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The Wage Impact of the Marielitos: A Reappraisal
George J. Borjas Harvard University
October 2015
1
The Wage Impact of the Marielitos: A Reappraisal
George J. Borjas
ABSTRACT
ThispaperbringsanewperspectivetotheanalysisoftheMarielsupplyshock,revisiting
thequestionandthedataarmedwiththeaccumulatedinsightsfromthevastliteratureon
theeconomicimpactofimmigration.Acruciallessonfromthisliteratureisthatany
credibleattempttomeasurethewageimpactofimmigrationmustcarefullymatchthe
skillsoftheimmigrantswiththoseofthepre-existingworkers.TheMarielitoswere
disproportionatelylow-skill;atleast60percentwerehighschooldropouts.Areappraisal
oftheMarielevidence,specificallyexaminingtheevolutionofwagesinthelow-skillgroup
mostlikelytobeaffected,quicklyoverturnsthefindingthatMarieldidnotaffectMiami’s
wagestructure.TheabsolutewageofhighschooldropoutsinMiamidroppeddramatically,
asdidthewageofhighschooldropoutsrelativetothatofeitherhighschoolgraduatesor
collegegraduates.ThedropintherelativewageoftheleasteducatedMiamianswas
substantial(10to30percent),implyinganelasticityofwageswithrespecttothenumber
ofworkersbetween-0.5and-1.5.Theanalysisalsodocumentsthesensitivityofthe
estimatedwageimpacttothechoiceofaplacebo.Themeasuredimpactismuchsmaller
whentheplaceboconsistsofcitieswherepre-Marielemploymentgrowthwasweak
relativetoMiami.
2
The Wage Impact of the Marielitos: A Reappraisal
George J. Borjas* I. Introduction
Thestudyofhowimmigrationaffectslabormarketconditionshasbeenacentral
concerninlaboreconomicsfornearlythreedecades.Thesignificanceofthequestionarises
notonlybecauseofthepolicyissuesinvolved,butalsobecausethestudyofhowlabor
marketsrespondtosupplyshockscanteachusmuchabouthowlabormarketswork.Inan
importantsense,examininghowimmigrationaffectsthewagestructureconfrontsdirectly
oneofthefundamentalquestionsineconomics:Whatmakespricesgoupanddown?
DavidCard’s(1990)classicstudyofthelabormarketimpactoftheMarielsupply
shockstandsasalandmarkinthisliterature.OnApril20,1980,FidelCastrodeclaredthat
CubannationalswishingtomovetotheUnitedStatescouldleavefreelyfromtheportof
Mariel,andaround125,000Cubansquicklyacceptedtheoffer.TheCardstudywasoneof
thepioneeringattemptstoexploittheinsightthatacarefulstudyofnaturalexperiments,
suchastheexogenoussupplyshockstimulatedbyCastro’sseeminglyrandomdecisionto
“letthepeoplego,”canhelpidentifyparametersofsignificanteconomicinterest.In
particular,theMarielsupplyshockwouldletusmeasurethewageelasticitythatshows
howthewageofnativeworkersrespondstoanexogenousincreaseinsupply.
Card’sempiricalanalysisoftheMiamilabormarket,whencomparedtoconditions
inotherlabormarketsthatservedasacontrolgroupor“placebo,”indicatedthatnothing
muchhappenedtoMiamidespitetheverylargenumberofMarielitos.Nativewagesdidnot
godownintheshortrunaswouldhavebeenpredictedbythetextbookmodelofa
competitivelabormarket.Andunemployment,evenforgroupswithlowaverageskills,
remainedunchangedrelativetowhatwashappeningintheplacebocities.Card’sstudyhas
*HarvardUniversity,NationalBureauofEconomicResearch,andIZA.Iamparticularlygratefulto
AlbertoAbadieandLarryKatzforveryproductivediscussionsoftheissuesexaminedinthispaperandformanyvaluablecommentsandsuggestions.IhavealsobenefittedfromthereactionsandadviceofJoshAngrist,FranBlau,BrianCadena,KirkDoran,RichardFreeman,DanielHamermesh,GordonHanson,AlanKrueger,JoanLlull,JoanMonras,PanuPoutvaara,MartaTienda,andSteveTrejo.Ialoneamresponsibleforallerrors.
3
beenextremelyinfluential,bothintermsofitsprominentroleinpolicydiscussionsandits
methodologicalapproach.1
Duringthe1980sand1990s,aparallel(butnon-experimental)literatureattempted
toestimatethelabormarketimpactofimmigrationbyessentiallycorrelatingwagesand
immigrationacrosscities(Grossman,1982;Borjas,1987;AltonjiandCard,1991).These
spatialcorrelationshavebeencriticizedfortworeasons:(1)immigrantsaremorelikelyto
settleinhigh-wagecities,sothattheendogeneityofsupplyshocksinducesaspurious
positivecorrelationbetweenimmigrationandwages;and(2)nativeworkersandfirms
respondtosupplyshocksbyresettlinginareasthatofferbetteropportunities,effectively
diffusingtheimpactofimmigrationacrossthenationallabormarket.
Card’sMarielstudyisimpervioustobothofthesecriticisms.Thefactthatthe
MarielitossettledinMiamihadlittletodowithpre-existingwageopportunities,andmuch
todowiththefactthatCastrosuddenlydecidedtoallowtheboatlifttooccurandthatthe
Cuban-AmericanswhoorganizedtheflotillalivedinSouthFlorida.2Similarly,thevery
shortrunnatureofCard’sempiricalexercise,effectivelylookingattheimpactof
immigrationjustafewyearsafterthesupplyshock,meansthatweshouldbemeasuring
theshort-runelasticity,anelasticitythatisnotyetcontaminatedbylabormarket
adjustmentsandthateconomictheorypredictstobenegative.
AngristandKrueger’s(1999)analysisofthe“TheMarielBoatliftThatDidNot
Happen”providesthemostimportantconceptualcriticismofCard’sstudytodate:3
Inthesummerof1994,tensofthousandsofCubansboardedboatsdestinedforMiamiinanattempttoemigratetotheUnitedStatesinasecondMarielBoatliftthatpromisedtobealmostaslargeasthefirstone...Wishingtoavoidthepoliticalfalloutthataccompaniedtheearlierboatlift,theClintonAdministrationintercededandorderedtheNavytodivertthewould-be
1StudiesthatexamineexogenoussupplyshocksthatareclearlyinfluencedbytheCardanalysis
includeHunt(1992),CarringtonanddeLima(1996),Friedberg(2001),Saiz(2003),BorjasandDoran(2012),Glitz(2012),Pinottietal(2013),andDustmann,Schönberg,andStuhler(2015).
2Boththe1990and2000censusesreportthatalmosttwo-thirdsoftheCubanimmigrantswholikelywerepartoftheMarielinfluxstillresidedintheMiamimetropolitanarea.
3Therehavealsobeenmanydiscussionsofthestatisticalinferencedifficultiesraisedbythistypeofanalysis;seeBertrand,Duflo,andMullainathan(2004),DonaldandLang(2007),andAydemirandKırdar(2013).
4
immigrantstoabaseinGuantanamoBay.OnlyasmallfractionoftheCubanémigréseverreachedtheshoresofMiami.Hence,wecallthisevent,"TheMarielBoatliftThatDidNotHappen"(AngristandKrueger,1999,p.1328;emphasisadded).
AngristandKruegerreproducedthemethodologicaldesignofCard’sMarielarticle
bycomparingthelabormarketinMiamibeforeandafter1994withthesamesetofplacebo
cities.Itturnedoutthatthispotentialsupplyshockmadethingsmuchworseforsome
natives.Forexample,theblackunemploymentrateinMiamiincreasedfrom10to14
percent,atatimethattheaggregateeconomywasboomingandunemploymentwas
droppingintheplacebocities.
Theusualinterpretationwouldhavetobethata“phantommenace”ofnon-existent
workersharmedMiami’sAfrican-Americanworkforce.Itobviouslymakesnosenseto
makesuchaclaim,butthisraisesanimportantquestion:Doestheevidencefromthe
Marielboatliftthatdidhappenreallyindicatethatimmigrationhadnoimpact?AsAngrist
andKrueger(1999,p.1329)conclude,“Sincetherewasnoimmigrationshockin1994,this
illustratesthatdifferentlabormarkettrendscangeneratespuriousfindingsinresearchof
thistype.”
Inretrospect,however,theAngrist-Kruegerclaimthat“onlyasmallfractionofthe
CubanémigréseverreachedtheshoresofMiami,”writtenbeforetheavailabilityofthe
2000census,wasnotaccurate.AsIwillshowshortly,PresidentClinton’sdecisionto
reroutethepotentialmigrantstoGuantanamoseemedtoonlydelayasizablesupplyshock
ofaround50,000Cubansbyonlyayearorso.Asaresult,itmaybedifficulttoinfermuch
fromthecomparisonoftheMarielsupplyshocktothe1994eventthatendedupbringing
manyimmigrantstotheMiamimetropolitanarea.
ThispaperprovidesareappraisaloftheevidenceofhowtheMiamilabormarket
respondedtotheinfluxofMarielitos.Thepaperisnotareplicationoftheearlierstudies.
Instead,Iapproachandexaminethesequestionsfromafreshperspective,buildingonwhat
wehavelearnedfromthe30yearsofresearchonthelabormarketimpactofimmigration.
Onecrucialinsightfromthisresearchisthatanycredibleattempttomeasuretheimpact
mustcarefullymatchtheskillsoftheimmigrantswiththeskillsofthepre-existing
workforce.Borjas(2003),inthestudythatintroducedtheapproachofcorrelatingwages
5
andimmigrationacrossskillgroupsinthenationallabormarket,foundasignificant
negativecorrelationbetweenthewagegrowthofspecificskillgroups,definedbyeducation
andage,andthesizeoftheimmigration-inducedsupplyshockintothosegroups.
Theanalysisoftheavailablemicrodatausingthisnewperspectiveprovidesavery
differentpictureofwhathappenedafterMariel.Asiswellknown,theMarielitoswere
disproportionatelylow-skill;around60percentwerehighschooldropoutsandonly10
percentwerecollegegraduates.Atthetime,aboutaquarterofMiami’spre-existing
workerslackedahighschooldiploma.Asaresult,eventhoughtheMarielsupplyshock
increasedthenumberofworkersinMiamiby8percent,itincreasedthenumberofhigh
schooldropoutsbyalmost20percent.
