的變化影響名義變量，而不影響實際變量。在研究逐年的經(jīng)濟(jì)變動時，貨幣中性的假設(shè)就不再適用了。TheBasicModelofEconomicFluctuations(2)Twovariablesareusedtodevelopamodeltoanalyzetheshort-runfluctuations.Theeconomy’soutputofgoodsandservicesmeasuredbyrealGDP.TheoverallpricelevelmeasuredbytheCPIortheGDPdeflator.經(jīng)濟(jì)波動的基本模型(2)兩個變量被用來建立模型分析短期經(jīng)濟(jì)波動。用實際GDP衡量的經(jīng)濟(jì)中的物品與勞務(wù)的產(chǎn)量。用CPI或GDP平減指數(shù)衡量的物價總水平。(3)TheBasicModelofEconomicFluctuations經(jīng)濟(jì)波動的基本模型TheBasicModelofAggregateDemandandAggregateSupply總需求與總供給基本模型–

Economistusethemodelofaggregatedemandandaggregatesupplytoexplainshort-runfluctuationsineconomicactivityarounditslong-runtrend.經(jīng)濟(jì)學(xué)家用總需求與總供給模型來解釋經(jīng)濟(jì)活動圍繞其長期趨勢的短期波動的模型。Theaggregate-demandcurveshowsthequantityofgoodsandservicesthathouseholds,firms,andthegovernmentwanttobuyateachpricelevel.總需求曲線——一條表示在每一種物價水平時家庭、企業(yè)和政府想要購買的物品與勞務(wù)量的曲線。Theaggregate-supplycurveshowsthequantityofgoodsandservicesthatfirmschoosetoproduceandsellateachpricelevel.總供給曲線——一條表示在每一種物價水平下企業(yè)選擇生產(chǎn)并銷售的物品與勞務(wù)量的曲線。Fi趁gur施e2獎A引牌ggr濃e炊gat擴(kuò)eD燒蘿em漠a(chǎn)nd挖虎and翅A烈gg嗎r腿ega勝te逐S常u灑ppl行y...棵Qua貓nt屠it燥yo祝f沿Out提pu開tPri寬ce煎Le遲vel氏0AggregatesupplyAggregatedemandEquilibriumoutputEquilibriumprice

level圖2.挪沒總需塌求與痕總供凝給牙…產(chǎn)量物價水平0總供給總需求均衡產(chǎn)量均衡物價水平20.3TheAggregateDemandCurve總需求曲線ThefourcomponentsofGDP(Y)contributetotheaggregatedemandforgoodsandservices.GDP(Y)的四個組成部分對物品與勞務(wù)的總需求做貢獻(xiàn)。Y=C+I+G+NXFi拳gur頸e3仗T沒覆heA研乘ggr雪e幕gat但e出-D尿em曲and菠酷Cur助ve的..過.Qua標(biāo)nt勿it頸yo悔f界Out投pu甚tPri愈ce蜓Lev豈el化0AggregatedemandPY

Y2P21.

A

decreasein

thepricelevel

.

.

.2.

.

.

.

