nber -The Effect of Child Endowment on Fertility Choices-此為英文文檔

NBERWORKINGPAPERSERIES

THEEFFECTOFCHILDENDOWMENTONFERTILITYCHOICES

VictorLavy

YeshayaNussbaum

WorkingPaper31560

/papers/w31560

NATIONALBUREAUOFECONOMICRESEARCH

1050MassachusettsAvenue

Cambridge,MA02138

August2023

WebenefitedfromthecommentsandsuggestionsbyseminarparticipantsatUniversityofWarwick,EinaudiInstitute,EuropeanUniversityInstitute,HebrewUniversity,andTelAvivUniversity,andbyEmmaDuchini,JamesFenske,OmerMoav,JoramMayshar,MatteoParadisi,AnaliaSchlosser,andHannahTrachtman.WethanktheCentralBureauofStatisticsinIsraelforprovidingrestrictedaccesstosomeofthedatausedinthisstudy.TheviewsexpressedhereinarethoseoftheauthorsanddonotnecessarilyreflecttheviewsoftheNationalBureauofEconomic

Research.

NBERworkingpapersarecirculatedfordiscussionandcommentpurposes.Theyhavenotbeenpeer-reviewedorbeensubjecttothereviewbytheNBERBoardofDirectorsthataccompaniesofficialNBERpublications.

?2023byVictorLavyandYeshayaNussbaum.Allrightsreserved.Shortsectionsoftext,nottoexceedtwoparagraphs,maybequotedwithoutexplicitpermissionprovidedthatfullcredit,including?notice,isgiventothesource.

TheEffectofChildEndowmentonFertilityChoices

VictorLavyandYeshayaNussbaum

NBERWorkingPaperNo.31560

August2023

JELNo.I0,J10

ABSTRACT

Doestheintellectualendowmentofchildrenaffectparents’fertilitychoices?Thequantity-qualitymodeloffertilitypredictsthatapositive(negative)shocktochildendowmentincreases(decreases)parentaldemandforchildren.WetestthesepredictionsusingIsraelidataonintellectuallygiftedandintellectuallydisabledchildren.Becausefamilieswithanexceptional-endowmentchilddifferfromthosewithout,weproposequasi-experimentsthatexploitdifferencesinthechild’sbirthordertoestimatetheeffectofherbirthonfurtherfertility.Wefindthatthebirthofagiftedchildincreasesfamilysize.However,parentsmustrecognizetheendowment’sexceptionalityforittohaveaneffect.Similarly,thebirthofanintellectuallydisabledchildnegativelyaffectsfamilysize,butonlywhenthechildisofhighbirthorder.Ourresultspointtochildendowmentasanimportantfactorindeterminingfertilitychoices.

VictorLavy

DepartmentofEconomics

UniversityofWarwick

Coventry,CV47AL

UnitedKingdom

andHebrewUniversityofJerusalem

andalsoNBER

v.lavy@warwick.ac.uk

YeshayaNussbaum

DepartmentofEconomics

HebrewUniversityofJerusalem

Jerusalem,Israel

yeshaya.nussbaum@mail.huji.ac.il

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1Introduction

Families’fertilitychoices–decisionsonwhethertohavean(additional)childandregardingfamilysizeingeneral–areaffectedbyvariousfactors.Socialscientistshavedevelopedtheoriestyingdemandforchildrentotheopportunitycostofwomen’stime,socialnorms,andgovernmentpoliciesaffectingthecompatibilityofcareerandfamily,amongothers(Doepkeetal.,2023).StartingwithBecker(1960),economistssuggestedthatthedesiredlevelofchild“quality”isakeydeterminantoffertilitychoices.Ifso,howdochangesinthequalityendowmentofchildrenaffectparents’decisionsaboutfamilysize?

