2025全球人工智能领域青年科学家分布与流动研究（英文）

Reportonthe

Distributionand

MobilityofGlobal

YoungAIScientists2025

世界青年科学家联合会

2025年10月

WorldAssociationofYoungScientistsOCT,2025

Internalreportforreferenceonly

EditorialTeam

ReportPlanning:YangDaiqing,GaoJiping,WangYunhong

Authors:LiBohui,WangYunhong,YeXianting

Reviewers:WangYunhong,ZhengChuhua,ZhangAixia

TechnicalTeam:TianRuiqiang,MaChen,YangXiao,XuXiaoyang

ExpertTeam:LiuXiaojuan,WuyunQiqige,ZhongZurong,ZuoXiaoli

CompilingOrganization:InstituteofScientificandTechnicalInformationofChina,Scientometrics&EvaluationResearchCenter

Introduction

Withgroundbreakingadvancesincutting-edgefieldslikedeeplearningandlarge-scalemodels,artificialintelligence(AI)isreshapingresearchparadigmsandindustriallandscapesworldwide.Youngscientistsarecurrentlyataprimestageforacademicinnovationandcareergrowth.Theynotonlyformthebackboneofknowledgecreationandfrontierexploration,butalsoserveaskeydriversandcommunicatorsoftherapidevolutionandtransformativeapplicationsofAItechnologies.

Youngscientistsareuniquelypositionedtotranscendgeographicalandculturalboundaries,buildingtrustandfosteringcollaborationacrossborders.Thiscapabilityisessentialfortheglobalcommunitytobuildconsensusoncriticalissuessuchasdatasecurityandethicalstandards,tacklesharedchallenges,andpromoteamoreequitableandinclusiveglobalgovernanceframework.Adeepunderstandingofthescale,structure,distribution,collaboration,mobility,andgrowthofyoungAIresearchersoffersvaluableinsightsintothetalentstrategiesofdifferentcountriesandservesasafoundationforassessingtheglobaldevelopmentofAIresearch.

Throughin-depthanalysisofthegeographicaldistribution,mobilitypaths,andinternationalcollaborationcharacteristicsofyoungscientistsworldwide,thisreportaimstohelppolicymakersunderstandregionaltalentdevelopmentwithinaglobalcontextandofferinsightsfordevelopingclearerandmoreeffectivestrategies—includinghowtoidentifycomparativeadvantagesandstrengtheninternationalcooperation.

Ultimately,thisreportaspirestocontributetotheglobalcultivationandsustainabledevelopmentofAItalent.

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I

KeyFindings

YoungScientistsAreHighlyConcentratedinaFewCountries:Top10CountriesAccountforOver80%oftheTotal

TheglobaldistributionofyoungAIscientistsishighlyconcentrated,withthetop10countriesaccountingforover80%ofthetotaltalentpool.Chinaleadswithmorethan50,000researchers,followedbytheUnitedStates.India,England,Germany,andothernationsalsofeatureprominently.Collectively,ChinaandtheUnitedStatesrepresentmorethanhalfofallyoungAIscientistsworldwide.

WithinChina,youngscientistsareprimarilyaffiliatedwithnationalresearchinstitutesandleadinguniversities.Thetop10hostinstitutionsare:ChineseAcademyofSciences,TsinghuaUniversity,ZhejiangUniversity,ShanghaiJiaoTongUniversity,PekingUniversity,UniversityofScienceandTechnologyofChina,TianjinUniversity,UniversityofElectronicScienceandTechnologyofChina,Xi’anJiaotongUniversity,andNorthwesternPolytechnicalUniversity

Over60%ofScientistswithMultipleMovesUltimatelyReturnHomeCountries

Overall,youngAIscientistspredominantlybuildtheircareersintheirhome

ReportontheDistributionandMobilityofGlobalYoungAlScientists2025

countries,withapproximately20%havingexperiencedcross-bordermobility.Internationalmobilityishighlyconcentrated,withthelargestandroughlybalancedbilateralmobilityoccurringbetweenChinaandtheUnitedStates,farexceedingthatofanyothercountrypair.BeyondChina–U.S.exchanges,therearealsosubstantialbidirectionalmobilitylinksbetweenChinaandcountriessuchasAustraliaandSingapore,whiletheUnitedStatesmaintainssignificantcross-borderexchangeswithEngland,Canada,andIndia.