increases

the

quantity

ofgoods

and

services

demanded.圖3.撞怕總需敏求曲草線…產(chǎn)量物價水平0總需求PY

Y2P21.物價水平下降...2.…物品與勞務(wù)量增加20.3.1WhytheAggregate-DemandCurveIsDownw側(cè)ardSloping為什么總需求曲線向右下方傾斜（1）ThePriceLevelandConsumption——TheWealthEffect物價水平與消費(fèi)——財富效應(yīng)（2）ThePriceLevelandInvestment——TheInterestRateEffect物價水平與投資——利率效應(yīng)（3）ThePriceLevelandNetExports——TheExchange-RateEffect物價水平與凈出口——匯率效應(yīng)（1）ThePriceLevelandConsumpt鄉(xiāng)豐ion:TheWealthEffect物價水平與消費(fèi):財富效應(yīng)Adecreaseinthepricelevelmakesconsumersfeelmorewealthy,whichinturnencouragesthemtospendmore.物價水平下降使消費(fèi)者感到更富裕，這又鼓勵他們更多地支出。Thisincreaseinconsumerspendingmeanslargerquantitiesofgoodsandservicesdemanded.消費(fèi)支出增加意味著物品與勞務(wù)的需求量更大了。（2）ThePriceLevelandInvestment:TheInterestRateEffect物價水平與投資:利率效應(yīng)Alowerpricelevelreducestheinterestrate,whichencouragesgreaterspendingoninvestmentgoods.較低的物價水平降低了利率，鼓勵了更多地支出用在投資物品上Thisincreaseininvestmentspendingmeansalargerquantityofgoodsandservicesdemanded.這種投資支出的增加意味著物品與勞務(wù)的需求量更大了（3）ThePriceLevelandNetExports:TheExchange-RateEffect物價水平與凈出口：匯率效應(yīng)WhenafallintheU.S.pricelevelcausesU.S.interestratestofall,therealexchangeratedepreciates,whichstimulatesU.S.netexports.當(dāng)美國物價水平下降引起美國利率下降時，實際匯率貶值，而且這種貶值刺激了美國的凈出口。Theincreaseinnetexportspendingmeansalargerquantityofgoodsandservicesdemanded.凈出口開支的增加意味著物品與勞務(wù)的需求量更大了20.3.2WhytheAggregate-DemandCurveMightShiftThedownwardslopeoftheaggregatedemandcurveshowsthatafallinthepricelevelraisestheoverallquantityofgoodsandservicesdemanded.Manyotherfactors,however,affectthequantityofgoodsandservicesdemandedatanygivenpricelevel.Whenoneoftheseotherfactorschanges,theaggregatedemandcurveshifts.20.3.2為什么總需求曲線會移動總需求曲線向右下方傾斜表明物價水平下降增加了物品與勞務(wù)的總需求量。但是，許多其他因素也影響既定物價水平時的物品與勞務(wù)的需求量。當(dāng)這些因素中的一種變動時，總需求曲線移動。Shiftsarisingfrom移動起因于Consumption消費(fèi)Investment投資GovernmentPurchases政府購買NetExports凈出口ShiftsintheAggregateDemandCurveQuantity

ofOutputPriceLevel0P1Y1D2Aggregatedemand,

D1Y2總需求曲線的移動產(chǎn)出物價水平0P1Y1D2總需求,D1Y2在下列各種情形中，總需求曲線會發(fā)生什么變動？A.一個十年期的投資稅收優(yōu)惠到期

B.美元匯率下降C.物價水平的下降增加了消費(fèi)者財富的真實價值

D.州政府對利息，紅利和資本收益征收新稅以取代銷售稅課堂練習(xí)1總需求曲線37一個十年期的投資稅收優(yōu)惠到期投資減少，總需求曲線向左移動美元匯率下降凈出口增加，總需求曲線向右移動物價水平的下降增加了消費(fèi)者財富的真實價值沿總需求曲線移動（財富效應(yīng)）州政府對利息，紅利和資本收益征收新稅以取 代銷售稅消費(fèi)增加，總需求曲線向右移動38課堂練習(xí)1參考答案20.4THEAGGREGATE-SUPPLYCURVE總供給曲線Inthelongrun,theaggregate-supplycurveisvertical.在長期中，總供給曲線是垂直的。Intheshortrun,theaggregate-supplycurveisupwardsloping.在短期中，總供給曲線是向右上方傾斜的。TheLong-RunAggregate-SupplyCurveInthelongrun,aneconomy’sproductionofgoodsandservicesdependsonitssuppliesoflabor,capital,andnaturalresourcesandontheavailabletechnologyusedtoturnthesefactorsofproductionintogoodsandservices.Thepriceleveldoesnotaffectthesevariablesinthelongrun.20.4.1WhytheLong-Runaggregate-supplycurveisvertical.長期總供給曲線在長期中，一個經(jīng)濟(jì)的物品與勞務(wù)供給取

決于它的資本、勞動和自然資源的供給，以及用來把資本與勞動變?yōu)槲锲放c勞務(wù)的生

產(chǎn)技術(shù)。在長期中，物價水平并不影響這些變量。20.4.1為什么長期總供給曲線是垂直的Fi行g(shù)ur湊e4桃T填剩heL吼柔ong齡-鑰Run饑A破gg走r綁ega棚te努-S宏u嚼ppl歐yC臣u害r稼veNat狼ur銀al破r絨at招e

Qua鹿nt沸it遇yo屈f站ofo搶u填t福put磁

Out蘆pu泛tPri充ce示Le括vel植0Long-runaggregatesupplyP21.

A

changein

thepricelevel

.

.

.2.

.

.