Inthecurrentpaper,weadopttheconceptualframeworkofthequantity-quality(QQ)modeloffertility(BeckerandLewis,1973;BeckerandTomes,1976),inwhichparentstradeoffthenumberofchildrenagainsttheirdesiredqualityofeachchildwhenchoosingfertility.Withinthisframework,weshowtheoreticallythatchangesinparents’expectationofthequalityendowmentoftheirchildrenactivatepriceandincomeeffectsthatimpactparents’demandforchildren.Sincethebirthofachildwithexceptionallyhighorlowendowmentinducesparentstoupdatetheirexpectationoftheendowmentleveloftheirchildren,itwillaffectfuturefertilitychoices.Themodelpredictsthatapositiveendowmentshock–thebirthofachildwithanexceptionallyhighendowment–willincreaseparentaldemandforchildren.Ontheotherhand,thebirthofachildwithanexceptionallylowendowmentwilldecreaseit.

Pastresearchhastestedthequantity-qualitymodeloffertilitybystudyingashocktoquantity,typicallybyexploitingthebirthoftwinsorsame-genderchildren,andgovernmentregulationonfamilysize,suchasChina’sone-childpolicy.Thecur-rentpapertakesanalternativeapproachbystudyingtheeffectofaqualityshockondemandforchildren.First,withinthequantity-qualityframework,weconceptualizeendowmentshockasthebirthofachildwithanextremelyhighorlowlevelofintel-lectualendowment.Then,usingasetofquasi-experiments,wetestthesepredictionsandestimatethereduced-formeffectofapositiveornegativechangeinendowmentonfamilysize.

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Thefirstexperimentestimatestheeffectofafirst-bornhigh-endowmentchildonfurtherfertilityinasampleincludingfamilieswitheitherafirst-orsecond-bornhigh-endowmentchildandatleasttwochildren.Similarly,inthesecondquasi-experiment,weestimatetheeffectofasecond-bornhigh-endowmentchildonfurtherfertilityinasampleincludingfamilieswitheitherasecondorthird-bornhigh-endowmentchildandatleastthreechildren.WeuseIsraelidataonfamiliesandtheirchildrenandmeasurehighendowmentbygiftednessorexceptionalscoresonearlycognitivetests.Wefindthatthebirthofahigh-endowmentchildincreasestheprobabilityofanadditionalchildinbothquasi-experiments.

Inaddition,astheinformationonchildendowmentbecomesnoisier,parents’abilitytorecognizetheendowmentbecomesaconditionforitseffect.Forthisreason,wepostulatethattheeffectofchildendowmentonfertilitydecisionsismoreevidentandmoresubstantialamongeducatedparents.First,educatedparentsmightbemoreobservantandawareofthesignsofgiftednessintheirchild.Forexample,aknowledgeableparentengagestheirchildmorewitheducationalgamesandactivities,suchasreadingbooksorsolvingpuzzles,whichprovidemoreopportunitiestonoticeexceptionaltalent.Second,aneducatedparentmaypreferqualityoverquantityofchildrenandrespondactivelytosignsofchildgiftedness.Third,weshowthathighlyeducatedfamiliesprimarilydrivethepositiveeffectofahigh-endowmentchildonfurtherfertility.Inthissample,thebirthofafirst-borngiftedchildincreasesthelikelihoodofathirdbirthby8.5percentagepointsagainstacounterfactualof40percent.Thiseffect,whichdoesnotvarybythegenderofthegiftedchild,impliesa22percenteffectsize.Againstthisquasi-experimentalevidence,theOLSregressionbasedonthewholepopulationshowsastatisticallysignificantnegativerelationshipbetweenthebirthofagiftedchildandthefamilydemandforchildren.

Ontheotherhand,thebirthofalow-endowmentchild,measuredastheenrol-mentofacognitivelydeprivedstudentinaspecialeducationclass,negativelyaffectsfamilysize.However,thiseffectexistsonlyinthesecondexperiment,estimatingtheeffectofasecond-bornlow-endowmentchild.Thisresultisconsistentwithfamilies’preferencesforachildwith“regularendowment”,whichoffsetsalow-endowmentchild’snegativeincomeandpriceeffects.Thebirthofachallengedchildinsecond

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birthreducesthelikelihoodofafourthchildbysevenpercentagepoints,implyinganeffectsizeof18percent.Incontrast,theregressionbasedonthewholepopulationshowsasmallandinsignificantrelationshipbetweenthebirthofachallengedchildandthefamilydemandforchildren.