Multiplemovesand“circularmobility”arecommonamongyoungAIscientists.Morethan60%ofthosewithmultipleinternationalmovesultimatelyreturntotheirhomecountries.Thissuggeststhatbraindrainisnotapermanentloss,butratheramanifestationofcyclicalresourceallocationonaglobalscale.

Around30%ofPapersInvolveInternationalCollaboration

ResearchactivitiesamongyoungAIscientistsarepredominantlycollaborative,withindividuallycompletedstudiesaccountingforonlyaverysmallproportion.Mostpapersexhibita“small-team”collaborationpattern,withthenumberofauthorstypicallyrangingfrom2to7,andboththeaverageandmediannumberofauthorsbeingfour.

Intermsofauthorshiproles,mostyoungscientistsparticipateas“co-authors,”indicatingthattheytendtoplaysupportingorexecutingroleswithintheirresearchteams.Atthesametime,asignificantportionofthemserveasbothfirstandcorrespondingauthors,showingthatyoungAIresearchersoftenleadprojectswhileremainingdeeplyinvolvedinfrontlineresearch.

Intermsofinternationalcollaboration,about30%ofallpapersinvolvecross-borderpartnerships,withChina–U.S.collaborationstandingoutprominently,farexceedingthatofanyothercountrypair.

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I

Contents

1BackgroundandObjectives 1

1.1BackgroundandSignificance 2

1.2ResearchObjectives 3

2LiteratureReview 5

2.1ReviewofResearchonAITalent 6

2.2ConceptandDefinitionStandardsofYoungResearchers 8

2.3DefinitionPrinciplesandMethodsforResearchSubjectsinThis

Report 10

3DataandMethodology 11

3.1DataSources 12

3.2DataPreparation 12

3.3IdentificationofResearchSubjects 15

3.4ResearchMethods 17

4PublicationOutputofGlobalYoungAIScientists 19

4.1OverallPublicationVolumeShowsRapidGrowthAfter2015 20

4.2AveragePublicationOutputperResearcheris6,Primarilyin

ConferencePapers 21

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ReportontheDistributionandMobilityofGlobalYoungAlScientists2025

5NationalandRegionalDistributionofGlobalYoung

AIScientists 23

5.1GlobalDistributionAreHighlyConcentratedinTop10Countries.24

5.2ChineseInstitutionsAreConcentratedinNationalResearch

InstitutesandTopUniversities 25

6Cross-BorderMobilityofGlobalYoungAI

Scientists 27

6.1AnalysisofCross-BorderMobilityScale 28

6.2AnalysisofCross-BorderMobilityDirections 30

6.3AnalysisofCross-BorderMobilityPaths 33

7CollaborationPatternsandAuthorshipRolesof

YoungScientists 39

7.1MostCollaborationsInvolveTeamsofFewerThanTenPeople 40

7.2YoungResearchersContinueDeepInvolvementinFrontline

ResearchWhileLeadingProjects 41

7.3About30%ofPapersInvolveInternationalCollaboration 42

1

BackgroundandObjectives

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ReportontheDistributionandMobilityofGlobalYoungAlScientists2025

1.1BackgroundandSignificance

Artificialintelligence(AI)isastrategictechnologyspearheadinganewwaveofscientificandindustrialrevolution,positioningitselfasakeyfrontierandastrategicpriorityformajorcountriesglobally.Enabledbyparalleladvancesinalgorithms,computingpower,anddataavailability,AIhasachievedleapfrogprogressandisprofoundlyreshapingresearchparadigms,industrialstructures,andsocietalproductionandlifestyles.

