中国和美国在合作中生产更具影响力的人工智能研究

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arXiv:2304.11123v1[cs.CY]21Apr2023

ChinaandtheU.S.producemoreimpactfulAIresearchwhencollaboratingtogether

BedoorAlShebli1*,ShahanAliMemon,JamesA1.Evans2,andTalalRahwan3*

1SocialScienceDivision,NewYorkUniversityAbuDhabi,UAE.

2DepartmentofSociology,UniversityofChicago,Chicago,IL,USA.3*ScienceDivision,NewYorkUniversityAbuDhabi,UAE.

*Jointcorrespondingauthors.E-mails:bedoor@;talal.rahwan@

Abstract

ArtificialIntelligence(AI)hasbecomeadisruptivetechnology,promisingtograntasignificanteconomicandstrategicadvantagetothenationsthatharnessitspower.China,withitsrecentpushtowardsAIadoption,ischallengingtheU.S.’spositionasthegloballeaderinthisfield.GivenAI’smassivepotential,aswellasthefiercegeopoliticaltensionsbetweenthetwonations,anumberofpolicieshavebeenputinplacethatdiscourageAIscientistsfrommigratingto,orcollaboratingwith,theothercountry.However,theextentsofsuchbraindrainandcross-bordercollaborationarenotfullyunderstood.Here,weanalyzeadatasetofover350,000AIscientistsand5,000,000AIpapers.Wefindthat,sincetheyear2000,ChinaandtheU.S.havebeenleadingthefieldintermsofimpact,novelty,productivity,andworkforce.MostAIscientistswhomigratetoChinacomefromtheU.S.,andmostwhomigratetotheU.S.comefromChina,highlightinganotablebraindraininbothdirections.Uponmigratingfromonecountrytotheother,scientistscontinuetocollaboratefrequentlywiththeorigincountry.Althoughthenumberofcollaborationsbetweenthetwocountrieshasbeenincreasingsincethedawnofthemillennium,suchcollaborationscontinuetoberelativelyrare.Amatchingexperimentrevealsthatthetwocountrieshavealwaysbeenmoreimpactfulwhencollaboratingthanwheneachofthemworkswithouttheother.Thesefindingssuggestthatinsteadofsuppressingcross-bordermigrationandcollaborationbetweenthetwonations,thefieldcouldbenefitfrompromotingsuchactivities.

SignificanceStatement

ThemassivepotentialofArtificialIntelligence(AI)toshapeglobalcompetitiveness,coupledwiththefiercegeopoliticaltensionsbetweenChinaandtheU.S.,haveledtopoliciesthatdiscouragecross-bordercollaborationandmigrationinthefieldofAI.Byanalyzing350,000AIscientistsand5,000,000AIpapers,wefindevidenceofanotablebraindrainbetweenthetwonations.However,uponmigratingfromonecountrytotheother,scientistscontinuetocollaboratefrequentlywiththecountryoforigin.Despitethese,ChinaandtheU.S.rarelycollaborate,butwhentheydo,theyproducemoreimpactfulresearchcomparedtowheneachworkswithouttheother.ThesefindingssuggestthattheAIfieldmaybenefitfrompromoting,ratherthandiscouraging,cross-bordercollaborationandmigration.

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Introduction

Artificialintelligence(AI)hasbecomeadisruptivetechnologywithfar-reachingeconomic,social,politicalandregulatoryrepercussions.Recentadvancesinroboticsandautomationcontinuetoreshapelocallabormarketsandtheglobalemploymentlandscape[

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,

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,

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,

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,

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,

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].Inhealthcare,machinelearningalgorithmssupporttheglobalresponsetopandemicoutbreaks[

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],transformingthemedicalimageanalysisfield[

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,

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],andmakingdrugdiscoveryfaster,cheaper,andmoreeffective[

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].Ontheroad,autonomousvehiclesholdthepromiseofimprovingtrafficflow,reducingpollution,andpreventingtrafficaccidentsthatresultfromhumanerror[

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,

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,

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].Indecisionmaking,algorithmsarepoisedtoaddresssomeofthemajorsocietalchallengesoftoday,e.g.,byreducinggenderbiasinhiringdecisions[

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,

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],droppingcrimerateswithmoreinformedbail[

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]andenforcementdecisions[

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],andimprovingthewaysocietiesaregoverned[