Ourfindingsrelatetothreestrandsoftheliterature.First,wecontributetothegrowingliteratureontheeconomicsoffertility(seeDoepkeetal.,2022).Thislitera-turehasadvancedseveraltheoriesexplainingfertilitychoiceanditsconsequencesatthemicroandmacrolevels.Ithasalsoaimedtoaccommodatehistoricalandcross-sectionalfertilitytrends,includingtheglobalfertilitydeclineinthepastfewdecades(Jones,2022).Moretraditionaltheoriesexplainfertilitychoiceasdeterminedbyparents’preferencesregardingthetrade-offbetweenquantityandqualityofchildrenandtheopportunitycostofwomen’stime.Recentstudiespointtothecompatibilityofhavingacareerandafamilyasanimportantfactoraffectingfertility.Thecurrentstudyhighlightschildintellectualendowmentasanimportantdeterminantaffectingparents’decisionsoveradditionalchildren.

Morespecifically,ourworkcontributestotheliteratureonthequantity-qualitymodeloffertilityanditsempiricaltesting.ThemaininsightsofthemodelappearinBecker(1960),anditwasfurtherdevelopedandformulatedbyBeckerandothers(primarilyBeckerandLewis1973).MostimportantforthecurrentstudyisBeckerandTomes(1976),whichaddschildqualityendowmenttotheQQmodelandin-vestigatestheoreticallytheeffectsofchangestoitonfertilitychoice.StartingwithBarroandBecker(1989),theQQmodelhasbeenusedtoanalyzefertilitychoiceanditseffectsontheeconomyasawhole,mainlyoneconomicgrowth(seeBeckeretal.,1990).ThesedevelopmentsaidedtheincorporationofQQinunifiedgrowthmodelsthatusethequantity-qualitytrade-offtoexplainthedemographictransition(GalorandWeil,2000;Delventhaletal.,2021;Moav,2005).

AvastliteratureexiststhatempiricallyteststhepredictionsoftheQQmodelusingmicrodata.Muchofthisliteratureestimatestheeffectofashocktothequantityofchildrenonparents’investmentineachchild.Generally,thetrade-offbetweenquantityandqualityofchildrenisfoundmostlyindevelopingcountries(Liu,

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2015;Doepkeetal.,2022).RosenzweigandWolpin(1980),usingthebirthoftwinsasaninstrumentalvariable,findthatanincreaseinchildquantitydecreasededucationinIndia.TherearesimilarresultsforChina(RosenzweigandZhang,2009).Blacketal.(2005)findthattwinbirthhasanegligibleeffectoneducationalattainmentinNorway.However,MogstadandWiswall(2016)arguethatsuchaneffectisnon-linear.Whilethereisasubstitutionbetweenquantityandqualityinlargefamilies,thetwoarecomplementaritiesinsmallfamilies.Juhnetal.(2015,2020)studytheeffectofaquantityshockoncognitiveabilitiesandfindthatbirthspacingplaysanimportantroleindrivingit.UsingthesamedatafromIsraelthatweemployinthisstudy,Angristetal.(2010)foundnoeffectofaquantityshockoneducation,usingbothtwinbirthandthegendercompositionofchildrenasinstrumentalvariables.Inadditiontoexaminingtheimpactofaquantityshock,twostudieshaveestimatedtheeffectofchangesinthepriceofraisingchildrenonfertility.InlinewiththeQQpredictions,Cohenetal.(2013)foundthatareductioninthechildsubsidyinIsraelnegativelyaffectedfertility.BleakleyandLange(2009)findthateradicatinghookwormdiseaseintheUS,whichtheyinterpretasafallinthepriceofquality,causedadeclineinfertility.However,toourknowledge,nostudyhasexaminedtheeffectofaqualityshock–i.e.,theeffectofariseorfallinchildendowment–onfertility.Thus,thepresentstudyaddstotheempiricalliteratureonQQ.