YoungscientistshavebecomecentraldriversofAIinnovation.TheyarenotonlyactiveinacademiabutalsodeeplyengagedinindustrialR&Dandreal-worldapplications.Understandingtheirgeographicdistribution,mobilitypaths,andcollaborationcharacteristicsisthereforeofconsiderablerelevanceandpracticalsignificance.

AItalentdevelopmentisnowamajorconcernfordomesticandinternationalscholars,internationalorganizations,governmentagencies,andacademicinstitutionshavealsoreleasedvariousreportsonAItalent,providingin-depthanalysesofitsoverallscale,geographicdistribution,trainingmechanisms,mobilitytrends,andcompetitivelandscape.ThesestudiesofferimportantreferencesforunderstandingtheglobaldevelopmentofAItalent.However,comparedwiththebroaderresearchpopulation,youngscientistsexhibitdistinctcharacteristicsintermsofresearchoutput,collaborationpatterns,internationalmobility,andacademiccareerpaths.MostexistingstudiesfocusontheoverallAIworkforceortop-tiertalent,whilesystematicanalysesspecificallytargetingyoungAIscientistsremainnoticeablyinsufficient.

Thisreportleveragespublicationdatafromtop-tierAIjournalsandconferences,combinedwithinformationonauthors'educationalbackgrounds,researchoutput,andcareerhistories.Usingscientometricanalysisandmachinelearningmethods,itsystematicallyidentifiesandfiltersacohortofyoungscientistsagedapproximately45andbelow.Buildingonthisfoundation,thereportanalyzestheirgeographicaldistribution,mobilitypathways,andcollaborationpatterns,aimingtoprovidedata-driveninsightsandreferencesforadeeperunderstandingofthegloballandscapeofyoungAIscientists.

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1

BackgroundandObjectives

1.2ResearchObjectives

ThisreportleveragesextensivebibliometricandcareerprofiledataofyoungAIscientiststoestablishananalyticalframeworkforassessingthedevelopmentlandscapeofyoungAIscientistsglobally.Itaimstodelivermultidimensionalinsightscoveringgeographicdistribution,talentmobility,andinternationalcollaboration.Thespecificobjectivesincludethefollowingthreeaspects:

Firstisunderstandingtheglobaldistributionpattern.Byanalyzingtheinstitutionalaffiliationsofpaperauthors,thisreportsystematicallydelineatesthedistributionofyoungAIscientistsacrosscountriesandregions.

Secondisanalyzingtalentmobilitypatterns.Throughlongitudinaltrackingofauthors'institutionalaffiliations,thisreportvisualizescross-bordermobilitypathsofyoungAIscientists.

Thirdisidentifyingresearchcollaborationpatterns.Utilizingco-authorshipdata,thisreportanalyzescollaborativepracticesamongyoungAIscientists,withfocusoncollaborationscale,authorroles,andinternationalpartnershippatterns.

2

LiteratureReview

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ReportontheDistributionandMobilityofGlobalYoungAlScientists2025

2.1ReviewofResearchonAITalent

Inrecentyears,AItalenthasemergedasacriticalglobalfocus.Numerousauthoritativeinstitutionshavepublishedreportscontinuouslytrackingandanalyzingthedistribution,development,andmobilityofAItalentacrosscountries,regions,andprofessionaltiers.TsinghuaUniversity’sAminerplatform,forinstance,ranksleadingAIresearchersbasedonauthordatafromtop-tierjournalsandconferencesacross20coreAIfieldsoverthepastdecade,selecting2,000individualsforitsannuallistoftopAItalents.1In2024,MacroPolo(underthePaulsonInstitute)releasedtheGlobalAITalentTracker,whichsamplesauthorsfromNeurIPSasaproxyforeliteAItalentandincorporatesCVdatatoexaminetheircareertrajectoriesandgeographicdistribution.2Draup’sViewonGlobalAITalentLandscape(late2024)analyzesworldwidetalentdistribution,careerpaths,compensation,teamstructures,andmobilityusingacombinationofcareerprofilesandrecruitmentdata.