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].AIcanevenbehelpfulinthefightagainstcorruption,withseveralgovernmentsandnon-governmentalorganizations(NGOs)implementingAI-basedanti-corruptiontoolsthatenablecitizenstokeeptheirbureaucraticofficialsincheck[

19

].However,despiteitspotential,theperilsofAIaretooconsequentialtoignore.Althoughartificiallyintelligentsystemsmayreducehumanerror,theymayalsoexacerbatediscriminationagainstminoritiesbytargetingdisadvantagedgroupsortrainingondatathatreflectsystematicandpersistentbiases[

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,

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,

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,

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,

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,

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].Moreover,maliciousAIsystemsmaydisruptpeaceandinciteviolencebyspreadingfalseinformation[

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,

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,

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]orincreasingthethreatofterrorismandautonomousweapons[

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,

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,

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].

Notwithstandingitsperils,thetechnologiesdrivenbyAIarelikelytounderpinthesecurity,prosperity,andwelfareofthenationsthatharnessthem[

32

].Givenitspotentialtoshapeglobalcompetitiveness,theraceforworldleadershipinAIadoptionisintensifyingglobally,withcountriesdevelopingnationalAIstrategiesinanefforttoguideandfosteritsdeploymentthroughtargetedinvestmentsandstrategiccollaborations[

33

].China’sNewGenerationAIDevelopmentPlan[

34

]manifestsitscommitmenttowardsmakingAIthedrivingforcebehinditsindustrialandeconomictransformationby2025,andmakingChinaoneoftheworld’sprimaryAIinnovationcentersby2030[

35

].AccordingtothelatestreportbytheU.S.’sNationalSecurityCommissiononAI,theU.S.couldloseitstechnologicalpredominance—thebackboneofitseconomicandmilitarypower—toChina,andshouldmobilizeitsintellectualsandalliestoshiftthetidesinitsfavor[

36

].TheEuropeanUnion,ontheotherhand,isplanningtospendbillionsofeurostobuildatalentpipelineandfundresearchaspartofitsCoordinatedPlanonAI[

37

].AlthoughitisnotyetclearwhotheultimateleaderintheAIarenawillbe,thatleadermaywellbecometheworld’snextsuperpower[

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,

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].

ThisstudyfocusesonscientificcollaborationsbetweenChina-basedandU.S.-basedscientistsinthefieldofAI.Therationalebehindthisdesignistwofold.First,theemergenceofChinaasaleadingna-tioninscience[

40

,

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]ischangingtheglobalbalanceofpowerandchallengingtheU.S.’sdecades-longdominanceinscientificproduction[

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,

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].In2020,forexample,ChinaproducedthelargestvolumeofScienceandEngineeringpublicationsworldwide(23%ofglobaloutput)followedbytheU.S.(16%)[

44

].Moreover,thetwocountriesareleadingintermsoftheamountspentonresearchanddevelopment(R&D),e.g.,in2019theU.S.wastheworld’sleader($656billion)followedbyChina($526billion),withtheirexpendituresrepresenting27%and22%oftheglobaltotal,togetherrepresentingnearlyhalfoftheworld’sR&Dthatyear[

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].ThegapbetweenthesetwocountriesandtherestoftheworldisevenmorestarkwhenconsideringAIventurecapitalfundingin2020,as82%oftheyear’sglobalinvestmentinthissectorwenttostartupsintheU.S.($27.6billion)andChina($16.9billion)[

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].Aswewilldemonstratehere,ChineseandU.S.AIresearchresideattheforefrontAIresearchintermsofnoveltyandimpact.

ThesecondreasonisthefiercegeopoliticaltensionsbetweentheU.S.andChina,whichhavebecomemanifestinacademiatoshapeglobalcollaboration.Consider,forexample,thepoliciesandinvestigations

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launchedundertheTrumpadministration,including(i)theChinaInitiative—aprogramlaunchedin2018bytheU.S.DepartmentofJusticetocounterChinesenationalsecuritythreats,withaparticularemphasisonintellectualpropertyandtechnology[

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],and(ii)theinvestigationofhundredsofscientistsbytheNationalInstitutesofHealthin2018[