.does

not

affectthe

quantity

of

goodsand

servicessuppliedin

the

long

run.P圖4.嶼指長期販總供舍給曲劉線產(chǎn)量自然喘產(chǎn)量雁率物價水平0長期總供給P21.物價水平變動…2...并不影響長期中物品與勞務(wù)的供給量PTheLong-RunAggregate-SupplyCurve長期總供給曲線Thelong-runaggregate-supplycurveisverticalatthenaturalrateofoutput.長期總供給曲線是在自然產(chǎn)量率時的一條垂線。Thislevelofproductionisalsoreferredtoaspotentialoutputorfull-employmentoutput.這一產(chǎn)量水平也被稱為潛在產(chǎn)量或充分就業(yè)產(chǎn)量。20.4.2WhytheLong-RunAggregate-SupplyCur于veMightShift為什么長期總供給曲線會移動Anychangeintheeconomythataltersthenaturalrateofoutputshiftsthelong-runaggregate-supplycurve.經(jīng)濟(jì)中任何改變自然產(chǎn)量率的變動都會使長期總供給曲線移動。Theshiftsmaybecategorizedaccordingtothevariousfactorsintheclassicalmodelthataffectoutput.可以根據(jù)古典模型中影響產(chǎn)量的各種因素把這些移動進(jìn)行歸類。Shiftsarisingfrom移動起因于Labor勞動Capital資本NaturalResources自然資源TechnologicalKnowledge技術(shù)知識20.4.3ANewWaytoDepictLong-RunGrowthandInflation描述長期增長與通貨膨脹的新方法Short-runfluctuationsinoutputandpricelevelshouldbeviewedasdeviationsfromthecontinuinglong-runtrends.應(yīng)該把短期產(chǎn)量與物價水平波動作為與持續(xù)的長期趨勢的背離。Fi極gur恭e5逢L詢班ong喇-師Run處G腹r糖owt浮ha瞎遼ndI塵n山fl狹at類i鏡onQu妹ant禿it良yo畏f駱Out賺pu維tY1980AggregateDemand,

AD2000AD19900AD1980Y1990

Y2000Long-runaggregatesupply,LRAS1980

LRAS1990LRAS2000P19801.

In

the

long

run,technologicalprogress

shiftslong-run

aggregatesupply

.

.

.4.

.

.

.

andongoing

inflation.3.

.

.

.

leading

togrowthin

output

.

.

.P1990P20002.

.

.

.

and

growth

in

themoney

supply

shiftsaggregate

demand

.

.

.Pr嗓ice己Le山ve掀l圖5.心恭長絹期增掛長與郊通貨聾膨脹產(chǎn)量Y1980AD1990總需求AD20000長期總供給LRAS1980

LRAS1990LRAS2000P19801.在長期中，技術(shù)進(jìn)步使長期總供給移動….4.....及持續(xù).的通貨膨脹AD1980Y1990

Y20003.....引起產(chǎn)量增長….P1990P20002.....以及貨幣供給增長使總需求移動…物價水平20.4.4WhytheAggregate-SupplyCurveSl呆opesUpwardintheShortRun為什么短期中總供給曲線向右上方傾斜Intheshortrun,anincreaseintheoveralllevelofpricesintheeconomytendstoraisethequantityofgoodsandservicessupplied.在短期中,經(jīng)濟(jì)中物價總水平的上升傾向于增加物品與勞務(wù)的供給量。Adecreaseinthelevelofpricestendstoreducethequantityofgoodsandservicessupplied.物價總水平的下降傾向于減少物品與勞務(wù)的供給量。Fi過gur拋e6事T演訪heS備賴hor談t姨-R訊unA港雕ggr飄e母gat笑e-乖S周upp孝ly返震Cur誦v乎eQua喬nt陳it水yo科f西Out鋸pu晃tPri巷ce庫Lev天el捉0Short-runaggregatesupply1.

A

decreasein

thepricelevel

.

.

.2.

.

.

.

reduces

the

quantityof

goods

and

servicessupplied

in

the

short

run.YPY2P2圖6.就只短期績總供派給曲蛋線產(chǎn)量物價水平0短期總供給1.物價水平下降….2.

