1、1本科毕业论文外文翻译外文文献译文标题界定技术溢出和产品市场竞争资料来源美国国家经济研究局工作论文第13060号，2004年4月作者尼古拉斯布鲁姆，马克夏克曼，约翰范瑞内在过去三十多年里，知识溢出效应已经成了经济领域一项主要的研究课题。理论研究已经对RFIRMS0ANDMCOMPETEONLYINTHEPRODUCTMARKETALTHOUGHTHISISAHIGHLYSTYLIZEDMODELITMAKESOURKEYCOMPARATIVESTATICPREDICTIONSVERYCLEARAPPENDIXACONTAINSSEVERALEXTENSIONSTOTHEBASICMODELFI
2、RSTLY,WEALLOWOTHERFIRMSTOOVERLAPSIMULTANEOUSLYINPRODUCTMARKETANDTECHNOLOGYSPACEANDALSOALLOWFORMORETHANTHREEFIRMSINTHEECONOMYSECONDLY,WECONSIDERATOURNAMENTMODELOFRDRATHERTHANTHENONTOURNAMENTMODELWHICHISTHEFOCUSOFTHISSECTIONTHIRDLY,WEALLOWPATENTINGTOBEENDOGENOUSLYCHOSENBYFIRMSRATHERTHANONLYANINDICATOR
3、OFKNOWLEDGE,KTHECOMPARATIVESTATICRESULTSARESHOWNTOBEROBUSTTOALLTHESEEXTENSIONS1WITHONEEXCEPTIONTHATWEWILLDISCUSSBELOWSINCEWEAREATTEMPTINGTOIDENTIFYA“SOCIALEFFECT”WEMUSTADDRESSTHEMANSKI1991IDENTIFICATIONISSUESTHEPAPERHASNOMAGICBULLET,BUTDOESHAVESEVERALADVANTAGESOVEROTHERCONTRIBUTIONSINTHESPILLOVERLIT
4、ERATUREWEDONOTATTEMPTTONONPARAMETRICALLYIDENTIFYTHESPILLOVEREFFECTSWHICHMANSKISHOWSISNOTPOSSIBLEANDINSTEADMAKESOMEPARAMETRICASSUMPTIONSOVERTHEFORMOFDISTANCEMETRICFUNDAMENTALLY,IDENTIFICATIONOFTHEVARIOUSSPILLOVEREFFECTSFORFIRMICOMESFROMTWOELEMENTSATIMEINVARIANT“DISTANCE”BETWEENFIRMIANDALLOTHERFIRMSAN
5、DTHETIMEVARYINGRDOFOTHERFIRMSFOREXAMPLE,THEFACTTHATWEMEASURETWOFIRMSASCLOSEINTECHNOLOGYSPACEINDICATESTHATTHEYMAYBEBENEFITINGFROMMUTUALINTERFIRMSPILLOVERSBUTTHISISNOTNECESSARILYTHECASE,THEFIRMSWILLALSOAPPEARCLOSEINTECHNOLOGYSPACEIFTHEYHAVESOMECOMPARATIVEADVANTAGEINUTILIZINGSIMILARTECHNOLOGIESBUTTHERE
6、ISNOACTUALTECHNOLOGYSPILLOVERBETWEENTHEMINSTEAD,OURAPPLICATIONUTILIZESTHEFACTTHATTHEREAREEXOGENOUSSHOCKSDIFFERENTIALLYAFFECTINGTHERDOFOTHERFIRMSINTHEECONOMYTHESESHOCKSCANARISEFORAVARIETYOFREASONSSUCHASTHEUSRDTAXCREDITTHATCREATEDVERYHETEROGENEOUSINCENTIVESACROSSDIFFERENTCOMPANIESANOTHEREXAMPLEWOULDBE
7、THEENDOFTHECOLDWARWHICHLEDTOLARGEFALLSINTHEDEGREEOFGOVERNMENTSUPPORTFORDEFENCERELATEDRDWEIDENTIFYSPILLOVERSFROMTHEASSUMPTIONTHATAGIVENINCREASEINTHERDOFFIRMJSHOULDHAVEALARGEREFFECTONFIRMIIFITIS“CLOSE”ANDASMALLEREFFECTONFIRMIIFITIS“DISTANT”THUS,WECANCONTROLFORDISTANCEINANONPARAMETRICWAYTHROUGHFIRMFIXE
8、DEFFECTSANDFORGENERALCHANGESINRDTIMEDUMMIESANDSEEKTOIDENTIFYFROMTHEINTERACTIONOFCOURSE,THISDOESNOTREMOVEALLIDENTIFICATIONISSUESFOREXAMPLE,CONSIDERTHEPROBLEMOFATRANSITORYUNOBSERVEDSHOCKSPECIFICTOAPAIROFFIRMSCLOSEINTECHNOLOGYSPACETHISCOULDSIMULTANEOUSLYRAISETHEIRRD,PATENTS,PRODUCTIVITYANDMARKETVALUEOU
9、RAPPROACHTRIESTOMITIGATETHISPROBLEMINSEVERALWAYSFIRST,WEINCLUDEMANYCONTROLSFORTHISPOSSIBLESHOCKTIMEDUMMIES,INDUSTRYSALES,FIRMFIXEDEFFECTSANDTIMEVARYINGOTHERFIRMLEVELCOVARIATESINSOMEREGRESSIONSEGSALES,CAPITAL,LABOR,OWNRD,ETCSECOND,WEALSOLAGALLTHEFIRMLEVELVARIABLESTOAVOIDCONTEMPORANEOUSFEEDBACKMOSTIMP
10、ORTANTLY,THEMODELPREDICTSDIFFERENTIALRESPONSESACROSSDIFFERENTSPILLOVERVARIABLESINDIFFERENTEQUATIONSCONSIDERTHEMARKETVALUEEQUATION,FOREXAMPLEWEPREDICTTHATRDBYFIRMSCLOSEINTHEPRODUCTMARKETSPILLSICSHOULDHAVEANEGATIVEEFFECTONMARKETVALUEWHEREASRDBYFIRMSWHEREASFIRMSCLOSEINTECHNOLOGYSPACESPILLTECHSHOULDHAVE
11、APOSITIVEEFFECTONMARKETVALUESOANYSHOCKTHATISRAISINGOTHERFIRMSRDGENERALLYISPREDICTEDTOHAVEADIFFERENTIALEFFECTONAFIRMDEPENDINGON1ITSCLOSENESSINTHEPRODUCTSPACEVSTECHNOLOGYSPACEFURTHERMORE,INTHERDEQUATIONSPILLSICISPREDICTEDTOHAVEAPOSITIVEEFFECTONRDIFTHEREISSTRATEGICCOMPLEMENTARITYWHICHISWHATWEFINDITISHARDTOCOMEUPWITHASTORYFORWHYANOMITTEDSHOCKSHOULDINCREASEFIRMSRDBUTDEPRESSFIRMSMARKETVALUESOALTHOUGHWECANNEVERRULEOUTTHEPOSSIBILITYTHATSOMECOMPLEXINTERACTIONOFOMITTEDSHOCKSDRIVESOURRESULTSINAWORLDWITHOUTSPILLOVERS,ITSEEMSUNLIKELY