Lastly,ourpapercontributestotheliteratureonparents’responsestotheirchil-dren’snaturalendowment.Studieshaveshownthatparentsadjusttheirbehaviortovariouscharacteristicsoftheirchildren.Forexample,parentsrespondtochildrenwhomanifesthighercognitiveabilitiesearlybyprovidingthemwithincreasedcogni-tivestimulation(Gr¨atzandTorche,2016).Whentwochildrenarebornwithdifferentlevelsofhealthendowment,parentsrespondinanattempttocompensatefortheseinitialdifferencesbyinvestingmoreinthechildwithpoorerhealth(Savelyevetal.,2022).Specifically,AizerandCunha(2012)studytheinteractionbetweenchildhealthendowment,parentalinvestmentinchildren,andfertilityandshowthatpar-entsreinforcedifferencesbetweenchildren’sendowmentsandthatthisreinforcementisstrongerinlargerfamilies.Weshowthatthebirthofachildwithexceptionalin-tellectualendowmentcausesparentstorespondalongtheaxisofdecisionsonfurther

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fertility.

Therestofthepaperisorganizedasfollows.Section2presentstheconceptualframeworkandderivestherelationshipsbetweenchildendowmentanddemandforchildren.Section3characterizesgiftedandchallengedchildren,presentsthedataweuse,ourexplanatoryvariables,andsomedescriptivestatistics.Section4outlinesthequasi-experimentalsettingandtheempiricalstrategy.Section5presentsourestimatesofthechildendowment’seffectonthedemandforchildren,distinguishingbetweenpositive(birthofagiftedchild)andnegative(birthofachallengedchild)shocks.Section6concludes.

2ConceptualFramework

Theprimeeconomicframeworkforanalyzingtheeffectofchildendowmentonfertil-itychoicesisthequantity-quality(QQ)modeloffertility,developedbyBeckerandothers(BeckerandLewis,1973;BeckerandTomes,1976;Becker,1991).TheQQmodelassumesparentsderiveutilityfromthenumberoftheirchildrenandfromthequalityofeachchild.Hence,whendecidingonfertility,parentsbalancebetweentheirdemandforchildrenandtheinvestmentneededtobringeachchildtotheirdesiredlevelofchildquality.Asaresult,changesinthequalityendowmentoftheirchildrenwillaffectparents’fertilitychoices.Thecurrentsectionpresentsanaug-mentationoftheQQmodelinawaythatmakesexplicitthemechanismsunderlyingthiseffectofchildendowment.1Doingsomotivatesourfollowingempiricalanaly-sisandguidesourconceptualizationandinterpretation.WesticktothemodelingframeworkofferedbyBeckertomaintainsimplicity.

Apersoninthemodellivesfortwoperiods:periodt,inwhichsheisachildwithparentswhoinvestinherfutureproductivity,andperiodt+1,inwhichsheisanadultwhoearnsincome,consumes,andmakesdecisionsregardingherownchildren.TheutilityofparentsinperiodtisUt(Zt,nt,It+1),whereZtisparents’consumption,

1BeckerandothershavepresentedseveraldifferentversionsoftheQQmodelacrosstheyears.HerewebuildonthelatestversionpresentedbyBecker(Becker1991),whichwethinkincorporateschildendowmentinthemostdirectway.

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ntisthenumberoftheirchildren,andIt+1isthequalityofeachchild,proxiedbyhisfutureincome.Asstandardintheliterature,weassumediminishingmarginalutilityfromeachofthesegoods.Theincome-generatingfunctionforachildiinperiodtisgivenby

Ii,t+1=(yi,t+ei,t+ui,t+1)wt+1,(1)

whereyi,tistheparents’investmentinthechild,ei,tistheendowedabilityofthechild,andui,t+1isthechild’smarketluck.Thevalueofhumancapitalinperiodt+1isdenotedbywt+1.Importantly,differentchildrenwithinthefamilymayhavedifferentendowments.Specifically,childendowmentei,tiscomposedoftwoelements,

ei,t=ht+?i,t,(2)

wherehtisthequalitybaselineforallchildrenborntothefamilyingenerationt,and?i,tisachild-specificstochasticcomponentwithE[?i,t]=0.Thefamilyendowmentbenchmarkhtcanbethoughtofassomegeneticpotentialabilitysharedbyallchildrenofaspecificcouple,where?i,tisthedeviationofchildi’sactualendowmentfromthatbenchmark.