48

],withthemajorityofinvestigatedcasesinvolvingreceiptofresourcesfromChina[

49

].Inarecentstudy[

50

],Jiaetal.foundamarkeddeclineinthefrequencyofU.S.-Chinacollaborationsinthelifesciencesfollowingtheseinvestigations.Theauthorsinterviewedanumberofscientistswhohadpast,ongoing,orplannedcollaborationswithChina-basedinstitutions;thosescientistsconfirmedthat,duetotheinvestigationsmentionedabove,theywerereluctanttostartneworcontinueexistingcollaborationswithinstitutionsinChina.OtherrecentpoliciesthatcouldpotentiallylimitscientificcollaborationsbetweenthetwonationsincludetheEvaluationofRepresentativeOutcomes(ERO)releasedbytheChinesegovernment’sMinistryofScienceandTechnologyin2020[

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],whichencouragesscholarsinChinatopublishindomesticjournalsanddownplaystheimportanceofinternationaljournals[

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],indirectlyhinderingcross-bordercollaborations.

TheseobservationsmotivatetheexaminationofAIpapersproducedbytheU.S.andChina,withaparticularattentiontothoseresultingfromcollaborationbetweenthetwocountries.Here,weanalyzeadatasetofAIpapersandscientiststoaddressthefollowingquestions:(i)HowdotheU.S.andChinarankgloballyintermsofAInovelty,productivity,andimpact?(ii)Doscientistswhomigratefromonecountrytotheothercontinuetocollaboratewithcoauthorsfromtheorigincountry?Ifso,atwhatrate?(iii)AreresearchersfromtheU.S.andChinamoreimpactfulwhencollaboratingtogether?Andhasthischangedwiththeemergenceofpoliciesdesignedtodisruptcollaboration?

Results

RoleoftheU.S.andChinainAIresearch

WestartouranalysisbyexploringthecountriesthatleadglobalAIresearch.Tothisend,weutilizeMicrosoftAcademicGraph(MAG)[

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],awidelyuseddatasetcontainingdetailedrecordsofover263millionscientificpublicationsauthoredby271millionscientists.GivenourfocusonAIresearch,wefocusonpaperswiththeAIfieldofscienceclassificationaccordingtoMAG.ForeachAIpaper,weconsiderthecountrywhereoflastauthor’saffiliationasthatpaper’scountryoforigin.Thisisbasedontheconventionthatthelastauthoristypically“theheadofthelabthathostedmostoftheresearch”[

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].TocomparecountriesintermsofAIresearch,wefocusonfouroutcomemeasures:productivity,impact,novelty,andnumberofscientists.Inparticular,wemeasureproductivityasthenumberofAIpapersproducedbythecountry.FollowingAlSheblietal.[

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],weassessimpactasthenumberofcitationsthatAIpapersfromthecountryhaveaccumulatedwithinthefirsttwoyearspostpublication.WequantitynoveltyusingthemeasureproposedbyUzzietal.[

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,

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].Intuitively,foranygivenpaper,themeasureconsidersallpairsofjournalsreferencedtherein,andforeachpair,quantifiesthelikelihoodofthembeingco-cited.Ifthislikelihoodismuchlessthanexpectedbyrandomchance,thisisasignthepaperisnovelinthewayitbuildsonpreviouswork.Finally,tomeasurethenumberofAIscientistswhoresideinanygivencountry,wefirstidentifyAIscientistsfollowingtheapproachofAlSheblietal.[

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].Inparticular,weusetheMAGdataset,andclassifyeachpublishingresearcherasanAIscientistiftheyauthoredatleastthreepapers,themajorityofwhichareclassifiedasAIpapers.ThenumberofAIscientistsinanygivencountryistakenasthenumberofthosewhoseaffiliationresidesinthatcountry.Weanalyzetheseoutcomemeasuresbetweentheyears2000to2020(inclusive),resultinginadatasetof5,399,828papersand362,929scientists.Note,however,thatweonlymeasureimpactuptotheyear2018,toallowforcitationstoaccumulateduringthe

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twoyearspostpublication.

