巴德学院利维经济研究所-聚合生产函数与索洛的“三件牛仔”（英）-2024.3.docx

aaI向Eo1.evyEconomics0InstituteofBardCollegeWorkingPaperNo.1045TheAggregateProductionFunctionandSolovv,suThreeDenials”byJesusFelipe(*)SchoolofEconomics,De1.aSalleUniversity(Manila,Philippines)andJohnMcCombie(*)UniversityofCambridge,Cambridge,UKMarch2024Authorcontactinformation:Felipe(iesus.felir)e(>dlsu.edu.uh):McCombie(jslm2(5)cam.ac.uk)The1.evyEconomicsInstituteWorkingPaperCollectionpresentsresearchinprogressby1.evyInstitutescholarsandconferenceparticipants.Thepurposeoftheseriesistodisseminateideastoandelicitcommentsfromacademicsandprofessionals.1.evyEconomicsInstituteofBardCollege,foundedin1986,isanonprofit,nonpartisan,independentlyfundedresearchorganizationdevotedtopublicservice.Throughscholarshipandeconomicresearch,itgeneratesviable,effectivepublicpolicyresponsestoimportanteconomicPrObIemSIhatPrOfbUndIyaffeciIhequalilyOfIifeinIheUnitedSlaIeSandabroad.1.evyEconomicsInstituteP.O.Box5000Annandale-on-Hudson,NY12504-5000Copyright©1.evyEconomicsInstitute2024AllrightsreservedISSN1547-366XABSTRACTThispaperoffersaretrospectiveviewofthekeypillarofSolow,sneoclassicalgrowthmodel,namelytheaggregateproductionfunction.Wereviewhowthistoolcametolifeandhowithassurviveduntiltoday,despitethreecriticismsthatundermineditsraisond,etre.TheyaretheCambridgeCapitalTheoryControversies,theAggregationProblem,andtheAccountingIdentity.Thesecriticismswereforgottenbytheprofession,notbecausetheywerewrongbutbecauseofthekeyroleplayedbyRobertSolowinthefield.Today,thesecriticismsarenotevenmentionedwhenstudentsareintroducedto(neoclassical)growththeory,whichispresentedinmosteconomicsdepartmentsandmacroeconomicstextbooksastheonlytheoryworthstudying.JE1.C1.ASSIFICATION:B22,B31,B32,B41,E13,E25KEYWORDS:AccountingIdentity,AggregationProblem,CambridgeCapitalTheoryControversies,SolowINTRODUCTIONRobertSolow,oneofthemostnotableeconomistsofthetwentiethcenturydiedDecember21,2023,attheageof99.Hewascertainlyagreatresearcher,someoneinterestedinsociety,srealproblems,andthosewhostudiedatMITduringhistenureconsiderhewasagreatinstructor.SolowarrivedatMITin1949asaprofessorofstatistics.TogetherwithPaulSamuelson,hebuiltoneofthebestregardedeconomicsdepartmentsintheworld.Botheconomistswereinstrumentalinlayingthefoundationsoftheneoclassicalsynthesis.WhilethistooksomeelementsofKeynes,GeneralTheory,itwas,insomerespects,areturntothepre-Keynesianworld.Theneoclassicalsynthesishadthreepillars:microeconomiccompetitivegeneralequilibriumtheory,thePhillipscurve,andSolow,s(1956)growthmodel.ThesynthesisassertedtheefficacyofKeynesianpolicyintheshortrun,butassertedabeliefincompetitivemarketforcesandSay,s1.awinthelongrun(inparticularinthecaseofSolow,sgrowthmodel).Asaneconomistinterestedinsociety,srealproblems,Solowwasconcerned,interalia,withthecausesofunemployment(Solow1980),andviewedthelabormarketasasocialinstitutionandnotlikethetypicalmarketforagood(Solow1990).Hetookpartinthetwomostimportantintellectualdebatesineconomicsofthetwentiethcentury:theCambridgeCapitalTheoryControversies(CCTCs)(mainlywithJoanRobinsonintheUK)andwiththenewclassicalmacroeconomists(mainlywithMiltonFriedmaninChicago).SolowwasawardedtheNobelPrizein1987forhiscontributionstothetheoryofeconomicgrowth.Solow,s(1956)growthmodelincorporatedanaggregateproductionfunction(APF).Thisconceptbecameapillarofneoclassicalmacroeconomicsandcertainlyofsubsequentneoclassicalgrowthmodels.Productionfunctionsappearedineconomicsinthenineteenthcentury.Itwasnot,however,untilCobbandDouglas(1928)thatonewasestimatedfortheAmericaneconomyusingstatisticalmethods,whichrequiredusingaggregatedata(indices)foroutput,labor,andcapital.Inthisarticle,theyfoundtheelasticitiesofoutputwithrespecttolaborandcapitaltobe0.75and0.25,respectively,closetothefactorshares.Theirworkwasinitiallyreceivedwithgreathostility,tothepointthatDouglasconsideredgivingup.Hemovedfromtheoriginalworkwithtimeseriestocross-sectionaldata,whichproducedmuchbetterstatisticalresults(McCombie1998;FelipeandMcCombie2013,chapter4).AggregateproductionfunctionscontinuedbeingusedduringthefollowingdecadesbutitwasnotuntilSolow,s(1956,1957)twoseminalpapersthattheybecameastandardconceptinmacroeconomics.Thiswasdespitesomedoubtsabouttheirtheoreticalandempiricalfoundations,asweshallseebelow.Solow,s(1956)growthmodelisstillusedtodaytointroducestudentstogrowththeory.InSolow(1957),theAPFservedasthetooltoempiricallyapportionthecontributionsoftechnicalprogress(totalfactorproductivitygrowthorSolowresidual)andthoseofcapitalandlaborgrowth,tooutputgrowth,intheUSeconomybetween1909and1949.Althoughtotalfactorproductivityhadbeencalculatedbefore,thiswasthefirsttimeithadbeenexplicitlylinkedtoproductiontheory.The1957paperlaunchedtheneoclassicalresearchprogramongrowth,inparticulargrowthaccountingexercisesandtheestimationoftotalfactorproductivitygrowth.ThepresentpaperoffersaretrospectiveviewoftheAPF,inparticularofthreefundamentalcriticismsitwassubjectedto,andofhow,despitethesecriticisms,ithassurvivedthetestoftime.ThesecritiquesaretheCambridgeCa