Weassumeparentsdonotdiscriminatebetweenchildrenandwishtobringthemalltothesamequalitylevel,whichwedenoteIt+1.Parents’budgetconstraintfor

periodtis

n

It=Zt+工yi,t,

i=1

(3)

whereItandyi,taremeasuredinconsumptionunits.AfterplugginginEquation(1)andrearranging,wegetaversionofwhatBeckercallsthe“familyincome”equation,

i=1wt+1,

It+(ei,t+ui,t+1)=Zt+ntIt+1

(4)

wheretheleft-handsiderepresentstheresourcesavailabletothetwo-generationfam-ily,andtheright-handsidethewaytheyareused.Whendecidingonconsumption,fertility,anddesiredlevelofchildquality,parentsmaximizeUt(Zt,nt,It+1)subject

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toEquation(4).However,whenmakingthesedecisions,e.g.,uponmarriage,parentsareuncertainregardingtheendowmentleveloftheirfuturechildren.Specifically,inthecontextofthecurrentpaper,parentsdonotknow,beforegivingbirthtotheirchildren,whatkindofintellectualcapabilitiestheirchildrenwillhave.Hence,theyformanexpectationoftheendowmentleveloftheirchildrenE[ei,t]=E[ht],duetotherandomcomponentofendowmentbeing0inexpectation.Parents’maximizationwithrespecttochildqualityandquantityyieldsthefollowingfirstorderconditions,

=λ[?E[ht]],

(5)

=λ

?Utnt

?It+1wt+1.

(6)

First,notethatthesetwooptimalityconditionsembodytheclassicquantity-qualitytrade-offthatparentsfaceintheQQmodel.Ontheonehand,choosingahigherlevelofqualityforeachchildraisestheshadowpriceofhavingchildren,asinEquation(5).Ontheotherhand,asthenumberofchildrenincreases,bringingeachchildtoahigherlevelofqualitybecomesmoreexpensive,asinEquation(6).

Inaddition,Equation(5)representstherelationshipbetweenparents’demandforchildrenandtheirexpectationoftheendowmentleveloftheirchildren.Asparentsexpecttheirfamily-levelendowmentbenchmarktobehigher,theshadowpriceofchildrendecreases.Alternatively,expectingalowerfamily-levelendowmentinducesparentstoreducetheirdemandforchildren.Theintuitionhereisstraightforward:whenendowmentishigh,parentsneedtoinvestlessresourcestobringtheirchildrentotheirdesiredlevelofquality.Therefore,childrenbecome“cheaper”,thusincreas-ingparents’demandforchildren.Werefertothischannelasthe“priceeffect”ofachangeinendowmentonthedemandforchildren.

Furthermore,weassumeparentsupdatetheirexpectationofthefamily-levelen-dowmentbenchmarkE[ht]witheachchildborn.Thatis,parentsobservetheactu-alizedendowmentofthebornchildanduseitasasignalofthefamily’sht.Asaresult,theyupdatetheirexpectationofthefamily-levelendowmentbenchmarkin