3TheUK-baseddatacompanyZekiDatareleasedtworeports—AIMoneyball4andTheStateofAITalent

20255—whichanalyzethecharacteristicsandcareertrajectoriesof2,000topAIprofessionals,aswellastheoverallcompetitivelandscapeofglobalAItalent.TheInternationalFinanceForum(IFF)releasedPartIIIofIFFGlobalArtificialIntelligenceCompetitivenessIndexReportin2025,offeringacomprehensiveanalysisofAItalentdistributionandmobilityacross20countries.6StanfordHAI’s2025AIIndexReport(8thedition)includesanin-depthlookatAItalenttraining7,whiletheU.S.CouncilofEconomicAdvisersissueditsownAITalentReportinFebruary20258.Takentogether,thesereportsprovideamulti-dimensionalandauthoritativeoverviewoftheglobalAItalentlandscape.

Intermsofgeographicaldistribution,differentstudieshavereachedvaryingconclusionsduetodifferencesindatasourcesandstatisticalcriteria.IndustryreportsgenerallyindicatethattheUnitedStatesleadsinboththequantityandqualityofAItalent,whilestudiesbasedonpublicationdatahighlightChina’sstrengthsinresearchoutputanditsgrowingpoolofyoungscientists.Overall,globalAItalentishighly

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/ai2000/about/introduction

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/press_release/study-finds-us-remains-a-magnet-for-worlds-best-and-brightest-ai-talent-but-more

-global-talent-are-staying-home-instead-of-going-abroad/

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/wp-content/uploads/2025/01/15055404/3.0-Draup_Global-AI-Report_

compressed-1.pdf

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/report/ai-moneyball/

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/dist/2025/07/AIEP3/%E5%9B%BD%E9%99%85%E9%87%91%E8%9E%8D%E8%AE

%BA%E5%9D%9B%EF%BC%88IFF%EF%BC%89%E5%85%A8%E7%90%83%E4%BA%BA%E5%B7%A5%E6%99%BA%E8%83%BD%E7%AB%9E%E4%BA%89%E5%8A%9B%E6%8C%87%E6%95%B0%E6%8A%A5%E5%91%8A%20-%20

%E7%AC%AC%E4%B8%89%E7%AF%87.pdf

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/ai-index/2025-ai-index-report

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/cea/written-materials/2025/01/14/ai-talent-report/

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LiteratureReview

concentratedinahandfulofcountries,withtheUnitedStatesandChinastandingasthetwomajorcenters.

Fromanindustry-dataperspective,theUnitedStatesleadsinbothtalentquantityandquality.TheglobaldistributionofAItalentshowsastrongconcentrationtrend,withtheUnitedStatesandChinastandingasthetwomajorcenters.AccordingtoIFFGlobalArtificialIntelligenceCompetitivenessIndexReportreleasedbytheInternationalFinanceForum(IFF),thereareapproximately3millionAIprofessionalsworldwide,with33%basedintheUnitedStatesand22.4%inChina.Analysesfocusingontop-tiertalentfurtherindicatethattheUnitedStatescontinuestoholdaqualitativeedge.TheMacroPoloreportfindsthat57%oftheworld’stop2%ofAIexpertsarelocatedintheUnitedStates,comparedwith12%inChina.Similarly,datafromZekiDatasuggestthatmorethan70%offrontierAItalentisconcentratedintheUnitedStates.

StudiesbasedonpublicationdataemphasizeChina’sstrengthsinresearchoutputanditsreserveofyoungtalent.AccordingtoareportbyScience,Chinahasapproximately30,000AIresearchersacrossdifferentagegroups,comparedwitharound10,000intheUnitedStates—andChina’sAItalentpoolisoverallyounger1.Thisfindingalignswithseveralotherstudiesbasedonacademicpublications,whichlikewiseindicatethatChinaholdsarelativeadvantageinresearchoutputandthescaleofitsyoungtalent.