Figure

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adepictsthetotalAIproductivityofthe20mostproductivecountries.Ascanbeseen,theU.S.hasproducedatotalof1,365,452AIpapers(25.23%ofglobaloutput)whileChinahasproducedatotalof957,840papers(17.70%ofglobaloutput),demonstratingtheirglobaldominanceofAIproductivity.WhenlookingattheannualproductivityoftheU.S.andChinaovertime,wefindthatChinacaughtupwiththeU.S.bytheyear2010,buthasfallenslightlybehindinyearsthatfollowed.Figure

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bfocusesonthenumberofAIscientistsineachcountry,showingthatChinaisleadingwith105,103scientists,comparedtothe94,363intheU.S.ThisisduetoChina’ssubstantialgrowthinAIscientistsoverthelast5years,asshownwhenplottingthesenumbersovertime.Figure

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cpresentsthe20countrieswiththehighestimpactinAIresearch.WefindthattheU.S.andChinaleadthepackwithatotalimpactof7,368,464and2,157,122citations,respectively.Takentogether,thesecitationsamountto46.4%ofglobalimpact.Lookingataverageimpactperpaperovertime,weobserveanoverallupwardtrajectoryinaverageimpactovertimeforboththecountries.Togaindeeperinsights,weinvestigatethecountrieswiththelargestshareof“hits”basedonimpact,whereahitistakenasapaperthatfallsamongthe1%ofmostimpactfulpaperspublishedinthatyear[

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].Figure

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dillustratesthattheU.S.hasthelargestshareofAIhits(43.9%ofglobalhits),followedbyChina(10.9%).Lookingattheeachcountry’sshareperannum,wefindthatChina’sshareofhitshasincreasedovertime,whiletheU.S.haswitnessedaslightdeclineinitsshare.Figure

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eshowsthattheU.S.andChinaarealsoattheforefrontintermsofnovelty.Whenexaminingnoveltyovertime,wefindthattheaveragenoveltyofChina-basedpapershasbeencomparableto,ifnotgreaterthan,thatofU.S.-basedpapersoverthepasttwodecades.Figure

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fdepictseachcountry’sshareofnoveltyhits(i.e.,shareofpapersthatfallamongthe1%mostnovelpapers).Ascanbeseen,theU.S.andChinahavethelargestshares(23.2%and20.3%,respectively).Whenexaminingthesharesofthesecountriesovertime,wefindthatChinahascaughtupwiththeU.S.inrecentyears.

Migrationandcross-borderAIcollaborations

OurexploratoryanalysishasshownthattheU.S.andChinaareleadinginAIresearch.OurnextanalysisfocusesonAIscientistsmigratingtothesetwocountries.Figure

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aexaminesthedistributionofcountriesfromwhichAIscientistsmigratedtotheU.S.duringthepast20years,showingthatmostofthemcomefromChina.Moreover,thenumberofAIscientistsmigratingfromChinatotheU.S.hasbeenincreasingrapidlyoverthepastdecade.Similarly,asshowninFigure

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b,thecountryfromwhichAIscientistsmigratethemosttoChinaistheU.S.,andthenumberofsuchmigrationshasbeenincreasingsteadilyoverthepasttwodecades.Figures

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cto

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eshowthatChinaisattractingAIscientiststhataremoreexperienced,moreimpactful,andmoreproductivethanthoseattractedtotheU.S.ThesefiguresalsoshowthatChina-basedscientistswhomigratefromtheU.S.havegreaterexperience,impact,andproductivitythanthosewhodonot;thesameholdsforU.S.-basedscientistswhomigratefromChinacomparedtothosethatdonot.

Finally,wecompareChina-basedAIscientistswhomigratefromtheU.S.tothosewhodonot,intermsofthetherateatwhichtheycollaboratewithU.S.-basedcoauthorsafterthemigrationtookplace.Likewise,wecompareU.S.-basedscientistswhomigratefromChinatothosewhodonot,intermsoftherateatwhichtheycollaboratewithChina-basedcoauthors.ThecomparisoniscarriedoutusingCoarsenedExactMatchingwhilecontrollingfor(i)careerage,(ii)productivityintheyearofmigration,and(iii)citationsaccumulatedbytheyearofmigration.Eachmatchingexperimentcomparesthecontrolgroup(scientistsincountryAwhomigratedfromcountryB)tothetreatmentgroup(scientistsinAwhodidnotmigratefromB)intermsofpercentageoftheircollaboratorsthatinvolvecoauthorsfromBintheyearsfollowingthemigration.ThetwomatchingexperimentsandtheiroutcomesareillustratedinFigure

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f;seeSupplementaryTable1fornumericvalues.