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thedirectionofthesignal.E.g.,supposeachildisbornwithanactualizedendow-mentewhichishigherthanexpected.Hence,parentsupdatetheirexpectationaccordingly,E[ht|e]≥E[ht].However,whileparentsobservethebornchild’sac-tualendowment,theydonotknowwhatcomponentofitshouldbeattributedtothefamily-levelendowmentbenchmarkcommontoalltheirchildrenandwhatisaresultofrandomness.Toillustratethispoint,considerabornchild’sendowmentfromtheperspectiveoftheparents,

e=6tht+(1?6t)ei,t,(7)

where6tistheweightparentsattributetothefamilyendowmentbenchmarkinpro-ducingchildi’srealizedendowmentlevel.Ahigh6tmeansparentsbelievetheactualendowmentofchildiisacleansignaloftheirfamilycommonendowmentlevel.I.e.,futurechildrenwillhaveanendowmentlevelsimilartoi’s.Asaresult,theupdatingofthefamily-levelendowmentbenchmarkinthedirectionofi’sactualendowment,E[ht|e],willbestronger.Incontrast,parentsmaybelievei’sactualendowmentisnotpredicativeoftheendowmentoffuturechildren,asitprimarilyreflectsthechild-specificstochasticcomponent,ei,t.Insuchalow6tcase,theupdatingofE[ht]followingthebirthofiwillbesmaller.

Finally,considertheeffectofgivingbirthtoachildwithanendowmentlevelhigherthanexpected,e>E[ht],i.e.,apositiveendowmentshock.Thepriceeffectisactivatedbecauseparentsupdatetheirexpectationsofthefamily-levelendowmentbenchmark:theshadowpriceofchildrenisreduced,asfuturechildrenareexpectedtobecheaperthanpreviouslythought.Thatraisesparents’demandforadditionalchildrenwithinperiodt.Importantly,themagnitudeofthepriceeffectdependson6t;ahigher6tentailsamoreresponsivedemandwithrespecttoabirthofachildwithunexpectedendowment.Inwords,asparentsbelievetheendowmentoffuturechildrenwillbemoreliketheendowmentoftheiralready-bornchild,theresultingincreaseintheirdemandforadditionalchildrenwillbebigger.Intheextremecaseof6t=0,i.e.,i’sactualendowmentiscompletelyrandom,nopriceeffectexistssincetheshadowpriceoffuturechildrenisunaffectedbyi’sbirth.

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Moreover,thebirthofachildwithanunexpectedendowmentalsoactivatesanincomeeffect.Observethattheresourcesavailabletothefamilyontheleft-handsideofEquation(4)directlyincludetheendowmentofthefamily’schildren.Thus,e.g.,givingbirthtoachildwithanunexpectedlyhighlevelofendowmentraisesparentaldemandforallgoodsinthemodel:consumption,children,andqualityofchildren.Asbefore,becausefewerresourcesareneededtobringthehigh-endowmentchilditothequalityleveldesiredbytheparents,incomeisfreed-up,whichraisesdemandforallnormalgoods.Notethatincontrasttothepriceeffect,theincomeeffectisindependentofthesourceoftheactualendowment,namely,whetheritreflectshtor?i,t.Evenifitiscompletelyrandom,receivingachildwithunexpectedlyhighendowmentincreasesfamilyincomeandthusparents’demandforgoods.

Insum,ourrevisedversionoftheQQmodelpredictsthatgivingbirthtoanunexpectedlyhigh-endowmentchildincreasesdemandforadditionalchildren,andanunexpectedlylow-endowmentchilddecreasesit.Twomechanismsdrivethisef-fect.Thepriceeffectresultsfromparentsupdatingtheirexpectationsofthefamilyendowmentbenchmark,makingfuturechildrencheaper.Secondisanincomeeffect,capturingthechangeinfamilyresourcescausedbythebirthofachildwithanun-expectedendowment,whichthenaffectsparents’demandforallthegoodsinthemodel,includingchildren.

NotethatwechoosenottomodeltheformationofE[ht].Parentsmayexpecttheendowmentoftheirchildrentobesomeaverageoftheirownendowments,thepopulationmean,orsomeotherbenchmarkofcomparison.2Inaddition,wealsodonotmodeltheprocessofupdatingE[ht|e]orofferafunctionalformforit.Wedosoprimarilytomaintaingenerality.Butanyway,sincewecannotobserveE[ht]inourempiricalsetting,modelingitdoesnotcontributetoourempiricalanalysis.ItisworthnotingaswellthatsinceE[ht]isunobserved,wealsocannotdisentangletheroleofthepriceeffectfromthatoftheincomeeffectindrivingourempiricalresults.

