宏观820.docx

宏观820.docx

《宏观820.docx》由会员分享，可在线阅读，更多相关《宏观820.docx（22页珍藏版）》请在冰豆网上搜索。

宏观820

第八章

1.theaggregatesupplyrelation：

Accordingtothisequation:

1）Anincreaseintheexpectedinflation,e,leadstoanincreaseininflation,.

2）Givenexpectedinflatione,anincreaseinthemarkup,,oranincreaseinthefactorsthataffectwagedetermination,z,leadtoanincreaseininflation.

3）Givenexpectedinflation,e,anincreaseintheunemploymentrate,u,leadstoadecreaseininflation,.

2.Ifwesetet=0（when

）,then:

ThisisthenegativerelationbetweenunemploymentandinflationthatPhillipsfoundfortheUnitedKingdom,andSolowandSamuelsonfoundfortheUnitedStates（ortheoriginalPhillipscurve,itmeansthatwagesettersexpectthatthepricelevelinnextyearisequaltothatincurrentyear,i.e.,inflationwillbeequaltozero）.

3.theearlyincarnation

Thewage-pricespiral:

GivenPet=Pt-1:

▪Lowunemploymentleadstoahigherwage.

▪Inresponsetothehigherwage,firmsincreasetheirprices.

▪Inresponse,workersaskforahigherwage.

▪Higherwageleadsfirmstofurtherincreaseprices.

▪Thisfurtherincreaseswagesaskedforbyworkers.

▪Theracecontinuesoverwagesandpriceinflation.

4.Mutations

1）Intheequationabove,whenequalszero,therelationbetweentheinflationrateandtheunemploymentrateis:

2）Whenispositive,theinflationratedependsonboththeunemploymentrateandlastyear’sinflationrate:

3）Whenispositive,theinflationratedependsonboththeunemploymentrateandlastyear’sinflationrate:

5.TheoriginalPhillipscurveis:

ThemodifiedPhillipscurve,alsocalledtheexpectations-augmentedPhillipscurve,ortheaccelerationistPhillipscurve,is:

第九章

1.Output,Unemployment,andInflation

Thischaptercharacterizestheeconomybythreerelations:

ØOkun’sLaw,whichrelatesthechangeinunemploymenttooutputgrowth.

ØThePhillipscurve,whichrelatesthechangesininflationtounemployment.

ØTheaggregatedemandrelation,whichrelatesoutputgrowthtobothnominalmoneygrowthandinflation.

2.Okun’slaw

Accordingtotheequationabove,thechangeintheunemploymentrateshouldbeequaltothenegativeofthegrowthrateofoutput.

Forexample,ifoutputgrowthis4%,thentheunemploymentrateshoulddeclineby4%.

Note:

Thisequationisderivedfromfollowingtwoconvenientbutrestrictiveassumption:

ØOutputmovedoneforonewithemployment,ie.Y=N;

ØLaborforcewasconstant,sochangesinemploymentwasreflectedoneforoneinoppositechangesinunemployment.

TheactualrelationbetweenoutputgrowthandthechangeintheunemploymentrateisknownasOkun’slaw.

Usingthirtyyearsofdataintheunitedstates,therelationthatbestfitsthedataisgivenby:

3.Theeffectsofmoneygrowth

ØOkun’slawrelatesthechangeintheunemploymentratetothedeviationofoutputgrowthfromnormal:

ØThePhillipscurverelatesthechangeininflationtothedeviationoftheunemploymentratefromthenaturalrate:

ØTheaggregatedemandrelationrelatesoutputgrowthtothedifferencebetweennominalmoneygrowthandinflation.

4.Themediumrun

ØInthemediumrun,theunemploymentratemustbeconstant,

ØThenaccordingOkun’slaw,theoutputmustgrowatitsnormalrateofgrowth

ØInthemediumrun,accordingtheaggregatedemandrelation,theinflationmustbeequaltonominalmoneygrowthminusnormaloutputgrowth.

Ifwedefineadjustednominalmoneygrowthasequaltonominalmoneygrowthminusnormaloutputgrowth,sointhemediumrun,inflationequalsadjustednominalmoneygrowth.

Ifinflationisconstant---equalsadjustednominalmoneygrowth,accordingtothephillipscurve,theunemploymentratemustequaltothenaturalrateofunemployment.

Let’ssummarize:

Inthemediumrun,outputisequaltothenormalgrowthrate;unemploymentisequaltothenaturalrate,bothofthemareindependentofnominalmoneygrowth.

Sonominalmoneygrowthaffectsonlyinflation-----changesinthelevelofnominalmoneyareneutralinthemediumrun,whicharereflectedoneforoneinchangesintherateofinflation..

“Inflationisalwaysandeverywhereamonetaryphenomenon.”_Miltonfriedman

5.Thefirstpass

InthePhillipscurverelationabove,disinflation—adecreaseininflationrate—canbeobtainedonlyatthecostofhigherunemployment.（note:

deflation—decreaseinthepricelevel,equivalentnegativeinflation）

第十章

1.Thefactsofgrowth

Growthisthesteadyincreaseinaggregateoutputovertime.

2.Thegrowthinrichcountries

OutputpercapitaequalsGDPdividedbypopulation.

Thestandardoflivingdependsontheevolutionofoutputpercapita,nottotaloutput.