減少了短期中物品與勞務(wù)的供給量。YPY2P2WhytheAggregate-SupplyCurveSlopesUpwardintheShortRun為什么短期中總供給曲線向右上方傾斜TheMisperceptionsTheory錯覺理論TheSticky-WageTheory粘性工資理論TheSticky-PriceTheory粘性價格理論（1）TheMisperceptionsTheoryChangesintheoverallpriceleveltemporarilymisleadsuppliersaboutwhatishappeninginthemarketsinwhichtheyselltheiroutput:Alowerpricelevelcausesmisperceptionsaboutrelativeprices.Thesemisperceptionsinducesupplierstodecreasethequantityofgoodsandservicessupplied.（1）錯覺理論物價總水平的變動會暫時誤導(dǎo)供給者對他們出售其產(chǎn)品的市場發(fā)生的變動的看法:低物價水平引起對相對價格的錯覺。這些錯覺引起供給者減少物品與勞務(wù)的供給量。（2）TheSticky-WageTheoryNominalwagesareslowtoadjust,orare“sticky”intheshortrun:Wagesdonotadjustimmediatelytoafallinthepricelevel.Alowerpricelevelmakesemploymentandproductionlessprofitable.Thisinducesfirmstoreducethequantityofgoodsandservicessupplied.（2）粘性工資理論名義工資調(diào)整緩慢，或者說在短期中是“粘性的”:工資不能根據(jù)物價水平迅速調(diào)整。較低的物價水平使就業(yè)和生產(chǎn)不利。這就引起企業(yè)減少物品與勞務(wù)的供給量。（3）TheSticky-PriceTheoryPricesofsomegoodsandservicesadjustsluggishlyinresponsetochangingeconomicconditions:Anunexpectedfallinthepricelevelleavessomefirmswithhigher-than-desiredprices.Thisdepressessales,whichinducesfirmstoreducethequantityofgoodsand（3）粘性價格理論一些物品與勞務(wù)的價格對經(jīng)濟(jì)狀況變動的調(diào)整也是緩慢的:未預(yù)期到的物價水平下降使一些企業(yè)的價格高于合意水平。這就抑制了銷售，并引起企業(yè)減少它們生產(chǎn)的物品與勞務(wù)量。20.4.5WhytheShort-RunAggregate-SupplyCurveMightShift為什么短期總供給曲線會移動Shiftsarisingfrom移動起因于Labor勞動Capital資本NaturalResources.自然資源Technology.技術(shù)ExpectedPriceLevel.預(yù)期物價水平Anincreaseintheexpectedpricelevelreducesthequantityofgoodsandservicessuppliedandshiftstheshort-runaggregatesupplycurvetotheleft.預(yù)期物價水平上升減少了物品與勞務(wù)供給量，并使短期總供給曲線向左移動。Adecreaseintheexpectedpricelevelraisesthequantityofgoodsandservicessuppliedandshiftstheshort-runaggregatesupplycurvetotheright.預(yù)期物價水平下降增加了物品與勞務(wù)供給量，并使短期總供給曲線向右移動。Fi稀gur嗓e7冶T構(gòu)橡heL傾伸ong至-崇Run地E蛾qu記il單ib泄ri稈um色Natural

rateofoutputQua斃nt填it打yo藍(lán)f攤Out弊pu苗tPri臂ce盆Le烈vel噸0Short-runaggregatesupplyLong-runaggregatesupplyAggregatedemandAEquilibriumprice圖7.趣魂長期除均衡自然產(chǎn)量率產(chǎn)量物價水平0短期總供給長期總供給總需求A均衡價格20.5TWOCAUSESOFECONOMICFLUCTUATIONS（1）ShiftsinAggregateDemandIntheshortrun,shiftsinaggregatedemandcausefluctuationsintheeconomy’soutputofgoodsandservices.Inthelongrun,shiftsinaggregatedemandaffecttheoverallpricelevelbutdonotaffectoutput.20.5經(jīng)濟(jì)波動的兩個原因（1）總需求移動在短期中，總需求移動引起經(jīng)濟(jì)中物品與勞務(wù)產(chǎn)量的波動。在長期中，總需求移動影響物價總水平，但不影響產(chǎn)量。Fi乞gur炭e8而A仰C開拍ont毛r遮act潤i籃oni疾n牌A烘gg亦r晃ega躁te磚慘De惕ma蘿ndQua珠nt玻it旺yo烘f避Out內(nèi)pu牧tPri廳ce貴Lev腹el斜0Long-runaggregate敏supplyPYAggregatedemand,

ADAD21.

A

decrease

inaggregate

demand

.

.

.2.

.

.

.causes

output

to

fall

in

the

short

run

.

.

.Short-run

aggregatesupply,

ASAS23.

.

.

.but

overtime,

the

short-runA

aggregate-supplycurve

shifts

.

.

.4.

.

.