Theunbalancednatureofthissupplyshockobviouslysuggeststhatweshouldlook
atwhathappenedtothewageofhighschooldropoutsinMiamibeforeandafterMariel.
Remarkably,thistrivialcomparisonwasnotmadeinCard’s(1990)studyand,tothebestof
myknowledge,hasnotyetbeenconducted.4Byfocusingonthisveryspecificskillgroup,
thefindingthattheMarielsupplyshockdidnothaveanyconsequencesforpre-existing
workersimmediatelydisappears.Infact,theabsolutewageofhighschooldropoutsin
Miamidroppeddramatically,asdidthewageofhighschooldropoutsrelativetothatof
eitherhighschoolgraduatesorcollegegraduates.Thedropinthelow-skillwagebetween
1979and1985wassubstantial,perhapsasmuchas30percent.
Theevidencereportedinthispaperprovidesanentirelynewperspectiveofhow
theMiamilabormarketrespondedtoanexogenoussupplyshock.Atleastintheshortrun,
thelabormarketrespondedpreciselyinthewaythatthe“textbook”modelpredicts:an
increaseinthenumberofpotentialworkersloweredthewageofthoseworkerswhofaced
themostcompetitionfromthenewimmigrants.Itseemsthattheshort-runlabordemand
curve,evenintheMiamioftheearly1980s,wasdownwardslopingafterall.
4Table7inCard(1980)reportswageandemploymentchangesforthesubsampleofblackhigh
schooldropouts,butdoesnotreportanyotherpre-postMarieldifferencesfortheleasteducatedworkers.Card’sfindingthattheblackwageinMiamideclinedafterMariel,whichheattributestocyclicalfluctuations,willbediscussedbelow.Inanunpublishedonlineappendix,Monras(2014)attemptstoreplicatesomeofCard’sresultsandalsoexamineswagetrendsinthesampleofworkerswhohaveatmostahighschooldiploma.Monras’sevidenceisverysuggestiveofthefindingsreportedinthispaper.
6
II. Data ThemigrationoflargenumbersofCubanstotheUnitedStatesbeganshortlyafter
FidelCastro’scommunisttakeoveronJanuary1,1959.Bytheyear2010,over1.3million
Cubanshademigrated.
Thefirstlarge-scaledatasetthatpreciselyidentifiesanimmigrant’syearofarrival
isthe2000decennialcensus.Priorto2000,thecensusmicrodatareportedtheyearof
arrivalinintervals(e.g.,1960-1964).Imergedthedatafromvariouscensusesandthe
AmericanCommunitySurveys(ACS)toconstructamortality-adjustednumberofCuban
immigrantsforeacharrivalyearbetween1955and2010.5Forexample,Iusedthe1970
censustoestimatethenumberofCubanimmigrantswhoarrivedintheUnitedStates
between1960and1964,andthenusedthedetailedyear-of-migrationinformationinthe
2000censustoallocatethoseearlyimmigrantstospecificyearswithinthe5-yearband.
Figure1showsthetrendinthenumberofCubansmigratingtotheUnitedStates.
Severalpatternsemergefromthetimeseries.First,itiseasytoseetheimmediate
impactofthecommunisttakeoveroftheisland.In1958,only8,000Cubansmigratedtothe
UnitedStates.By1961and1962,52,000Cubansweremigratingannually.6TheCuban
MissileCrisisabruptlystoppedthisflowinOctober1962,andittookseveralyearsfor
otherescaperoutestoopenup.Bythelate1960s,thenumberofCubansmovingtothe
UnitedStateswasagainnearthelevelreachedbeforetheMissileCrisis.
Thehugespikein1980,ofcourse,istheMarielsupplyshock.Between1978and
1980,thenumberofnewCubanimmigrantsincreased17-fold,from6,500to110,000.The
figureshowsyetanotherspikein1994and1995,coincidingwiththeperiodofAngristand
Krueger’s(1999)“MarielBoatliftThatDidNotHappen.”Thecensusdataclearlyindicates
thatsomehowthe“phantom”CubansfromthatboatliftendedupintheUnitedStates,
makingthissupplyshockaLittleMariel.Althoughthenumberof“LittleMarielitos”palesin
comparisontothenumberofactualMarielitos,itisstillquitelarge;thenumberofmigrants
arrivingin1995wassimilartothatoftheearlyCubanwavesinthe1960s.Itisalsoevident
5Inprinciple,thecalculationalsoadjustsforpotentialout-migrationofCubanimmigrants.Isuspect,
however,thatthenumberofCubanswhochosetoreturnistriviallysmall(althoughalargernumbermighthavemigratedelsewhere).
6Fulldisclosure:Iamadatapointinthe1962flow.
7
thattherehasbeenasteadyincreaseinthenumberofCubanmigrantssincetheearly
1980s.By2010,about40,000Cubanswerearrivingannually.
OnelastdetailisworthnotingabouttheCubanmigration:Adisproportionately
largenumberoftheimmigrantsendedupresidingintheMiamimetropolitanarea.The
fractionofCubanimmigrantsresidinginMiamiwas50percentinthe1980census,58
percentinthe1990census,and60percentinthe2000census.RegardingtheMarielitos
themselves,62.6percentoftheMarielitosresidedinMiamiin1990and63.4percentstill
residedtherein2000.
Themaindatasetsusedintheempiricalanalysisarethe1977-1993March
SupplementsoftheCurrentPopulationSurveys(CPS).7Thesesurveysreporttheannual
wageandsalaryincomeaswellasthenumberofweeksworkedbyarespondentinthe
previouscalendaryear.Thewageanalysiswillberestrictedtomenaged25-59,whoare
notself-employed,whoarenotenrolledinschool,andwhoreportpositiveannualearnings,
positiveweeksworked,andpositiveusualhoursworked.8Theagerestrictionensuresthat
aworker’sobservedearningsarenotcontaminatedbytransitoryfluctuationsthatoccur
duringthetransitionsfromschooltoworkandfromworktoretirement.
The1977-1993periodthatwillbeanalyzedthroughoutmuchofthepaperis
selectedfortworeasons.First,althoughtheMarchCPSdatafilesareavailablesince1962,
theMiamimetropolitanareacanonlybeconsistentlyidentifiedinthe1973-2004surveys.
Beginningwiththe1977survey,theCPSbegantoidentify44metropolitanareas(including
Miami)thatcanbeusedintheempiricalanalysis.9Second,myanalysisofwagetrendswill
7TheMarchsurveysareknownastheAnnualSocialandEconomicSupplements(ASEC).Thedata
wasdownloadedfromtheIntegratedPublicUseMicrodataSeries(IPUMS)websiteonAugust22,2015.Card(1990)usedtheCPSOutgoingRotationGroups(ORG).IwillshowbelowthattheevidencefromtheORGdataleadstoasimilarinference:somethingdidindeedhappentothelow-skilllabormarketinpost-MarielMiami.
8Inaddition,Iexcludepersonswhoresideingroupquartersorhaveanegativesampleweight.Itistemptingtoincreasesamplesizebyincludingworkingwomeninthestudy,butfemalelaborforceparticipationwasincreasingveryrapidlyinthe1980s,sothatwagetrendsarelikelytobeaffectedbytheselectionthatmarkswomen’sentryintothelabormarket.Thelaborforceparticipationrateofwomen(aged18-64)increasedfrom52.1to72.5percentbetween1980and1990inMiami,andfrom49.2to71.2percentinallotherurbanareas.
9TheMiami-Hialeahmetropolitanareaisnotidentifiedatallbefore1973,andiscombinedwiththeFortLauderdalemetropolitanareaafter2004.The1973-1976surveysidentifyonly34metropolitanareas,andoneofthem(NewYorkCity)isnotconsistentlydefinedthroughouttheperiod;theNassau-SuffolkmetropolitanareaispooledwiththeNewYorkCitymetroareain1976.
8
stopwiththe1993surveytoavoidcontaminationfromtheLittleMarielsupplyshockof
1994and1995.
TheCPSdidnotreportaperson’scountryofbirthbefore1994,sothatitisnot
possibletomeasurethewageimpactoftheMarielsupplyshockonthenative-born
population.Iinsteadexaminetheimpactonnon-Hispanicmen(whereHispanic
backgroundisdeterminedbyaperson’sanswertotheHispanicethnicityquestion),a
samplerestrictionthatcomesclosetoidentifyingMiami’snative-bornpopulationatthe
time.Forexample,the1980census,conducteddaysbeforetheMarielsupplyshock,
reportsthat40.7percentofMiami’smaleworkforcewasforeign-born,with65.1percentof
theimmigrantsborninCubaandanother11.2percentborninotherLatinAmerican
countries.
Thelabormarketoutcomeexaminedthroughoutthestudywillbetheworker’slog
weeklyearnings,whereweeklyearningsaredefinedbytheratioofannualincomeinthe
previouscalendaryeartothenumberofweeksworked.IusetheConsumerPriceIndex
(CPI)forallurbanconsumerstodeflatetheearningsdata(1980=100).10Forexpositional
consistencyandunlessotherwisenoted,wheneverIrefertoaparticularcalendaryear
hereafter,itwillbetheyearinwhichearningswereactuallyreceivedbyaworker,as
opposedtotheCPSsurveyyear.11
Beforeproceedingtoanexaminationofwagetrends,itisimportanttodocument
whatweknowabouttheskilldistributionoftheMarielitos.Asnotedearlier,theMariel
supplyshockbeganafewdaysafterthe1980censusenumeration,sothatthefirstlarge
surveythatcontainsalargesampleoftheMarielitosthemselvesisthe1990census.
Nevertheless,afewCPSsupplementsconductedinthe1980s(includingApril1983,June
1986,andJune1988)provideinformationona(very)smallsampleofCubanimmigrants
whoarrivedatthetimeofMariel.
10Tominimizetheproblemofoutlyingobservations,Iexcludeallworkerswhoearnlessthan$1.50
anhourormorethan$40anhour(in1980dollars).Thisrestrictionapproximatelydropsworkersinthetopandbottom1percentoftheearningsdistribution.Ireplicatedtheanalysisusingtheloghourlywageasanalternativemeasureofaworker’sincome,andtheresultsaresimilartothosereportedinthispaper.