Intermsofgrowthtrends,theproportionoftop-tierAItalentoriginatingfromChinaisrisingrapidly.AccordingtoMacroPolodata,Chinaaccountedfor47%ofnewlytrainedworld-classAIresearchersin2022,asignificantincreasefrom29%in2019.Meanwhile,emergingmarketssuchastheUnitedArabEmirates,SaudiArabia,andBrazilaresteadilyexpandingtheirAItalentpools,whiletraditionaltechnologypowerhouses—includingtheUnitedKingdom,SouthKorea,Canada,andAustralia—continuetoplaykeyrolesintheglobalAItalentlandscapeandcompetition.

Intermsoftalentmobility,theUnitedStatesremainstheprimaryhubforhigh-levelAItalent,butitslong-standing“one-wayattraction”patternisweakening,givingwaytoanincreasinglymultipolarmobility.China,meanwhile,isgraduallytransformingfromamajor“talentexporter”intoa“two-wayhub,”demonstratinggreateroutputefficiencyinChina–U.S.researchcollaboration.

China,meanwhile,isgraduallytransformingfromamajor“talentexporter”intoa“two-wayhub,”demonstratinggreateroutputefficiencyinChina–U.S.researchcollaboration.AccordingtoresearchbyMacroPolo,Chinesenationalsaccountforasmuchas38%ofthetalentintopU.S.AIresearchinstitutions—roughlyonparwiththeproportionofAmerican-bornresearchers(37%).ThisindicatesthattheUnitedStatesremainstheworld’sleadingdestinationfortop-tierAIprofessionals.Atthesametime,MacroPolonotesthattheinflowandoutflowofAIPhDsintheUnitedStateshavenearlybalancedout,suggestingadeclineintheshareofresearcherschoosingtostaylong-termandsignalingtheendofAmerica’sonce-dominant“brain-drainmagnet”effect.

Concurrently,China’sattractivenessisgrowingrapidly.AstudypublishedinNatureobservedarisinginflowoftopAIscholarsintoChina,reflectingitstransitionfromapureexporteroftalenttoadual-flowhub

1Science.Chinatopsworldinartificialintelligencepublications:Databaseanalysisreveals[EB/OL].Science,(2025-07-11)[2025-09-26].

/content/article/china-tops-world-artificial-intelligence-publications-database-analysis-reveals

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thatbothexportsandattractstalent.1Chinaisnotaloneinthisshift—Indiashowsasimilarpattern:whilenearlyallIndianAIresearchersworkedabroadin2019,by2022one-fifthhadchosentoremainandworkinIndia.Together,thesedevelopmentsunderscoretheemergenceofamoremultipolarpatterninglobalAItalentmobility.

Intermsofinstitutionaldistribution,therearecleardifferencesacrosscountries.BoththeAminerAI2000rankingandMacroPoloreportsshowthatChina’stopAItalentislargelyconcentratedinleadinguniversitiesandresearchinstitutionssuchasTsinghuaUniversity,ZhejiangUniversity,andtheChineseAcademyofSciences.Incontrast,theUnitedStates’AIprofessionalsareprimarilyclusteredinmajortechnologycompaniessuchasGoogle,Microsoft,andMeta,reflectingitstraditionalstrengthinindustry-driveninnovation.

ThiscontrastalignswiththeglobaltrendofAIresearchincreasinglyshiftingtowardtheindustrialsector.StanfordUniversity’sAIIndexReport2024pointsoutthatindustryisnowtakingtheleadinfrontierAIresearch.AccordingtodatafromGeorgetownUniversity’sdatabase,3.56%ofallcomputersciencepaperspublishedgloballyinthepastfiveyearsincludedatleastoneindustry-affiliatedauthor.Amongthese,Chinesescholarscontributed23.58%,indicatingthattheresearchqualityandimpactofChineseenterprisesareimprovingrapidly.

Intermsofcareerdevelopmentpaths,topAItalentsshowremarkableconsistencyinboththeireducationalandprofessionalbackgrounds.ResearchbyZikiDatarevealsseveralsharedcharacteristics:First,theypossessstrongacademicfoundations—80%graduatedfromtheworld’stop50universities,withapreferencefordisciplinessuchascomputerscience,mathematics,andphysics.Second,theytendtohavehigh-qualityinternshipexperiences—thelikelihoodofhavinginternedatoneofthesevenmajortechgiants(includingGoogleandMeta)isthreetimeshigherthanthatofaverageAIprofessionals.Third,theyexhibitastrongerwillingnessforinternationalmobility,with60%expressinginterestinworkingabroad.