.

and

outputreturnsto

its

naturalrate.CP3BP2Y2圖8.趣馳總需巖求減械少產(chǎn)量物價水平0長期總供給APY總需求,ADAD21.總需求減少…..2....引起短期中產(chǎn)量減少...短期總供給,AS1AS23……但隨著時間推移，短期總供給曲線移動……4……產(chǎn)量恢復(fù)到其自然產(chǎn)量率水平。CP3BP2Y2畫出美國經(jīng)濟(jì)的AD-SRAS-LRAS圖形，從經(jīng)濟(jì)的長期均衡開始加拿大出現(xiàn)經(jīng)濟(jì)繁榮，用你的圖形分析這對美國GDP，物價水平和失業(yè)率的短期與長期影響課堂練習(xí)2模型的應(yīng)用68課堂練習(xí)2參考答案69LRASYNPYAD2SRAS2AD1SRAS14.隨時間的推移，PE上P1升，SRAS曲線一直

向左移動，直到達(dá)到

長期均衡點C。Y與失業(yè)率回到起始水平P3P2CY2BA事件：加拿大經(jīng)濟(jì)繁榮影響NX，AD曲線AD曲線向右移動短期均衡在點B。P與Y增加，失業(yè)率降低（2）AnAdverseShiftinAggregateSupplyAdecreaseinoneofthedeterminantsofaggregatesupplyshiftsthecurvetotheleft:Outputfallsbelowthenaturalrateofemployment.Unemploymentrises.Thepricelevelrises.（2）總供給的不利移動總供給決定因素中任何一種降低都使總供給曲線向左移動:產(chǎn)量下降到自然就業(yè)率水平以下。失業(yè)率上升。物價水平上漲。Fi墾gur坦e1停0翻A霧nAd形ver青se斤S生hi松ft中i辱nA凈底ggr創(chuàng)e擾gat蚊eS煙棋upp殼ly句Qua燙nt惹it薪y(tǒng)o觀f碎Out者pu楊tPri米ce惰Lev拖el薦Aggregate

demand3.

.

.

.

andthe

pricelevel

to

rise.2.

.

.

.

causes

output

to

fall

.

.

.1.

An

adverse

shift

in

the

short-runaggregate-supplycurve...Short-runaggregatesupply,

ASLong-runaggregatesupplyYAPAS2B0

Y2P2圖10麗.抗總藝供給吊的不倚利移拾動產(chǎn)量物價水平總需求2....引起產(chǎn)量減少...1.短期總供給曲線的不利移動……短期總供給AS長期總供給APAS2B3....以及物價水平上升。0

Y2

YP2TheEffectsofaShiftinAggregateSupply（1）StagflationAdverseshiftsinaggregatesupplycausestagflation—aperiodofrecessionandinflation.Outputfallsandpricesrise.Policymakerswhocaninfluenceaggregatedemandcannotoffsetbothoftheseadverseeffectssimultaneously.總供給移動的影響（1）滯脹總供給的不利移動會引起滯脹—衰退和通貨膨脹并存的時期。產(chǎn)量減少而物價上升。那些能影響總需求的決策者不能同時抵消這兩種不利的影響。（2）PolicyResponsestoRecessionPolicymakersmayrespondtoarecessioninoneofthefollowingways:Donothingandwaitforpricesandwagestoadjust.Takeactiontoincreaseaggregatedemandbyusingmonetaryandfiscalpolicy.總供給移動的影響（2）對付衰退的政策政策制定者可以用下列手段之一來對付衰退:什么也不做，等待價格和工資調(diào)整。利用貨幣和財政政策增加總需求。Fi吸gur民e1覽1勵A(yù)籠c模co略mm宏oda買ti顫ng侄鼻anA岸待dve呀r晚seS只h菊if背ti丹n棕完

Agg銅r忘ega尚te折S膨u畢ppl朵yQua敬nt纏it導(dǎo)yo撇f歷Out翻pu球tNat底u(yù)r密al濟(jì)r孩at猜eofo喂u竟t偶put雁Pri釣ce艘Lev僻el按0Short-runaggregatesupply,

ASLong-runaggregatesupplyAAS23.

.

.

.

whichcauses

theprice

levelto

risefurther

.

.

.4.

.

.

.

but

keeps

outputat

its

naturalrate.2.

.

.

.

policymakers

canaccommodate

the

shiftby

expanding

aggregatedemand

.

.

.1.

When

short-run

aggregatesupply

falls

.

.

.AD2Aggregatedemand,

ADCP3P2P圖11傭.倚抵觸消總遣供給虛的不片利移異動產(chǎn)量自然產(chǎn)鄭量率宮物價水平0短期總供給AS長期總供給ADAAS23....這引起物價水平進(jìn)一步上升……4....但產(chǎn)