11Forexample,adiscussionoftheearningsofworkersin1985referstothedatadrawnfromthe1986MarchCPS.
9
Table1presentstheeducationdistributionofthesampleofadultCubanimmigrants
whoarrivedin1980(orin1980-1981,dependingonthedataset)andwhowere
enumeratedinvarioussurveyssometimebetween1983and2000.Thecalculationincludes
theentirepopulationofMarielitos(workersandnon-workers,aswellasmenandwomen)
whowereatleast18yearsoldasof1980.
ThecrucialimplicationofthetableisthattheMarielsupplyshockconsistedof
workerswhowereveryunskilled,witharemarkablylargefractionoftheMarielitosbeing
highschooldropouts.12Despitethevariationinsamplesizeandthealmost20-yearspanin
thesurveysreportedinthetable,thefractionofMarielitoswholackedahighschool
diplomahoversaround60percent.Table1alsoshowsthataverysmallfractionofthese
immigrantswerecollegegraduates(around10percent).
ItisinsightfultocomparetheeducationdistributionoftheMarielitoswiththatof
thepre-existingworkforce.ThelastrowofTable1showsthat“only”26.7percentoflabor
forceparticipantsintheMiamimetropolitanareawerehighschooldropouts.Infact,
Miami’sworkforcewasremarkablybalancedintermsofitsskilldistribution,with20to30
percentofworkersineachofthefoureducationgroups.13
Table2summarizeswhatweknowaboutthemagnitudeoftheMarielsupplyshock.
Therewere176,300highschooldropoutsinMiami’slaborforcejustpriortoMariel(outof
atotalof659,400).Accordingtothe1990census,60,100Cubanworkersmigrated(as
adults)eitherin1980or1981.Ifwemakeaslightadjustmentforthesmallnumberwho
enteredthecountryin1981,Marielincreasedthesizeofthelaborforceby55,700persons,
ofwhichalmost60percentwerehighschooldropouts.14AlthoughtheMarielsupplyshock
12ThefactthatmostoftheadultMarielitoslackedahighschooldiplomadoesnotnecessarilyimply
thattheydidnotcompletecompulsoryschoolinginCuba.ThereisalsoapossibilitythattheskillsoftheMarielitoswerefurther“downgraded”uponarrival,asinDustmann,Frattini,andPreston(2013),sothateventhoseimmigrantswithahighschooldiplomawerestillcompetingwiththeleasteducatedworkersinthepre-existingMiamiworkforce.
13Thepre-existingworkforceincludesalllaborforceparticipantsinMiami,regardlessofwheretheywerebornortheirethnicity.Thefractionofnon-Hispanicworkerswhowerehighschooldropoutswasalsoveryhigh(19.8percent).
14The2000censusindicatesthatapproximately92.8percentoftheCubanimmigrantswhoenteredthecountryineither1980or1981actuallyenteredin1980.ItisalsoimportanttonotethatthesupplyshockwasprobablyslightlylargerthanindicatedinTable2becausethecalculationdoesnotaccountformortalitythrough1990.
10
increasedMiami’sworkforceby8.4percentandincreasedthenumberofthemost
educatedworkersby3to5percent,thesizeofthelow-skilllaborforcerosebya
remarkable18percent.Moreover,thissupplyshockoccurredalmostovernight(Stabile
andScheina,2015).ThefirstMarielitosarrivedinFloridaonApril23,1980.TheCoast
Guardreportsthatover100,000refugeeshadreachedtheFloridashoresbyJune3.
III. Descriptive Evidence TheverylowskillsoftheMarielitosindicatesthatweshouldperhapsfocusour
attentiononthelabormarketoutcomesoftheleasteducatedworkersinMiamitogeta
first-ordersenseofwhetherthesupplyshockhadanyimpactonMiami’swagestructure.In
fact,theliteraturesparkedbyBorjas(2003)suggeststhatitisimportantto“match”the
immigrantstocorrespondingnativeworkersbyskillgroups.Educationalattainmentisa
skillcategorythatwouldseemtobeextremelyrelevantinanexaminationoftheMariel
supplyshock.
AnyempiricalstudyoftheimpactofMarielencountersanimmediatedataproblem:
ThenumberofworkersenumeratedbytheCPSintheMiamilabormarketissmall,
introducingalotofrandomnoiseintoanycalculation.Inparticular,thenumberofnon-
HispanicmenwhosatisfythesamplerestrictionsandwhoareemployedintheMiamiarea
wasaround90-100perCPScross-sectioninthe1980s,withaboutaquarterconsistingof
highschooldropouts.Thesamplesizeproblem,however,becomesparticularlyacutewith
the1991survey,whenthenumberofnon-HispanicmensampledinMiamifallsabruptly
(byalmostathird),andthenumberofhighschooldropoutsdropstothesingledigits.This
changeinsamplesizesuggeststhattheevidenceisprobablymostcrediblewhenwe
examineoutcomesduringthefirstdecadeafterMariel.
Nevertheless,itisinstructivetostartbyreportingtheevidencefromthemost
straightforwardcalculationofthepotentialwageimpactthatusesalltheavailabledata.It
turnsoutthateventhemostcursoryexaminationofthewagetrendsrevealsaremarkable
patternthatimmediatelyoverturnstheconventionalwisdomaboutMariel:Something
indeeddidhappentothewagestructureinMiamiafter1980.Itseems,infact,asifthe
11
Marielitosmayhavehadalargeandadversewageimpactonthewageofcomparable
Miamiansafterall.
Toeasilyillustratethekeyfindingofthispaper,Isimplycalculatetheaveragelog
weeklywageofhighschooldropoutsinMiamieachyearbetween1972and2003,the
periodforwhichtheMarchCPShasaconsistenttimeseriesfortheMiamimetropolitan
area.Figure2illustratesthewagetrend,usinga3-yearmovingaveragetosmoothoutthe
noiseinthetimeseries.Thefigurealsoillustratesthetrendforsimilarlyeducatednon-
HispanicmenworkingoutsideMiami.Itisimportanttoemphasizethatthissimpleexercise
doesnotadjusttheCPSdatainanywaywhatsoever(otherthantakingamovingaverage),
sothatitprovidesaverytransparentindicationofwhathappenedtowagesinMiamipre-
andpost-Mariel.
ItisobviousthatdespitethesimilarityinwagetrendsbetweenMiamiandtherest
oftheUnitedStatespriorto1980,somethinghappenedin1980thatcausedthetwowage
seriestodiverge.BeforeMariel,thelogwageofhighschooldropoutsinMiamiwas0.10log
pointsbelowthatofworkersintherestofthecountry.By1985,thegaphadwidenedto
0.42logpoints,implyingthatwhatevercausedthedivergencehadloweredtherelative
wageoflow-skillworkersinMiamibyaround30percent.Notethatthelow-skillwagein
Miamifullyrecoveredby1990,onlytobe“hammered”againin1995,coincidentallythe
timeoftheLittleMarielsupplyshock.By2002,thewagegapbetweenhighschooldropouts
inMiamiandelsewherehadreturnedtoitspre-Marielnormalofaround0.11logpoints.
Ofcourse,thedistinctivewagetrendinMiamimaynotappearquiteasdistinctive
whencontrastedwithwhathappenedinotherspecificcities.ThecomparisonofMiamito
anaggregateoftheU.S.labormarketmaybemaskingalotofthevariationthatinfluences
particularplacesandthatdisappearswhenaveragedout.Itis,therefore,importantto
createacontrolgroupofcomparablecitiesunaffectedbytheMarielsupplyshockto
determineifthewagetrendsevidentinMiamiwereduetomacroeconomicfactorsthat
affectedothersimilarcommunitiesaswell.Beginningwiththe1977survey,theMarchCPS
dataidentifies43metropolitanareasthatcanbecombinedinsomefashiontoconstructa
sortofplacebo.Card(1980,p.249;emphasisadded)describestheconstructionofhis
controlgroupasfollows:
12
Forcomparativepurposes,Ihaveassembledsimilardata…infourothercities:Atlanta,LosAngeles,Houston,andTampa-St.Petersburg.ThesefourcitieswereselectedbothbecausetheyhadrelativelylargepopulationsofblacksandHispanicsandbecausetheyexhibitedapatternofeconomicgrowthsimilartothatinMiamioverthelate1970sandearly1980s.Acomparisonofemploymentgrowthrates…suggeststhateconomicconditionswereverysimilarinMiamiandtheaverageofthefourcomparisoncitiesbetween1976and1984.
ItisimportanttoemphasizethatthefourcitiesintheCardplacebowerechosen
partlybasedonemploymenttrendsobservedaftertheMarielsupplyshock.Putdifferently,
ifMarielworsenedemploymentconditionsinMiami,theCardplaceboiscomparingthe
pooreroutcomesofworkersinMiamitotheoutcomesofworkersincitieswheresome
otherfactorworsenedtheiropportunitiesaswell.Itisobviouslyfarpreferableto
exogenizethechoiceofaplacebobycomparingcitiesthatwereroughlysimilarpriortothe
treatment,ratherthanbeingsimilarafteroneofthemwas“injected”withaverylarge
supplyshock.
ThevariouspanelsofFigure3illustratethewagetrendsinMiamiandseveral
potentialplacebosbetween1976and1992.Thetoppanelshowsthatthelogwageofhigh
schooldropoutsdeclineddramaticallyafter1980whencomparedtowhathappenedinthe
citiesthatmakeuptheCardplacebo.Ofcourse,trendsinabsolutewagesreflectmany
factorsthatarespecifictolocallabormarkets,sothatitispossiblethattheseupsand
downscaptureidiosyncraticshiftsthataffectedallworkersinMiami.TheMarielsupply
shock,however,specificallytargetedtheleasteducatedworkersandthebottomtwo
panelsofthefigureshowthattherelativewageofhighschooldropoutsinMiami—relative
toeithercollegegraduatesorhighschoolgraduates—alsodeclineddramaticallyafter
Mariel,andalsorecoveredby1990.15Insum,thewagetrendsobservedinMiami—relative
tothoseseeninthecitiesthatmakeuptheCardplacebo—consistentlyindicatethatthe
15ThetimeseriesofthewageofhighschooldropoutsinMiamirelativetohighschoolgraduateshas
adataquirkthatisworthnoting:HighschooldropoutsearnedslightlymorethanhighschoolgraduatespriortoMariel.ThisanomalyarisesbecausetheaveragewageofhighschoolgraduatessampledbytheCPSinMiamiin1979isunusuallylow,andthisdataanomalycarriesovertoneighboringyearsbecauseofthemovingaveragecalculation.Allthefindingsinthispaperareinvarianttodroppingthe1979observation.Thefigurealsoshowsthatthewageofhighschooldropoutsagainexceedsthatofhighschoolgraduatesafter1990.Asnotedearlier,however,thereisaprecipitousdropinthenumberofhighschooldropoutssampledinMiamiafter1990.