TheInternationalFinanceForum(IFF)ReportfurtherconfirmsthatAIprofessionalsworldwidearegenerallyhighlyeducated,withover88%holdingamaster’sdegreeorabove.SincethelaunchofChatGPTin2022,theAIindustryhasattractedalargeinfluxofyoungtalent,whohavebecomeakeydrivingforceinthesector’srapiddevelopment.

2.2ConceptandDefinitionStandardsofYoungResearchers

Toclarifythedefinitionof“youngresearchers,”thisstudysystematicallyreviewedpolicydocumentsissuedbygovernments,researchfundingagencies,andacademicorganizationsinvariouscountries,while

1AlShebliB,MemonSA,EvansJA,etal.ChinaandtheU.S.producemoreimpactfulAIresearchwhencollaboratingtogether[J].ScientificReports,2024,14:28576.DOI:10.1038/s41598-024-79863-5.

2LiteratureReview

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alsodrawingontheclassificationpracticesofexistingstudies.Thefindingsshowthatthereisnouniversallyacceptedinternationalstandardfordefining“youngresearchers,”butseveralcommonapproacheshaveemerged.

Thefirstapproachistheagelimit,whichisoftenspecifiedinyouthfundingortalentprograms.Forexample,China’sInternationalYoungTalentsProgramsetstheupperagelimitat45,servingasakeythresholdfortherecruitmentofhigh-levelyoungprofessionals.1InItaly,theMinistryofEducationandResearch(MUR)restrictsapplicantsforitsYoungResearchersProgramtothoseaged40orbelow,extendableto45iftheapplicantobtainedaPh.D.withinthepastsevenyears2.Similarly,Norway’sFRIPROYoungResearcherProjectrequiresapplicantstobenoolderthan403.

Thesecondapproachfocusesonyearsofprofessionalexperience,usuallycalculatedasthenumberofyearssinceearningaPh.D.Forexample,theEuropeanResearchCouncil(ERC)StartingGrantrequiresapplicantstohaveobtainedtheirdoctoraldegreewithin2to7yearspriortoapplication(tobeextendedto10yearsstartingin2027)4.Similarly,theU.S.NationalInstitutesofHealth(NIH)EarlyStageInvestigatorprogramlimitseligibilitytoresearcherswithin10yearsofearningtheirhighestresearchdegreeorcompletingpostgraduatetraining,providedtheyhavenotpreviouslyreceivedsubstantialindependentresearchfunding5.

Thethirdapproachconcernsemploymentstatus,specificallywhethertheresearcherhasobtainedapermanentposition.Forinstance,theEuropeanScienceFoundationdefines“earlycareerstage”researchersasthosewhohaveheldapermanentpositionfornomorethanfiveyears.IntheUnitedStates,theEarlyCareerResearchActdefinesearly-careerresearchersasthoseholdingtenure-trackassistantprofessorships6.

Thefourthapproachisbasedonresearchcareerduration,oftenmeasuredfromkeyacademicmilestonessuchasthetimeoffirstpublication,firstfirst-authorpaper,orfirstcorresponding-authorpaper.Forinstance,theyearinwhicharesearcherpublishestheirfirstpaperissometimesdefinedasthestartingpointoftheiracademiccareer.Inpractice7,thisapproachisoftencombinedwithcertainquantitativeorqualitativecriteria—suchasthenumberorimpactofpublications—todetermineeligibility.

Overall,thesefourapproacheseachhavedistinctcharacteristics:ageandyearssincePh.D.arestraightforwardtoimplement,whileemploymentstatusandresearchoutputmoreaccuratelyreflectsubstantiveacademicachievement.Inpractice,amulti-dimensionalcombinationoftheseindicatorsisoftenadoptedtostrikeabalancebetweenresearchfeasibilityandacademicsoundness.