3.ThedecreaseingrowthratessincetheMid-1970

Averyusefulruleisthe“ruleof70.”Ifavariablegrowsatx%ayear,thenitwilltakeapproximately70/xyearsforthevariabletodouble.

4.Theaggregateproductionfunction

Theaggregateproductionfunctionisaspecificationoftherelationbetweenaggregateoutputandtheinputsinproduction.

Y=aggregateoutput.

K=capital—thesumofallthemachines,plants,andofficebuildingsintheeconomy.

N=labor—thenumberofworkersintheeconomy.

ThefunctionF,tellsushowmuchoutputisproducedforgivenquantitiesofcapitalandlabor.

5.Thesourcesofgrowth

Usingtheaboveequation,wecannowdeterminewheregrowthcomesfrom:

A）Increasesinoutputperworker（Y/N）cancomefromincreasesincapitalperworker（K/N）.

B）Ortheycancomefromimprovementsinthestateoftechnologythatshifttheproductionfunction,F,andleadtomoreoutputperworkergivencapitalperworker.

Growthcomesfromcapitalaccumulationandfromtechnologicalprogress.

Wecanthinkofgrowthascomingfromcapitalaccumulationandfromtechnologicalprogress,butthesetwofactorsplayverydifferentrolesinthegrowthprocess:

a）Capitalaccumulationbyitselfcannotsustaingrowth.

b）Sustainedgrowthrequiressustainedtechnologicalprogress.Therateofgrowthofoutputpercapitaiseventuallydeterminedbytheeconomy’srateoftechnologicalprogress.

第十一章

1.Interactionsbetweenoutputandcapital

Atthecenterofthedeterminationofoutputinthelongrunaretworelationsbetweenoutputandcapital:

a）Theamountofcapitaldeterminestheamountofoutputbeingproduced.

b）Theamountofoutputdeterminestheamountofsavingandinvestment,andsotheamountofcapitalbeingaccumulated.

2.Outputandinvestment

Wemakethreeassumptionstoderivetherelationbetweenoutputandinvestment:

1）Weassumetheeconomyisclosed.

2）Weassumepublicsaving,T–G,isequaltozero.

3）Weassumethatprivatesavingisproportionaltoincome,so

Combiningthesetworelationsgives:

3.Investmentandaccumulation

Theevolutionofthecapitalstockisgivenby:

denotestherateofdepreciation.

Combiningtherelationfromoutputtoinvestment,,andtherelationfrominvestmenttocapitalaccumulation,weobtainthesecondimportantrelationwewanttoexpress,fromoutputtocapitalaccumulation:

OutputandCapitalperWorker:

Rearrangingtermsintheequationabove,wecanarticulatethechangeincapitalperworkerovertime:

Inwords:

thechangeinthecapitalstockperworker（leftside）isequaltosavingperworkerminusdepreciation（rightside）.

4.Dynamicsofcapitalandoutput

Fromourmainrelationsabove,weexpressoutputperworker（Y/N）intermsofcapitalperworkertoderivetheequationbelow:

Thisrelationdescribeswhathappenstocapitalperworker.Fromthisrelationweknow:

a）Ifinvestmentperworkerexceedsdepreciationperworker,thechangeincapitalperworkerispositive:

Capitalperworkerincreases.

b）Ifinvestmentperworkerislessthandepreciationperworker,thechangeincapitalperworkerisnegative:

Capitalperworkerdecreases.

c）Thisrelationcontainsalltheinformationweneedtounderstandthedynamicofcapitalandoutputovertime.

5.Steady-statecapitalandoutput

Thestateinwhichoutputperworkerandcapitalperworkerarenolongerchangingiscalledthesteadystateoftheeconomy.Insteadystate,theleftsideoftheequationaboveequalszero,then:

Giventhesteadystateofcapitalperworker（K*/N）,thesteady-statevalueofoutputperworker（Y*/N）,isgivenbytheproductionfunction:

6.Thesavingrateandoutput

Threeobservationsabouttheeffectsofthesavingrateonthegrowthrateofoutputperworkerare:

1）Thesavingratehasnoeffectonthelongrungrowthrateofoutputperworker,whichisequaltozero.

2）Nonetheless,thesavingratedeterminesthelevelofoutputperworkerinthelongrun.Otherthingsequal,countrieswithahighersavingratewillachievehigheroutputperworkerinthelongrun.

3）Anincreaseinthesavingratewillleadtohighergrowthofoutputperworkerforsometime,butnotforever.Thatis,thesavingratedoesnotaffectthelong-rungrowthrateofoutputperworker.Afterahighersavingrate,growthwillendoncetheeconomyreachesitsnewsteadystate.

第十二章、十三章为理解内容

第十八章

1.Opennessingoodsandfinancialmarkets

Opennesshasthreedistinctdimensions:

1）Opennessingoodsmarkets,whichallowspeopletochoosebetweendomesticgoodsandforeigngoods.Animportantdeterminantoftheirdecisionsistherealexchangerate---therelativepriceofdomesticgoodsintermsofforeigngoods.whatweareconcernedaboutisFreetraderestrictionsincludetariffsandquotas.

2）Opennessinfinancialmarkets,wichallowspeopletochoosebetweendomesticassetsandforeignassets.Thisimposesatightrelationbetweentheexchangerate,bothcurrent