13
economicwell-beingoftheleasteducatedworkersinMiamitookadownwardturnshortly
after1980,reacheditsnadiraround1985-1986,anddidnotrecoverfullyuntil1990.
Asnotedabove,thecitiesintheCardplacebodonotmakeupapropercontrol
groupbecausetheywerechosen,inpart,sothatpost-Marielemploymentconditionsinthe
placebocitiesresembledthoseinMiami.Todeterminethesetofcitiesthathadcomparable
employmentgrowthpriortoMariel,Ipooledthe1977and1978cross-sectionsoftheCPS,
andalsopooledthe1979and1980cross-sections.16Notethatthe1980CPSdata,collected
inMarch,isnotaffectedbythesupplyshock,astheMarielitosdidnotbegintoarriveuntil
lateApril.Ithenusedthetwopooledcross-sectionstocalculatethelogoftheratioofthe
totalnumberofworkersin1979-1980tothenumberofworkersin1977-1978.Column1
ofTable3reportstheemploymentgrowthrateforeachofthe44metropolitanareas,
rankedbythegrowthrate.
ItisevidentthatMiami’spre-Marielemploymentconditionswerequiterobust,
ranking6thintherateofemploymentgrowth.NotethatallthecitiesthatmakeuptheCard
placebohadlowergrowthratesthanMiamibetween1977and1980.Infact,theaverage
employmentgrowthrateinthosefourcities(weightedbyaverageemployment)was6.9
percent,lessthanhalfthe15.3percentgrowthrateinMiami.
IusetherankingsreportedinTable3toconstructanewplacebo,whichIcallthe
“employmentplacebo,”bysimplychoosingthefourcitiesthatweremostsimilartoMiami
priorto1980.Specifically,theemploymentplaceboconsistsofthefourcities(Anaheim,
Rochester,Nassau-Suffolk,andSanJose)rankedjustaboveandjustbelowMiami.
Figure3clearlyshowsthattherelativedeclineinthewageoflow-educatedworkers
inMiamiismuchlargerwhenwecompareMiamitocitiesthathadcomparable
employmentgrowththantothecitiesthatmakeuptheCardplacebo.Between1979and
1985,forinstance,thewageofhighschooldropoutsinMiamirelativetotheCardplacebo
fellbyabout0.28logpoints(or24percent),butthedeclinewasabout0.48logpoints(38
percent)whencomparedtothecitiesintheemploymentplacebo.Thisdifference,ofcourse,
isnotsurprising.Thecomparisonofpost-MarieleconomicconditionsinMiamitothatof
16Theseyearsrefertothesurveyyearsandnotthecalendaryearswhereearningsareobserved.A
personisemployedifheorsheworksintheCPSreferenceweek.
14
citieswhereemploymentconditionsarealsopoorbyconstructioninevitablyhidessomeof
theimpactoftheMarielitos.
Inshort,thechoiceofaplaceboplaysacrucialroleindeterminingthewageimpact
ofMariel.Thefactthatthereare43metropolitanareasfromwhichtoselecta4-citycontrol
group(anumberthatisitselfarbitrary)impliesthatthereareatotalof123,410potential
placebos.Inviewoftheverylargenumberofchoices,itmightbereasonabletoexpecta
hugedispersionintheestimatedwageeffectoftheMarielitosacrossthe123,410potential
comparisonsthatcanbemade.Iwillreportbelowthedistributionofestimatedwage
impactsacrossallpotentialfour-cityplacebosandshowthatthewageimpactofMarielis
significantlylargerwhentheplacebocontainscitiesthatbetterresembledMiami’s
economicconditionsbefore1980.
Analternativewayofchoosingaplaceboistoemploythe“syntheticcontrol”
statisticalmethoddevelopedbyAbadie,Diamond,andHainmueller(2010).Themethod
essentially“searches”acrossallpotentialplacebocitiesandderivesaweightthataverages
citiestocreateanewsyntheticcity.Thissyntheticcityistheonethatbestresemblesthe
pre-MarielMiamilabormarket.Thesyntheticcontrolapproachhastwobeneficial
properties.First,itprecludestheresearcherfrommakingarbitrarydecisionsaboutwhat
theproperplaceboshouldbe.Second,theweightsattachedtothepotentialplacebocities
canbebasedonseveraleconomiccharacteristics.17
Idefineda“syntheticplacebo”byusingthreesuchcharacteristics:therateof
employmentgrowthinthe4-yearperiodpriortoMariel(i.e.,thevariableusedtodefinethe
employmentplacebo);theconcurrentrateofemploymentgrowthforhighschool
dropouts;andtheconcurrentrateofwagegrowthforhighschooldropouts.Thelasttwo
columnsofTable3reporttheseadditionalcharacteristics,showingthatMiamialsohada
robustlow-skilllabormarketpriortoMariel.Miamirankedsixthinthegrowthoflow-skill
employmentand13thintherateofwagegrowth.
Figure3alsoillustratesthewagetrendsinthe“city”thatmakesupthesynthetic
placebo.Aswillbeseenthroughoutthepaper,sometimesthetrendsfromthesynthetic
17Thesyntheticcontrolmethodstillrequirestheresearchertospecifythevectorofvariables(in
additiontothelabormarketoutcomeofinterest)thatshouldbesimilarbetweenMiamiandthesyntheticcityinthepre-treatmentperiod.
15
placeboresemblethosefromtheCardplacebo;sometimestheyresemblethosefromthe
employmentplacebo,andsometimestheyresembleneither.Muchdependsonthelabor
marketcharacteristicbeingexamined.
Itisinterestingtoexaminetheweightsimpliedbythesyntheticcontrolmethod(see
AppendixTableA-1foralisting).Whenthelabormarketinterestofoutcomeisthelog
wageofhighschooldropouts,thesyntheticcontrolmethodassignsthelargestweightsto
KansasCity(withaweightof0.56),Anaheim(0.27),Sacramento(0.041),andSanDiego
(0.013).Theappendixtablealsoreportstheweightsassignedbythesyntheticcontrol
methodintheregressionanalysisreportedbelow.Themetropolitanareaswiththelargest
weightsareAnaheim(0.372),SanDiego(0.239),Rochester(0.159),andSanJose(0.043).
BylookingattherankingofallthesecitiesinTable3,itisobviousthatthesyntheticcontrol
methodconsistentlyselectsmetropolitanareasthathadrobustlabormarketspriorto
Mariel(generatingsomeoverlapbetweenthecitiesthatmakeupthesyntheticcontroland
thecitiesintheemploymentplacebo).Figure3documentsthatacomparisonofwage
trendsbetweenMiamiandthesyntheticplaceboagainsuggeststhattheMiamiexperience
wasunique.
ThewagecomparisonsbetweenMiamiandthevariousplacebos,however,donot
precludethepossibilitythatothercitiesinothertimeperiodshaveexperiencedequally
steepwagecuts.Perhapstherearemanydocumentedcasesofsimilartransitoryand
numericallylargewagereductionsinothercitiesthatareattributabletosamplingerroror
tofactorsthathavenothingtodowithMariel.
Itiseasytoestablishthatthesteepdropinthelow-skillwageinpost-MarielMiami
wasaveryunusualevent.Theaveragewageofhigh-schooldropoutsinMiamifellby
around35percentbetween1976-1979and1981-1986.Wecancalculatethecomparable
wagechangeineveryothermetropolitanareaforallequivalenttimeperiodsbetween
1976and2003andseeiftheMiamiexperienceatthetimeofMarielstandsout.18
Obviously,if35-percentwagecutshappenfrequently,itwouldbehardertoclaimthat
18Garthwaite,Gross,andNotowidigdo(2014)conductasimilarexercisetoexaminethedistributionoftheimpactofanexperimentinhealthinsuranceavailabilityonemploymentlock.NotethatIextendthesampleperiodthrough2003todeterminehowthesteepwagedropobservedamonglow-skillMiamiansintheearly1980scomparestotheexperienceofcomparableworkersinallothermetropolitanareasoveratwo-decadeperiod.
16
Miami’sexperiencehadmuchtodowiththeMarielitos.Perhapssomethingelsewasgoing
on—a“somethingelse”thatoccursfrequentlyenoughinlocallabormarkets—thatjust
happenedtocoincidewiththetimingofCastro’sdecision.
ToassesshowMiami’spost-Marielexperiencecomparestothatoftheentire
distributionofwagechanges,Icalculatedthewagechangebetweeneverysingle“pre-
treatment”periodτ(1976-1979,1977-1980,…,1993-1996)andthecorresponding“post-
treatment”periodτ′(1981-1986,1982-1987,…,1998-2003).Notethattoreplicatethe
Marielexperiment,Iskipayearbetweenthe4-yearpre-treatmentspanandthe6-year
post-treatmentspan.Iconductedthiscalculationforeachmetropolitanarea,leadingtoa
totalof774possible“events”outsideMiami(43metropolitanareasand18potential
treatmentyearsbetween1980and1997).Ialsocalculatedthechangeinthelogwageof
theothereducationgroupsforallcity-yearpermutations.
ThetoppanelofFigure4illustratesthefrequencydistributionofallobserved
changesinthewageofhighschooldropoutsoutsideMiami.Table4reportssummary
statisticsfromthevariousdistributionscreatedbythisempiricalexercise.
Between1977-1979and1981-1986,thelogwageofhighschooldropoutsinMiami
fellby0.439logpoints(or35.5percent).ItisvisuallyobviousfromFigure4thatsucha
largewagedropwasanunusualevent.Themeanobservedwagechangeacrossallcity-
yearpermutationswasonlyabout-0.10logpoints.TheMarielexperienceranksinthe1.8th
percentileofthedistributionofallobservedwagechangesbetween1976and2003across
allmetropolitanareas.Similarly,thefrequencydistributionofobservedwagechangesfor
highschooldropoutsinthe1980treatmentyearshowsthatthewagedropobservedin
Miamiwasthelargestwagedropobservedamongallmetropolitanareas.