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Asshowninthisfigure,China-basedAIscientistswhomigratefromtheU.S.arenearly20timesmorelikelytocollaboratewithU.S.-basedcoauthors,comparedtotheircounterpartswhodidnotmigratefromtheU.S.(54.45%vs.2.78%).Similarly,thelikelihoodofU.S.-basedAIscientistswhomigratefromChinatocollaboratewithChina-basedcoauthorsisnearly30timesgreater,comparedtotheircounterpartswhodidnotmigratefromChina(42.21%vs.1.46%).ThesefindingssuggestthattheexchangeofAIscientistsbetweentheU.S.andChinahasbroughtaboutprolificcollaborationsfromwhichbothnationshavebenefit.

CollaborativeAIresearchbetweentheU.S.andChina

Ourfinalanalysisfocusesonpapersproducedwhenthetwocountriescollaborate,andcomparesthemtothoseproducedwheneachcountryworkswithouttheother.Tothisend,foranygivenpaper,ifthelastauthorisaffiliatedwithaninstitutionfromtheU.S.,andatleastonecoauthorisaffiliatedwithaninstitutionfromChina,weconsiderthistobeaU.S.-basedpaperincollaborationwithChina.Similarly,ifthelastauthorhasaChina-basedaffiliation,andatleastonecoauthorhasaU.S.-basedaffiliation,weconsiderthistobeaChina-basedpaperincollaborationwiththeU.S.ThisapproachissimilartotheoneusedbyAlSheblietal.[

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],exceptthattheyfocusoncities,whileourfocusisoncountries.

Figure

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comparesU.S.-basedpapersproducedincollaborationwithChina,denotedby(US,China),tothoseproducedwithoutsuchcollaboration,denotedby(US,-China).ItalsocomparesChina-basedpapersproducedincollaborationwiththeU.S.,(China,US),tothoseproducedwithoutsuchcollaboration,(China,-US).Morespecifically,Figure

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adepictsthenumberofsuchpapersovertime.Ascanbeseen,collaborationsbetweentheU.S.andChinainthefieldofAIwerealmostnonexistentbefore2010,andstartedincreasingintheseconddecadeofthemillennium.Despitethisincrease,collaborationsbetweenthetwocountriescontinuetorepresentonlyasmallfractionoftheiroverallAIproductivity.

Figure

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bcomparesthenumberofauthorsonthesepapers.Asshowninthisfigure,teamsthatinvolvecollaborationsbetweenthetwocountriesare,onaverage,largerthanthosethatdonot.Figure

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ccomparesthesepapersintermsofthepercentageoflast-authoraffiliationsthatfallamongthetop100mostimpactfulinstitutionsinthefieldofAI;theseinstitutionsarelistedinSupplementaryFigure1.Ascanbeseen,thelastauthorismorelikelytobeaffiliatedwithatop-100institutionwhenthepaperinvolvesacollaborationbetweenthetwocountries.

Figure

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ato

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cimplythat,whencomparingtheimpactofpapersthatinvolveacollaborationbetweentheU.S.andChinatothosethatdonot,oneneedstocontrolforpublicationyear,teamsize,andlast-authoraffiliation.Tothisend,weuseCoarsenedExactMatching(CEM)[

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].Thematchingprocessisillustratedintheleft-handsideofFigure

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d,showingthattheimpactofpapersin(US,China)iscomparedtotheimpactofpapersin(US,-China)thathavethesamepublicationyear,teamsize,andlast-authoraffiliation.Likewise,theimpactofpapersin(China,US)iscomparedtotheimpactofthosein(China,-US)whilecontrollingfortheaboveconfounders.Theright-handsideofFigure

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ddepictstherelativedifferenceinimpactbetweenthepapersandtheirmatchedonesovertime;seeSupplementaryTables2and3forthenumericvalues.Ascanbeseen,fortheentiretyoftheperiodconsideredinouranalysis(2005to2018).China-basedpapersthatinvolveU.S.-basedcollaboratorshavebeenconsistentlymoreimpactfulthanthosethatdonot.AsforU.S.-basedpapers,thefirstdecadeinouranalysisshowsnodifferenceinimpactwheninvolvingChina-basedscientists.However,thelastfouryearsshowasignificantincreaseinimpactassociatedwithcollaboratorsfromChina.ThefigurealsoshowsthatChinawasbenefitingmorefromthesecollaborationsthantheU.S.,upuntil2015,afterwhichtheimpactgainassociatedwithcollaborationbecamesimilarforbothcountries.

