《CitiesandDevelopment》Author:J.VernonHendersonPublishedsource:JRegSci.2010February;50(1):515–540.Department:DepartmentofEconomics,BrownUniversity,andNationalBureauofEconomicResearch[&]JVernonHenderson.CitiesandDevelopment[J].JournalofRegionalScience,2010,50(1):515-540Speaker:CaiYong-longSouthChinaNormalUniversityintroductionUrbanizationandeconomicdevelopmentarecloselyintertwined.Whileurbanizationpersedoesnotcausedevelopment,sustainedeconomicdevelopmentdoesnotoccurwithouturbanization.fullurbanization—movingacountryfromasituationwhere10–20%ofthepopulationisurbanizedtoonewhere60–85%isurbanized--occursnowofteninaspanofabout30years,asopposedtothemoreleisurelypaceofurbanizationintoday‘sdevelopedcountrieswhichplayedoutover100–150years.introductionTherearemajorissuesintoday‘surbanizationprocessconcerningtheroleofpolicyforwhichthereseemfewhistoricalcounterparts,aswewillsee.Itisthereforenecessarytodiscusstherelevantissuesofthelinksbetweenurbanizationanddevelopment.Inthinkingabouthistoricalexperienceoftoday'sdevelopedcountriesversusthecurrentexperienceindevelopingcountries,afeaturethatdistinguishesthetwoistherolethatnationalgovernmentpolicyplays.Rapidurbanizationistraumatic.Thispaperstartswitha“primer”onwhatweknowabouttheconceptualandempiricallinksbetweendevelopmentandurbanization.EmpiricalevidenceispartlybasedonhistoricalexperienceindevelopedcountriessuchastheUSA,butItrytodrawalsofromtheexperienceinsomecountriesinLatinAmericaandEastAsia,whichhavegonethroughtheurbanizationprocessandproceededtowardsmiddleincomestatusascountries.PartoneintroductionThisiscriticalquestion,facingChinaandIndiatoday,withfairlyradicalproposalsonthetablewhichwewilldiscussforextraordinarilyconcentrateddevelopment,withhugeportionsofthepopulationtopotentiallybehousedjustinmega-cities.thespecificproblem:Whateveranoptimalpatternmightbe,howcostlyaredeviations,evensignificantonesfromthatoptimalpattern?Howdoweconceptualizeandmeasureboththebenefitsandcostsofincreasedurbanconcentration;andhowaretheylinkedtoacountry'sevolvingnationalindustrialcomposition?Withinlargeclusters,ormega-cities,whatarethebestformsofspatialdevelopmentandtypesandspatialformsofinfrastructureinvestments?Firstconcernsthespatialformofdevelopment.Howspatiallyconcentratedshouldurbanizationbe—howmuchdevelopmentshouldbefocusedinmega-cities,orhugeurbanclusters,asopposedtospatiallydispersed.ParttwointroductionSecond,whatarethedeterminantsofspatialincomeinequalityandwhatistheevolutionofsuchinequalityundermassiverural-urbanmigration?Kuznets-Williamson(Williamson,1965)Doesthisfavoritismininvestmentpoliciesaffectincomeinequalitywithinandacrossregionsanditsevolution?Apotentialmechanismforincreasedincomeinequalitywithnationalregionalfavoritismislocalgovernmentpoliciesinfavoredareasthattrytorestraindirectlyorindirectlyin-migration.Thismechanismpresentsarelatedsetofissuestoanalyze.ParttwointroductionAnendnotePartthreeintroduction111111Partone:whatweknowabouturbanizationanddevelopmentTheurbanization-growthlinkAgglomerationanddevelopmentTheUrbanHierarchyChangingIndustrialCompositionwithDevelopmentChurningandStableSizeDistributionsSummaryofsomefactshigherlevelsofurbanizationasmeasuredbythepercentofthenationalpopulationthatlivesinurbanareas,isassociatedwithincreasedincomepercapita.Data:urbanizedin2004Firstarethe`static'modelsinHarris-Todaroro(1970)andtheneweconomicgeography(Krugman,1991,Fujita,Krugman,andVenables,1999)Secondaregrowthmodels,withanurbanversioninHendersonandWang(2005),1.1Theurbanization-growthlink1.1Theurbanization-growthlinkgrowthmodelslaborisreleasedfromagriculturetoworkinmanufacturingandservicesectors.Thatreleaseoccursfortworeasons.Oneisademandshifttowardsmanufacturingspurredbytechnologicalimprovementsinmanufacturingandworlddemandpatternswhereinvestorsarealwayslookingfornewlowcostcountriestohousestandardized,laborintensiveproductionofpartsandcomponents.Theotherislaborsavingimprovementsintechnologyinagriculture.Second,manufacturingandservicesenjoyeconomiesofagglomerationdiscussedbelow,whichrequiresefficientproductiontobeinhighdensitylocations,orcities.1.1Theurbanization-growthlinkWhilethereisthisassociationbetweenurbanizationanddevelopment,itisanequilibriumnotcausalrelationship.suchasinsub-Saharancountriesfrom1970–2000whereurbanizationoccursinthefaceoflittleornopercapitaincomegrowth.TheWDR,2000,notesthaturbanizationwithoutgrowthinsomeAfricancountiesinthistimeperiodmayinparthavebeenfueledbyapushoutofruralareasduetowarandlackofupkeepofruralinfrastructure.Correspondingly,econometricstudiesindicatethat,whiletheformofurbanizationcausallyaffectsgrowth,urbanizationpersedoesnot.1.2Agglomerationanddevelopment•Therearetwointer-relatedconceptualissuesastowhydevelopmentislinkedtoindustrialagglomerationincities.localizedexternaleconomiesofscale,Withtheexceptionofhightechindustries,thereislimitedevidencethatthesemanufacturingindustriesbenefitfromgreatercitysizeperse;rathertheybenefitfrombeingingreaterclustersoflike,orinter-relatedactivities(localizedinformationspillovers).Theseareapow