Equallyimportant,thisexerciserevealsthatmoreeducatedworkersinMiamidid
notexperienceasubstantialwagedecline(seethebottompanelofFigure4).Although
therehavebeenrecentclaimsthatperhapshighschooldropoutsandhighschoolgraduates
areperfectsubstitutesandshouldbepooledtoformthe“lowskill”workforce(moreon
thisinthenextsection),thedataclearlycontradictsthisconjecture.Themeanwagechange
inthelogwageofhighschoolgraduatesacrossallcity-yearpermutationsintheyears1977
through2001was-0.061,andMiami’sMarielexperiencerankedinthe66thpercentile.The
17
valueobservedintheMiamimetropolitanareaatthetimeofMarielwas-0.021,ranking
42ndoutofthe44metropolitanareasinthedistributionfortreatmentyear1980.
Inshort,somethinguniquehappenedtotheeconomicwellbeingofhighschool
dropoutsinMiamiintheearly1980s,butnottohighschoolgraduatesortoworkerswith
evenmoreeducation.TheeventthatshockedthewagestructureinMiamiatthetimeof
Mariel,whateverithappenedtobe,happensrarelyanditsadverseconsequenceswere
targetedverynarrowlyonworkerswholackedahighschooldiploma.
IV. Robustness of the Descriptive Evidence
Giventhestrikingpicturethattherawdatagivesaboutthelabormarketimpactof
theMarielitos,andgiventheverycontentiousdebateoverimmigrationpolicybothinthe
UnitedStatesandabroad,itisimportanttoestablishthattheevidencepresentedinthe
previoussectionisrobust.
Thissectionaddressesseveraldistinctquestionstoevaluatethesensitivityofthe
results.Forexample,wasthedeclineinthewageofhighschooldropoutsintheMiamiof
theearly1980srecordedbyothercontemporaneousdatasets,suchastheCPSOutgoing
RotationGroups(ORG)?Afterall,thetrendsinwageinequalityobservedintheORG
sometimesdiffermarkedlyfromthoseobservedintheMarchCPS.
Similarly,istheevidencerobusttoalternativedefinitionsofthelow-skill
workforce?Thedescriptiveanalysis,motivatedbytheeducationdistributionofthe
Marielitos,usedthesampleofhighschooldropoutstodefinethelow-skillworkforce.Are
thewagetrendssimilarifwedefinedalow-skillworkerdifferentlyorifweexaminedthe
shapeofMiami’swagedistribution?
1.ResultsfromtheCPS-ORG
Itiswellknown(Autor,Katz,andKearney,2008;Lemieux,2006)thatwagetrends
recordedbytheMarchCPSsometimesdifferfromthe“comparable”wagetrendsrecorded
bytheCPSOutgoingRotationGroups.UnliketheMarchCPS,whichmeasuresannual
earningsinthecalendaryearpriortothesurvey,theORGgivesameasureofthehourly
wageforrespondentswhoarepaidbythehourandoftheusualweeklywageforallother
18
workers.TheORGtimeseriesbeginsin1979,sothatthepre-treatmentperiodonly
containsoneyearofdata.FollowingAutor,Katz,andKearney(2008),Iextendthepre-
treatmentperiodbyusingtheroughlycomparable(thoughsmaller)MayCPSsupplements
for1977and1978. 19
ItisimportanttoemphasizethatthedifferencesinwagetrendsbetweentheMarch
CPSandtheORGarisepartlybecausethetwosurveysmeasuredifferentconceptsof
income.TheMarchCPSreportstotalearningsfromalljobsheldinthepreviouscalendar
year.TheORGmeasuresthewageinthemainjobheldbyapersonintheweekpriortothe
survey(ifworking).TheORGdoesnotprovideanyearningsinformationforpersonswho
happennottobeworkingonthatparticularweek,whereastheMarchCPSwouldcapture
theearningslossesassociatedwithjoblessperiods.Fromtheperspectiveofdetermining
thelabormarketimpactoftheMarielsupplyshock,itwouldseemthatthemore
encompassingmeasureoflabormarketoutcomesintheMarchCPSisfarpreferable.
Beforeproceedingtoexaminethepotentialdisparitiesinwagetrendsacrossthe
twosurveys,itisconvenienttofirstadjustthedatafordifferencesintheagedistributionof
workersindifferenttimeperiodsandindifferentmetropolitanareas.Tomaketheanalysis
transparent,Iusedasimpleregressionmodeltocalculatetheage-adjustedmeanwageofa
skillgroupinaparticularmarket.Specifically,Iestimatedthefollowingindividual-level
earningsregressionseparatelyineachCPScross-section:20
(1) logwirst=θr+Aiγt+ε,
wherewirstistheweeklywageofworkeriincityrineducationgroupsattimet;θrisa
vectoroffixedeffectsindicatingcityofresidence;andAiisavectoroffixedeffectsgiving
19Iusethe1979-2001ORGfilesarchivedattheNationalBureauofEconomicResearch.Becausethe
Maysupplementsbefore1977providelimitedinformationonmetropolitanareaofresidence,thewageseriesintheORGbeginsin1977whilethecomparableseriesintheMarchCPSbeginsin1976.ThewagemeasureusedintheORGanalysisistherecodedusualearningsperweek(earnwke).
20Ofcourse,theregressionsareestimatedseparatelyintheMarchCPSandtheORG.
19
theworker’sage.21Thefixedeffectsθrdeflatethelogweeklywageforregionalwage
differences.Theaverageresidualfromthisregressionforcell(r,s,t)givestheage-adjusted
meanwageofthatcell.Unlessotherwisespecified,Iuseage-adjustedwagesforthe
remainderofthepaper.22
Figure5illustratesthewagetrendscalculatedintheORGdataforMiamiandfor
thethreeplacebosdefinedintheprevioussection.23Itisagainvisuallyevidentthat
somethinghappenedtothelow-skilllabormarketinMiamiintheearly1980s,particularly
whentheMiamitrendiscomparedtoeithertheemploymentorsyntheticplacebos.The
useoftheCardplacebointheORGdataoftenmasksmuchofwhatwentoninpost-Mariel
Miami.
Forexample,thewageofhighschooldropoutsinMiamifellby0.22logpoints
between1979and1985.Figure5indicatesthatthecomparablewagefellby0.17log
pointsintheCardplacebo,andby-0.10logpointsineithertheemploymentorsynthetic
placebos.TheuseoftheCardplacebowouldimplythatMarielloweredthewageofhigh
schooldropoutsinMiamibyonlyabout5percent,whileboththeemploymentand
syntheticplaceboswouldimplyanimpactofaround12percent.Evenmoresothanthe
MarchCPSdata,theORGshowsthecrucialrolethatthechoiceofaplaceboplaysinany
measurementofthewageimpactoftheMarielitos.
2.Othermeasuresofskills
Somerecentstudiescontendthatmuchofthewageimpactofimmigration
disappearswhenthelow-skillgroupisdefinedinanalternativeway.Card(2009),for
example,arguesthathighschooldropoutsandhighschoolgraduatesareperfect
substitutes.24Thepoolingofthesetwogroupsintoaverylargelow-skillworkforce
21Iusedsevenagegroupstocreatethefixedeffects(25-29,30-34,35-39,40-44,45-49,50-54,and
55-59).
22Itisworthnotingthatthewagetrendsintheage-adjusteddataimpliedbytheMarchCPSlookalmostidenticaltotherawtrendsdocumentedinFigure2.
23ThelastcolumnofAppendixTableA-1showstheweightsattachedtothedifferentmetropolitanareasbythesyntheticplacebomethodintheORGdata.ThelargestweightswereattachedtoAnaheim(0.396),SanDiego(0.234),andRochester(0.164).
24SeealsoOttavianoandPeri(2012)andManacordaandManning(2012).
20
inevitablydilutesthedisparateimpactoflow-skillimmigrationontheleastskilledworkers,
andhelpsto“buildin”aconclusionthatrecentimmigrationcouldnothavehadmuchofan
impactonthewagestructure(Borjas,Freeman,andKatz,1997).
Puttingasidewhetherthetwogroupsareorarenotperfectsubstitutesforthe
moment,itisnonethelessimportanttoascertainiftheevidencethatMarielseemstohave
hadasubstantialwageimpactdisappearswhensuchanaggregationisconducted.Before
proceeding,however,itisworthemphasizingthattherawdatainFigure4indicatedthat
whilethewageofhighschooldropoutsinMiamifelldramaticallyafterMariel,thewageof
highschoolgraduatesdidnot(infact,itroserelativetowhathappenedelsewhere).The
twoeducationgroupswerealmostequallysizedinpre-MarielMiami,sothatthe
aggregationwillagaininevitablydilutetheimpactofMarielontheleast-educatedworkers.
Figure6usestheMarchCPSdatatoillustratethebasictrendsinthelogweekly
wageofthepooledgroupofhighschooldropoutsandhighschoolgraduates.Despitethe
factthattheaggregationattenuatessomeofthewageeffect,thefigureagainshowsa
differencebetweenwhathappenedtothisaggregatedlow-skillworkforceinMiamiand
elsewhere.Forexample,thewageofthepooledgroupofhighschooldropoutsand
graduatesfellby12percentinMiamiintheearly1980s,butbyonly5percentinthecities
thatmakeuptheemploymentplaceboand7percentinthesyntheticplacebo.
Itisimportanttonotethattheobservedwagetrendsrejecttheconjecturethatthe
twoeducationgroupsshouldbepooled.IfwestartwithanestedCESproductionfunction
andifwealsoassumethatwagesareequaltothevalueofmarginalproduct,itiswell
knownthattheelasticityofsubstitutionbetweenhighschooldropouts(group1)andhigh
schoolgraduates(group2)canbeestimatedbytheregression:
(2) log
w1
w2
⎛⎝⎜
⎞⎠⎟= λ− 1
σlog
L1
L2
⎛⎝⎜
⎞⎠⎟
,
wherewiisthewageofgroupi;Ligivesthenumberofworkersinthatgroup;andσisthe
elasticityofsubstitution.Thetypicalstudyexploitsvariationinfactorpricesandfactor
21
quantitiesacrossregionsorovertime(orboth)toestimateσ.Theinterceptλisafunction
oftechnologicalparameters,andneednotbeeitherregion-ortime-invariant.