Whileourtheoreticalframeworkpointstothepriceandincomeeffectsaswhat

2However,assumingparentsformtheirchildendowmentexpectationbasedontheirownen-dowmentprovidesatheoreticaljustificationforconditioningonparentaleducationwhenestimatingtheeffectofanexceptional-endowmentchild.Wereturntothispointinsection4.

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drivestheimpactofchildendowmentondemandforchildren,wedonotruleouttheexistenceofothermechanismsthatmayexplainthesamepredictions.Forinstance,parentsmaygaindirectutilityfromunexpectedlyhigh-orlow-endowmentchildren,suchthattheeffectontheirdemandforchildrenissimplyduetoatasteeffect.Additionally,parents’utilityfunctionmaychangefollowingtheunexpectedchildendowment.E.g.,parentsmayfindouttheyenjoyhavinganextremelytalentedchildandthereforewantmorechildren,orthathavingachallengedchildishardandthuswantfewerchildren.Achildwithunexpectedendowmentmayalsoaffectmarriagestability,whichinturnwillimpactfuturefertility.TheQQmodeloverlooksthesemechanismsthatmaybedrivingourestimatedeffects.

3BackgroundandData

3.1GiftedandChallengedChildren

Giftedchildrenarechildrenwithexceptionallyhighlevelsofability.Thoughnoclearandagreed-upondefinitionofgiftednessexists,itisuncontroversialthatgiftednessisastableandpersistenttraitindependentofcircumstancesthatchangeacrossone’slife(MonksandKatzko,2005).Itcanmanifestwithinaspecificinterestordomain,e.g.,music,art,mathematics,orasageneralability.Inmosteducationsystems,childrenareidentifiedasbeinggiftediftheyscoreabove130or135onanIQtest.

Childrenwhowerefertoasbeingintellectually“challenged”belongtooneoftwogroups:(1)childrenwithamildintellectualdisabilityor(2)childrenwithse-verelearningdisorders.Thesechildrenstruggletoattaintheabilitytolisten,read,write,conceptualize,orusemath.Whiletheenvironmentsuchachildissituatedinmaycontributetodevelopingtheirabilities,intellectualdisability,andlearningdisordersarepermanentconditions.Likegiftedchildren,childrenareidentifiedasbeingchallengedbytheirIQscore,generallybetween50and70.

Exceptionalintellectualability–highorlow–manifestsitselfearlyinlife,aschildrenshowsignsofrapid,orveryslow,developmentofcognitiveandmotorabil-

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ities(Davis&Rimm2004,Renzulli2002,Silverman2004).Forexample,giftedchildrenlearnnewconceptsveryquicklyandgeneralizethemeasily,exhibitexcel-lentmemory,andgraspthestructureoflanguageanditsusagemuchearlierthantheirpeers(Clark2002,Manning2006).Theyalsoquicklydevelopmotorskillsandcancompletecomplextaskswithrelativelylittleinstruction.

Ontheotherhand,childrenwithintellectualanddevelopmentaldisabilitiesfailtoachievecognitivemilestonesintheirearlyyearsoflife,astheystrugglewithcom-prehendingandprocessinginformation,usinglanguage,andsolvingsimpleproblems(Schalocketal.,2021).Inaddition,whiletheirpeers’behaviorchangeswithage,thebehaviorofchallengedchildrenremainsmorerigid.Theseearlysignscanstartappearingrightafterbirthforbothgiftedandchallengedchildren.

However,theearlydevelopmentalsignalsofexceptionalendowmenttendtobeverynoisyandunreliable.Thiscomplicatestheabilityofparentsandeducationalin-stitutionstorecognizechildren’sexceptionalityduringtheirfirstyearsoflife.Instead,ataroundages4to7,amorepreciseidentificationofachild