OnepossibleexplanationbehindtheobservedincreaseinimpactwhentheU.S.andChinacollaboratecouldbeselectionbias.Inparticular,suchcollaborationsincuracommunicationcostduetothetime

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differencebetweenthetwocountries.Asaresult,collaboratorsworkingonpromisingideasaremorelikelytopersevereandseethepaperthrough,whilethoseworkingonlesspromisingideasarelikelytogiveupontheprojectandturntheirattentiontootheropportunities.TodeterminewhetherthismechanismexplainstheobservedincreaseintheimpactofChina-U.S.collaborations,weperformasimilaranalysis,butafterreplacingChinawithSouthKorea,andreplacingtheU.S.withCanada.TherationalebehindthisanalysisisthatcollaborationsbetweenChinaandtheU.S.enduretimedifferencescomparabletothoseenduredbycollaborationsbetweenSouthKoreaandCanada.Then,iftheaforementionedexplanationisvalid,wewouldexpecttoseesignificantlyhigherimpactwhenthelattertwocountriescollaborate.

OuranalysisfocusesonAIpaperspublishedbetweentheyears2015and2018—theyearsduringwhichChinaandtheU.S.weresignificantlymoreimpactfulwhentheycollaboratethanwhentheydonot.Additionally,itisunlikelythatresearchoutputduringtheseyearshasbeenaffectedbypoliciesdiscouragingU.S.-Chinacollaborations,insofarasthesepolicieswereannouncedonlylatein2018[

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,

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]orin2020[

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].OuranalysisusesCoarsenedExactMatchingtocompare(Canada,S.Korea)to(Canada,-S.Korea)andcompare(S.Korea,Canada)to(S.Korea,-Canada)intermsofimpact,whilecontrollingforpublicationyear,teamsize,andlast-authoraffiliation.ThesameanalysisisthenrepeatedbutforChinaandtheU.S.insteadofSouthKoreaandCanada.TheoutcomeofthisanalysisissummarizedinFigure

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;seeSupplementaryTable4fornumericvalues.Ascanbeseen,wefindnoevidencethatSouthKoreaandCanadaaremoreimpactfulwhencollaboratingtogether,whichcontradictstheexplanationsug-gestedearlier.ThisfindingsuggeststhatthereareotherfactorsdrivingtheobservedincreaseinimpactwhenChinaandtheU.S.collaborate.

Discussion

OurstudybelongstoagrowingbodyofworkthatfocusesonAIbibliometrics.Forexample,Franketal.[

60

]examinedresearchthatinteractswithAIusingtheMAGdatasettoidentifydisciplinesfrequentlycitingorcitedbyAIpapers.Similarly,Tranetal.[

61

]examinedAIdynamicsinmedicine,analyzingdiseasesmostfrequentlystudiedmostandleastinAIusingtheWebofScience.Martnez-Plumedetal.[

62

]identifiedtheresearchcommunitiesmostlikelytoadvancethestateoftheartinAIusingPapersWithCode—arepositoryofAIbenchmarksalongwiththeirassociatedpapers.Inrelatedresearch,Tangetal.[

63

]gainedinsightintohowthepaceofAIinnovationshaschangedoverthepastyearsbyanalyzingpreprintsonarX.Klingeretal.[

64

]identifiedtheAIsubfieldsmostinvolvedinthedevelopmentofExplainableAI—anareaofresearchthatfocusesonmakingAI-baseddecisionsmoreunderstandabletohumansusingbibliometricdatafromScopus.Finally,StathoulopoulosandMateos-GarciaprobedgenderdifferencesintheauthorshipofAIpapers[

65

].Despitethesevarioustopics,internationalcollaborationsingeneralandU.S.-Chinacollaborationsinparticularhavenotbeenexaminedtodate.

Ourstudyalsocontributestoanotherlineofresearchthatanalyzesthemobilityofscientists.Inpar-ticular,somescholarshavemodelledthisphenomenon[

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,

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,

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]andidentifiedfactorsthatinfluencescientists’migrationdecisions[

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,

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,

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,

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],whileothershavefocusedontheimpactofmigrationonscientists’careers[

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,

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