Thevisualevidence(aswellastheregressionevidencepresentedinsubsequent
sections)suggeststhatthereislittleneedtotakethe“detour”ofestimatingequation(2)to
determineifhighschooldropoutsandhighschoolgraduatesareperfectsubstitutes.Ifwe
taketheCESframeworkseriously,equation(2)impliesthatthewageratioofthetwo
groupswillbeuncorrelatedwiththequantityratioonlyifσequalsinfinity.However,the
dataconsistentlyindicatesthatthewageofhighschooldropoutsinMiamirelativetothat
ofhighschoolgraduatesfelldramaticallyaftertheMarielsupplyshock.Thisdropinthe
relativewageofhighschooldropoutsisobviouslyinconsistentwiththehypothesisthatthe
twogroupsareperfectsubstitutes.Infact,aswehaveseenandwillseeagainbelow,the
impactofMarielonthewageofhighschooldropoutsisconsistentlynegative,whilethe
impactonhighschoolgraduatesismostlypositive.
The“experimental”wayofshowingthatthetwogroupsarenotproductiveclonesis
farmoreconvincingthanthetypicalregressionapproachusedtoestimateσ.Itiswell
knownthattherelativedemandforlow-skilllaborfellinrecentdecades,sothatthe
interceptλinequation(2)isnotconstantovertime.Weobviouslydonotknowhowtonet
outthisdemandshiftinatime-seriesdataset(suchastheonethatcouldbeconstructed
fromtheCPS),sothatassumptionsmustbemadeabouttheshapeoftheunobservedtrend
inrelativedemand.25Borjas,Grogger,andHanson(2012)showthatestimatesoftheslope
coefficientinequation(2)areextremelysensitivetotheseextraneousassumptions.The
estimateofσcanbemadepositive,zero,orevennegativebyassumingdifferentfunctional
formsfortheunobservedtrend,regardlessofwhethertheunderlyingwagedataareatime
25SeeKatzandMurphy(1992)andAutor,Katz,andKearney(2008).GoldinandKatz(2010)argue
thatthe“preferred”specificationfortheregressionmodelshouldincludealineartrendaswellasapost-1992splinetoaccountfortheseunobservedshiftsintherelativedemandofhighschooldropoutsandhighschoolgraduates.Ifone“buysinto”thesefunctionalformassumptions,theestimateof(-1/σ)usingtheGoldin-KatzannualCPSdatafrom1963through2005is-0.135(withastandarderrorof0.027),rejectingthehypothesisthatthetwogroupsareperfectsubstitutes(seeBorjas,Grogger,andHanson,2012).
22
seriesorexploitgeographicvariation.26TheMarielevidencethatsuggeststhetwogroups
arenotperfectsubstitutesisnotvulnerabletothiscriticism.
Finally,itisinstructivetoshowthatthewageofMiami’smostdisadvantaged
workersbehaveddifferentlyintheearly1980sevenifwedispensecompletelywiththeuse
ofeducationalattainmenttodefinethelow-skillworkforce.ItturnsoutthatMiamialso
experiencedawideningofitswagedistributionatthetime.Themosttransparentwayof
documentingthiswideningisbyexaminingwhathappenedtothespreadofthe
distributionoflogweeklyearningsinthevariouscities.
Figure7usestheMarchCPStoillustratethetrendinboththewageoftheworkerat
the20thpercentileaswellastheinterquantilerange,whichIdefineasthedifferenceinthe
logweeklywagebetweentheworkeratthe20thpercentileandtheworkeratthe80th
percentile.Thetrendsarevisuallystriking.Itisevidentthattheeconomicwellbeingof
Miamiansinthebottomtailofthewagedistributiontookabeatingpost-Mariel.Muchof
thedeclineseemedtooccurinthefirstfewyearsafterMariel,atwhichpointboththe
absoluteandrelativepositionoflow-skillworkersbegantorecover.
3.Implicationsfortheblack-whitewagegap
JustdayspriortotheMarielsupplyshock,the1980censusreportedthat25.2
percentofMiami’s(male)workforcewasAfrican-American.Therewas,however,asizable
disparityintheblackshareamongeducationgroups;itwas42.5percentforhighschool
dropouts,butonly6.0percentforcollegegraduates.Thisimbalanceintheskill
distributionsofblackandwhiteworkersinpre-MarielMiamisuggeststhatalargesupply
shockoflow-skillimmigrantswouldlikelyhaveadisproportionatelylargereffectonthe
blackworkforce,andcouldwidentheaveragewagegapbetweenblackandwhiteworkers.
TheimpactofMarielonMiami’sblackworkforceisofparticularinterestbecause
racialriotsravagedpartsofthecitywithinamonthaftertheMarielboatliftbegan,leaving
18deadand400injured.Theconditionsonthegroundwerevolatile,andtheriotswere
26Thetypicalregressionapproachalsofacesaseriousconceptualdifficulty:Whatexactlyisthe
exogenousforcethatgenerateschangesinrelativequantitiesthatsomehowcausechangesinrelativewages?Despitetheclassicsupply-demandendogeneityproblemwiththisregressionframework,theissuehasbeenalmostuniversallyignoredintheliterature.
23
theconsequenceofalonglistofaccumulatedgrievances,particularlytheacquittaloffour
whitepoliceofficerschargedwithmanslaughterwhenanAfrican-Americanmandiedafter
ahigh-speedchase.But,notably,oneofthegrievancescitedbyahistoryofthoseriotswas
“thedisplacementofblacksbyCubansfromjobsandotheropportunities”(Vogeland
Stowers,1991,p.120).
Figure8illustratesthetrendintheblack-whitewagegapinMiamiandtheplacebos
usingboththeMarchCPSandtheORGfiles.Itisobviousthattherelativeblackwage
declinedsharplyafterMariel.27TheMarchCPSdata,forexample,indicatesthattheblack
relativewageinMiamifellbyalmost20percentagepointsbetween1979and1985,
showingaverydifferenttrendthanwhatoccurredelsewhere.
ItisinterestingtonotethattheoriginalCardstudy,whichusedtheORGfiles,
suggeststhepossibilitythattheAfrican-AmericanworkforceinMiamiwasparticularly
affectedbytheMarielsupplyshock.Card(1990,Table3,p.250)reportsthattheblack
wageinMiamifellby11percentagepointsbetween1979and1983,ascomparedtoadrop
ofonly5percentagepointsinthecomparisoncities.Thissuggestiveevidence,however,
wasdismissed:“ThedatadosuggestarelativedownturninblackwagesinMiamiduring
1982-83.Itseemslikely,however,thatthisdownturnreflectsanunusuallyseverecyclical
effectassociatedwiththe1982-83recession.”Figure7showsthatthedownturninblack
wageswasnotatransitorycyclicaldeviation.Infact,thebottompanelofthefigureshows
thattheORGdatawouldhaverevealedacontinuingdeclineintheeconomicfortunesof
Miami’sblackworkershadtheCardstudyexaminedthedatabeyonditsstoppingpointof
mid-1985.
Inshort,itseemsasiftheimpactoftheMarielitosonrelativewagesacross
educationgroupssubstantiallyworsenedtherelativeeconomicstatusofthetypical
African-AmericaninMiamirelativetohiscounterpartintheplacebocities.This
disproportionateimpactoflow-skillimmigrationontheAfrican-Americanworkforceis
consistentwiththeevidencereportedinBorjas,Grogger,andHanson(2010).
27Thecalculationofthesyntheticplacebowasnotconductedfortheblack-whitewagegapintheMarchCPSbecausethemethodologyrequiresaperfectlybalancedpanelovertherelevantsampleperiod.Unfortunately,therewereover10city-yearpermutationsinthedatathatdidnotsampleanyblackworkers.Therewereonly3city-yearpermutationswithoutblackworkersintheORG(andtheywereallin1977or1978).Iusedadjacent-yeardatatoimputethemissinginformationfortheORG.
24
ItwouldbeofgreatinteresttoalsoexaminetherelativetrendsinHispanicwages,
butthenatureoftheavailabledatawouldmakethatcomparisonuninformative.A
replicationoftheanalysisillustratedinFigure8fortheHispanicpopulation(notshownfor
thesakeofbrevity)wouldshowsteadywagedeclinesforHispanicworkersthroughoutthe
entireperiodinMiamiandinthevariousplacebos.The1980sand1990swereaperiodof
substantialHispanicimmigrationintomanyareasofthecountry,andthatinfluxincluded
millionsofundocumentedimmigrantswhoarealsodisproportionatelylikelytobehigh
schooldropouts.Manyoftheplacebocitiesalsoreceivedlargenumbersoflow-skill
Hispanicimmigrants,dilutingtheireffectivenessasacontrolgroup.Moreover,theCPSdata
doesnotallowustocreateasampleof“pre-existing”Hispanicworkers,sothatthe
observedtrendintheHispanicwageislargelyreflectingthechangingcompositionofthe
Hispanicworkforceduetothepersistentinflowoflargenumbersofimmigrants.
V. Regression Results Toestimatethepost-treatmenteffectoftheMarielsupplyshockrelativetothe
variousplacebos,Iusethemeanage-adjustedwageofhighschooldropoutsincityrattime
t,denotedby logwrt .Thiswagebecomesthedependentvariableinatraditionaldifference-
in-differencesregressionmodel:
(3) logwrt = θr + θt +β(Miami× Post-Mariel)+ ε,
whereθrisavectorofcityfixedeffects;θtisavectorofyearfixedeffects;“Miami”
obviouslyrepresentsadummyvariableindicatingtheMiami-Hialeahmetropolitanarea;
and“Post-Mariel”indicatesiftimetoccursafter1980.
Theregressionusesannualobservationsbetweent=1977andt=1992,butexcludes
1980,theyearofthesupplyshock.28ThecitiesrincludedintheregressionareMiamiand
thecitiesinaspecificplacebo.Forexample,iftheMiamiexperienceisbeingcomparedto
thatofcitiesintheemploymentplacebo,therewouldbefivecitiesinthedata,andeachof
28ThistimespanallowsmetoestimatetheidenticalregressionmodelinboththeMarchCPSandORGsamples.