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/Webpages/viewdetail.aspx?id=4063868720&

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https://www.unipd.it/en/mur-funding-young-researchers-2024

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https://www.forskningsradet.no/en/call-for-proposals/2023/researcher-project-young-talents-fripro/

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https://erc.europa.eu/apply-grant/starting-grant

5NIH.NewandEarlyStageInvestigatorPolicies[EB/OL].[2022-01-13].

/policy/early-stage/index.htm

6NiuPing

,MengXiangli,SuFen,etal.“StandardsandImplicationsof‘ResearchAge’and‘EarlyCareerStage’inYouthTalentFunding[J].”ChinaScienceFoundation,2013,27(1):4.DOI:CNKI:SUN:ZKJJ.0.2013-01-006.

7ZhangLihua,YaoChangqing.“TheImpactofRetractionEventsinEarlyResearchCareersonScientificPerformance[J].”ChineseJournalofScientificandTechnicalPeriodicals,2024,35(11):1510-1522.DOI:10.11946/cjstp.202407310838.

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2.3DefinitionPrinciplesandMethodsforResearchSubjectsinThisReport

Theresearchsubjectsofthisreportaredefinedas“youngscientists.”Aftersystematicallyreviewingrelevantinternationalanddomesticpracticesandconsideringdataavailabilityandcross-countrycomparability,thisreportadoptsathree-stepapproachtodefine“youngscientists,”establishingacomplementarymechanismbetweenagelimitsandpublicationcharacteristics.

Step1:Theterm“young”isuniformlydefinedas45yearsoldoryounger,abaselineconsistentwithwidelyacceptedinternationalpractices,disciplinarytrainingcycles,andtheneedforcross-countrycomparison.

Step2:Theagedefinitiondoesnotrelyonasingledimension;instead,itintegratesPh.D.graduationyearandpublicationcharacteristicstoaligncloselywiththe45-yearthreshold.ForindividualswithORCID-verifiedPh.D.graduationyears,theanalysisfollowstheU.S.NationalScienceFoundation’sSurveyofEarnedDoctorates(SED)1,whichindicatesanaveragePh.D.graduationageofaround30.Accordingly,graduationyearisconvertedintoanageindicator.Forlargegroupslackingbiographicaldata,aclassificationmodelistrainedusing20publicationbehaviorfeatures—includingpublicationtimeseries,authorroles,andoutputintensity—toestimatetheprobabilityofbeing“≤45yearsold.”Themodel’sthresholdisfine-tunedthroughcross-validationtoensureconsistencywiththeunifiedagecriterionacrosslargesamples.

Step3:Afteridentifyingage,aminimumacademicactivitylevelandbasicqualitythresholdareappliedtoensurethattheselectedpopulationisbothscientificallyactiveandacademicallycontributive.

Thisdefinitionframeworkestablishes45yearsoldastheunifiedagestandard,usesPh.D.graduationyearasthebaselinefordeterminingresearchsamples,andleveragesbehavioral-featuremodelingforlarge-scaledataexpansion—balancinginternationalcomparabilitywiththebreadthandrobustnessofclassificationresults.Unlessotherwisespecified,allsubsequentanalysesandfindingsinthisreportarebasedontheabovedefinitionof“youngscientists.”

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/surveys/earned-doctorates/2023#data

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DataandMethodology

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ReportontheDistributionandMobilityofGlobalYoungAlScientists2025

3.1DataSources

Thedatasourcesforthesampleofthisreportareasfollows:

(1)WebofScienceCoreCollection(WOSCore)publicationdata.Theretrievalwindowcoverstheperiodfrom2000to2025.BasedonWOSdisciplineclassifications,AI-relatedkeywords,andhigh-levelAIjournalsandconferencelistsrecommendedbytheChinaComputerFederation(CCF)andtheChineseAssociationforArtificialIntelligence(CAAI),thesearchwasrestrictedtodocumenttypesofarticle,review,orproceedingspaper.AsofJune24,2025,atota