25
thesecitieswouldbeobserved15timesbetween1977and1992,foratotalof75
observations.TheregressioncomparingMiamitothesyntheticplaceboissimilarinspirit,
butthereareonlytwo“cities”inthisregression:Miamiandthesyntheticcity,foratotalof
30observations.
ToallowthewageimpactofMarieltovaryovertime,the“post-Mariel”variablein
equation(3)isavectoroffixedeffectsindicatingwhethertheobservationrefersto1981-
1983,1984-1986,1987-1989,or1990-1992.Table5reportstheestimatedcoefficientsin
thevectorβforvariousspecificationsoftheregressionmodelusingtheMarchCPSdata.
Thetablealsoreportsrobuststandarderrorsthatcorrectforheteroscedasticity.Itislikely
thatthereisserialcorrelationinoutcomesatthecitylevelthatwouldrequirefurther
adjustmentsforvalidstatisticalinference,butitiswellknown(CameronandMiller,2015)
thatclusteredstandarderrorsaredownwardbiasedwhentherearefewclustersinthe
data.
ConsiderinitiallytheregressionsreportedinPanelAofthetable,wherethe
dependentvariableistheage-adjustedlogweeklywageofhighschooldropoutsincityrat
timet.Thevariouscolumnsofthetableusealternativeplacebos:theCardplacebo,the
employmentplacebo,thesyntheticplacebo,aswellasanaggregateplacebocomposedof
allother43metropolitanareas.Thevariousrowsreportthecoefficientsinthevector
β indicatinghowthewageimpactvariesduringthepost-Marielperiod.Thetrendinthese
coefficientspresumablycapturesthewageeffectastheMiamilabormarketadjusts,and
movesfromthe“short”tothe“long”run.
ItisevidentthatthecoefficientβestimatedimmediatelyafterMarielisnegative,
indicatinganabsolutedeclineinthewageoflow-skillworkersintheaftermathofthe
supplyshock.However,theeffectismuchsmallerwhenIusetheCardplacebothanwhenI
useeithertheemploymentorsyntheticplacebo.Theimmediatewagecutusingtheoriginal
Cardplacebois-0.137(0.093),whilethewagecutimpliedbytheemploymentplacebois
twiceaslarge,withapointestimateof-0.289(0.090),andthewagecutimpliedbythe
syntheticplacebois-0.210(0.086).Itseems,therefore,thatthewageofhighschool
dropoutsinMiamifellby20to25percentintheimmediateshortrun(1981-1983).
Remarkably,thiswageeffectincreasesinthenextthreeyears,sothatthewageforhigh
26
schooldropoutsfellby40percentwithin5years(usingeithertheemploymentor
syntheticplacebos).Thewageeffectthenbeginstoweaken,andessentiallydisappearsby
the1990-1992period,whenthecoefficientinthesyntheticplaceboregressionis0.021
(0.096).
PanelsBandCofthetablereplicatetheanalysisusingthetwoalternativemeasures
ofrelativewages.Bothpanelssuggestthattherelativewageoftheleasteducatedworkers
typicallyfellimmediatelyafterthesupplyshock,withthewageofhighschooldropouts
fallingbyasmuchas30percentrelativetohighschoolgraduates.Aswiththeabsolute
wageresults,therelativewageeffectalsodisappearsbytheearly1990s.
Table6reportsthecoefficientsfromcomparableregressionsusingtheORGdata.
TheimmediateeffectonthewageofhighschooldropoutsimpliedbytheORGisroughly
similartothatimpliedbytheMarchCPSwhenIuseeithertheemploymentplaceboorthe
syntheticplacebo.Thelogwageofhighschooldropoutsfellby20to25percentinthe
MarchCPSdataandby15to20percentintheORG.Thereisoneinterestingdifferencein
theORGregressionresults:ThewageeffectoftheMarielitosdoesnoteventuallydisappear.
Boththeemploymentandsyntheticplacebosindicatethatthelogwageofhighschool
dropoutsinMiamiis10to20percentbelowthatofcomparableworkersintheplacebo
citiesevenadecadeyearsafterMariel(althoughtheeffectisnotsignificantwiththe
employmentplacebo).
DespitetheregressionfindingthattheMarielsupplyshockharmedlow-skill
workersintheshortrun,theoverallevidencemaynotbeconsistentwiththetextbook
modeloffactordemand.Theevidenceconsistentlysuggeststhattheadversewageeffectof
theMarielitosinitiallyincreasedovertimebeforeeventuallydisappearing.Thisishardto
squarewiththetheoreticalpredictionthatthewageeffectwouldbelargestrightafterthe
supplyshockandwouldweakenasthecapitalstockadjustedovertime.Onepossible
explanationmaybethatemployersarereluctanttocutwagesforpre-existingworkers,so
thattheimmigration-inducedwagecutscomeintoplay“slowly”asturnoverinthelowskill
labormarketallowsfirmstotakeadvantageofthechangedsituation.
Equallyimportant,theadjustmentsinducedbytheMarielsupplyshockprobably
involvedmuchmorethantheincreaseinthecapitalstockthatplaysthecentralroleinthe
neoclassicalmodeloflabordemand.AssuggestedbytheracialunrestthatshookMiami
27
soonafterMariel,thepoliticalandsocialupheavalcreatedbyCastro’sdecisiontoopenup
theportofMarielaffectedMiami’seconomyinwaysthatextendfarbeyondwhatour
modelscapture(PortesandStepick,1994).Putdifferently,theceterisparibusassumption
doesnotreallyapply.Giventheseundocumentedandunknownreactions,itisdifficultto
saymuchaboutthedynamicsofthewageeffectfromtheevidencegeneratedbytheMariel
supplyshock.
Wealsodonotfullyunderstandthefactorsresponsiblefortheeventual
disappearanceoftherelativewageeffect(atleastintheMarchCPS).Economictheory
impliesthatitistheaveragewageinthelabormarketthatwillreturntoitspre-Mariel
leveliftheproductionfunctionislinearhomogeneous(Borjas,2014).Therelativewage
effectwillnotgoawayunlesstherehasalsobeenachangeintherelativequantitiesoflow-
andhigh-skilllabor.Card(1990,p.255)citesevidencethatinsinuatesapossiblesupply
response:“TheBoatliftmayhaveactuallyheldbacklong-runpopulationgrowthin
Miami…thepopulationofDadeCountyin1986wasaboutequaltothepre-Boatlift
projectionoftheUniversityofFloridaBureauofEconomicandBusiness.”Although
suggestive,thisslowdowninpopulationgrowthcannotexplaintheabsenceofalong-term
relativewageeffectunlesstheslowdownalsoresultedinarelative“exodus”oflow-skill
workersfromtheMiamilabormarket.
Finally,Table7summarizesregressioncoefficientsfrommodelsthatdefinethelow-
skillworkforceinalternativeways.Tosimplifythepresentation,Iestimatedtheregression
modelinequation(3)usingonlytheyearsbetween1977and1986(excluding1980),and
theshort-runwageeffectreportedinthetableissimplytheinteractionbetweenthe
indicatorfortheMiamimetropolitanareaandtheindicatorforapost-1980observation.
Althoughthereisobviouslyalotofvariationintheestimatedcoefficients(andstatistical
significance),thethrustoftheevidencesuggestsanegativeshort-runimpactregardlessof
whetherwelookatthelogwageofhighschooldropouts,thelogwageofthepooledgroup
ofhighschooldropoutsandhighschoolgraduates,theinterquantilerange,ortheblack-
28
whitewagegap.TheMarielsupplyshocktypicallyharmedworkersatthebottomendof
thewagedistribution.29
Theuseofeithertheemploymentplaceboorthesyntheticplaceboindicatesthatthe
wageofhighschooldropoutsinMiamifellby10to30percent(dependingonthedataset
used)duringthefirst6yearsafterMariel.AsInotedearlier,thesupplyshockincreasedthe
numberofhighschooldropoutsbyaround20percent,sothattheimpliedwageelasticity
(dlogw/dlogL)isbetween-0.5and-1.5.
Eitheroftheseelasticityestimatesisfarhigherthanthetypicalwageeffect
estimatedin(non-experimental)cross-cityregressionsthatlinkwagestoimmigration,an
effectthatoftenclustersaroundanegligiblenumber.Theyarealsohigherthanthewage
elasticitiesestimatedbycorrelatingwagesandimmigrationacrossskillgroupsinthe
nationallabormarket(Borjas2003),anelasticitythatclustersaround-0.3to-0.4.
Interestingly,theestimatesareclosetothosereportedinMonras(2015)andLlull(2015),
whousenewinstruments(includingthePesoCrisisinMexico,naturaldisasters,armed
conflicts,andchangesinpoliticalconditions)tocorrectfortheendogeneityofmigration
flows.Monrasreportsawageelasticityof-0.7andLlull’sestimatesclusteraround-1.2.
Thereareobviouslymanycaveatsthatneedtobeconsideredregardingthe
specificationoftheregressionmodelsandthesmallsamplesintheCPSdatabeforewefully
buyintoanelasticityestimateofbetween-0.5and-1.5.Nevertheless,thekeyimplicationof
theevidenceisunambiguous.ThewageofhighschooldropoutsintheMiamilabormarket
fellsignificantlyaftertheMarielsupplyshock.Anyattemptatrationalizingthisfactasdue
tosomethingotherthantheMarielitoswillneedtospecifypreciselywhatthoseother
factorswere.
29Ialsoestimatedspecificationsoftheregressionmodelthatuseddifferentvectorsofvariablesto
predictthesyntheticplacebo.Averygeneralspecification,forexample,includedthetotalgrowthrateofemploymentinthemetropolitanarea,theemploymentandwagegrowthratesforeachofthefoureducationgroups,thepercentoftheworkforcethatwasblack,andthepercentthatwasHispanic.Theestimatedshort-runwageeffectwas-0.148(0.059)intheMarchCPSand-0.134(0.079)intheORG.Theweightingalgorithmintheseexpandedregressions,particularlywhenincludingthepercentHispanicvariable,oftenassignedverylargeweightstoSanDiego.
29
VI. The Choice of a Placebo Theevidencereportedintheprevioussectionssuggeststhatthechoiceofaplacebo
matters.Theshort-runimpactoftheMarielsupplyshock(i.e.,theimpactonwages
between1981and1986)wasgenerallymorenegativeandstatisticallysignificantwhenI
usedeithertheemploymentorsyntheticplacebothanwhenIusedtheCardplacebo.Itis
usefultodocumentinaverysimplewayhowitispossibleto“cherrypick”placebosto
buildinaparticularempiricalfinding.Iillustratethisvariationbyestimatingtheshort-run
wageeffectusingthedifference-in-differencesregressionmodelinequation(3)ineachof
the123,410possiblefour-cityplacebos.BecauseIamfocusingontheshort-runwage
impact,theregressionsonlyemploytheobservationsbetween1977and1986(withthe
1980observationexcludedthroughout).
ThetwopanelsofFigure9illustratethefrequencydistributionofestimatedeffects
whenthedependentvariableisthelogwageofhighschooldropouts,whileTable8reports
summarystatisticsforthevariousdistributions.Forcomparisonpurposes,thebottom
rowsofthetablereporttheactualestimatedwageimpact(andstandarderror)whenusing
theCard,employment,andsyntheticplacebos.
Considerthedistributionofestimatedeffectsonthewageofhighschooldropoutsin
theMarchCPSdata.Themeaneffectis-0.243,whichisfarsmallerthantheestimate
obtainedfromeithertheemploymentplacebo(-0.374)orthesyntheticplacebo(-0.335).
Nevertheless,mostofthepotentialplaceboswouldstillsuggestthatthewageeffectis
significant:over98percentoftheestimatedeffectshaveat-statisticabove1.6.
Note,however,thatifthesetofplaceboswererestrictedsothattheaverage
employmentgrowthinthefourplacebocitieswasroughlysimilartothatofpre-Mariel
Miami,themeanwageeffectrisesto-0.282.Similarly,ifwelookatthestillsmallersubset
ofplaceboswhereeachcityintheplacebohadasimilarpre-Marielemploymentgrowthas
Miami,theestimatedwageeffectbecomesevenstronger;themeancoefficientis-0.333,
andallofthosecoefficientsarestatisticallysignificant.Putdifferently,thecloserwegettoa
placebothatseemstoreplicatethepre-existingemploymentconditionsinMiami,themore
likelywearetofindthattheMarielitoshadanumericallysizableandastatistically
significantwageeffectonlow-skillMiamians.AsTable8shows,thesamegeneraltrendis
impliedbythefrequencydistributionofwageeffectscomputedintheORGdata.
30
Thistypeofunusualexerciseshowstheimportancethatthechoiceofaplacebo
playsingeneratingestimatesoftheimpactofnaturalexperiments.Itmightbeprudentto
withholddrawingmanysubstantiveinferencesfromsuchexperimentsuntilweseehow
the“preferred”estimateofthepolicyimpactcomparestothedistributionofpotential
impacts.30
Itisinstructivetoconcludebyextendingthesyntheticcontrolapproachtoshowthe
distributionofwageeffectsimpliedbyanintriguingcounterfactualexercise.Whatwould
thedistributionofestimatedwageeffectslooklikeifwe“actedasif”acityhadexperienced
ashockinyeart,andsimplycalculatedthepre-postwagechangeattributabletothis
imaginarysupplyshock?
Tobemorespecific,supposewedefineapre-treatmentperiodof3yearsandapost-
treatmentperiodof6years.WecanimaginethatthecityofAkronwashitbyaphantom
supplyshockin1988.WecanthencalculatethewagechangeexperiencedbyAkron
between1985-1987and1989-2004,andcontrastthiswageeffectwithwhathappenedto
wagesinthesyntheticplaceboimpliedbythepre-existingconditionsinAkron.31
Presumably,thewageeffectresultingfromthisexerciseshouldbenearzerosimply
becauseFidelCastrodidnotsuddenlydecidetorelocateover100,000CubanstoAkronin
1988.However,other(random)thingsmayhavehappenedinpost-1988Akronthatwe
knownothingaboutandthatmayhavechangedtherelativewageoflow-skillworkersin
thatcityrelativetothesyntheticplacebo.
Wecanobviouslycarryoutthisexerciseforeverysinglepermutationofacity
receivinganimaginarysupplyshockandeverysinglepre-postperiodallowedbythedata
between1977and2003.Togeneratethesyntheticcontrol,Iusedthecity’srateoftotal
employmentgrowthinthe4-yearperiodpriortothetreatment,andtheratesof
employmentandwagegrowthforthespecificeducationgroupbeingexamined.Thetop
panelofFigure10illustratesthedistributionoftheestimatedwageeffectsofthese
30Thereis,infact,astrongnegativecorrelationbetweenthewageeffectestimatedinplacebopand
themeanrateofemploymentgrowthinthecitiesthatformthatplacebo.
31TobeconsistentwiththeanalysisoftheMarielsupplyshock,thepre-treatmentemploymentgrowthismeasuredinthefour-yearperiodpriortothehypotheticalshock,or1985-1988intheAkronexamplediscussedinthetext.
31
hypotheticalshocksusingthelogwageofhighschooldropoutsasthedependentvariable,
andTable9summarizessomeofthecharacteristicsoftheresultingdistributions.Thedata
reportedinTable9,ofcourse,allowapermutationinferenceanalysisofthewageeffectof
theMarielsupplyshock.
Thereisobviouslyalotofdispersionintheestimatedwageeffectsacrossallthese
hypotheticalshocks.Asexpected,themeaneffectiszero.Itisimportanttoemphasize,
however,thattheMarchCPSimpliesthatthewageeffectinducedbytherealMarielsupply
shockinMiamiwas-0.335(0.090),whichisinthe3rdpercentileofthecounterfactual
distributionwhereeachimaginaryshockiseffectivelybeingcomparedtothe“best”
possibleplaceboforthatcityatthattime.Ifwenarrowdownthecomparisontothe1980
treatmentyear,theMarieleffectisbythemostnegativeacrossallmetropolitanareas.
Itisalsoinstructivetodocumentthewageimpactontheothereducationgroups
resultingfromthiscounterfactualexercise.AsthelastthreecolumnsofTable9show,the
meaneffectsacrossallcity-yearpermutationsarealwaysnearzero,andtheeffect
observedinMiamiatthetimeofMarielistypicallynotsignificantlydifferentfromzero.
Nevertheless,asthebottompanelofFigure9illustrates,theimpactofMarielonthewage
ofhighschoolgraduatesispositive,againrejectingtheconjecturethathighschool
graduatesandhighschooldropoutsareperfectsubstitutes.
Finally,Figure11illustratesthedynamicsoftheestimatedwageeffectresulting
fromtheMarielsupplyshockinMiami,andfromthehypotheticalsupplyshocksinallother
metropolitanareasinthe1980treatmentyear.Specifically,Iusethesyntheticcontrol
methodandcalculateforeachmetropolitanareaineachyearthrough1992thepre-post
differencebetweenthewageofhighschooldropoutsinaspecificmetropolitanareaandin
itssyntheticplacebo.Thecalculateddoubledifference,ofcourse,impliesthateachpointin
thefiguremeasuretheimpactofthesupplyshockonthewageofhighschooldropoutsas
oftimet.Forexample,thetrendintheMiamiwageeffectimpliedbytheMarchCPSdata
indicatesthatthewageofhighschooldropoutsinMiamirelativetothesyntheticplacebois
around30percentlowerin1985thanitwasin1979.Notethatthetrendforthewage
effectintheMiamimetropolitanareafromashockintreatmentyear1980formsalower
“envelope”fortheentiredistributionofpotentialwageeffectsresultingfrom
contemporaneoussupplyshocksinallothermetropolitanareas.Thisexerciseagainshows
32
thatthewageeffectoftheMarielitosdisappearsafteradecadeintheMarchCPSdata,but
persistsintheORG.
Insum,theMarielsupplyshockhadaveryspecifictargetandithitthattargetwith
impressivelaser-likeprecision:TheMarielitoshadasubstantialdepressingeffectonthe
earningsoftheleasteducatedworkersinMiami.
VII. Conclusion Card’s(1990)classicpaperonthelabormarketimpactoftheMarielsupplyshock
standsasalandmarkstudyinlaboreconomics.Hisfindingthatthesupplyshockseemedto
havelittleeffectonthelabormarketopportunitiesofnativeworkershasprofoundly
influencedwhatwethinkweknowabouttheeconomicconsequencesofimmigration.The
eleganceofthemethodologicalapproach—theexploitationofafascinatingnatural
experimenttoestimateaparameterofgreateconomicinterest—hasalsoinfluencedthe
waythatmanyappliedeconomistsframetheirquestions,organizethedata,andsearchfor
ananswer.
ThispaperbringsanewperspectivetotheanalysisoftheMarielsupplyshock.I
revisitthequestionandthedataarmedwiththeinsightsprovidedbythreedecadesof
researchontheeconomicimpactofimmigration.Onekeylessonfromthisvoluminous
literatureisthattheeffectofimmigrationonthewagestructuredependscruciallyonthe
differencesbetweentheskilldistributionsofimmigrantsandnatives.Thedirecteffectof
immigrationismostlikelytobefeltbythoseworkerswhohadsimilarcapabilitiesasthe
Marielitos.
ItiswellknownthattheMarielsupplyshockwascomposedofdisproportionately
low-skillworkers,andatleast60percentwerehighschooldropouts.Remarkably,noneof
thepreviousexaminationsoftheMarielexperiencedocumentedwhathappenedtothepre-
existinggroupofhighschooldropoutsinMiami,agroupthatcomposedoveraquarterof
thecity’sworkforce.GiventheliteraturesparkedbyBorjas(2003),itseemsobviousthata
crucialcomponentofanyanalysisoftheMarielsupplyshockshouldfocusonthelabor
marketoutcomesoftheselow-skillworkers.
33
Theexaminationofwagetrendsamonghighschooldropoutsquicklyoverturnsthe
“stylizedfact”thatthesupplyshockdidnotaffectMiami’swagestructure.Infact,the
absolutewageofhighschooldropoutsdroppeddramatically,asdidtheirwagerelativeto
thatofeitherhighschoolgraduatesorcollegegraduates.Thedropintheaveragewageof
theleastskilledMiamiansbetween1977-1979and1981-1986wassubstantial,between
10and30percent(dependingonwhethertheanalysisusestheCPS-ORGortheMarchCPS
data).Infact,theexaminationofwagetrendsineverysinglecityidentifiedbytheCPS
throughouttheperiodshowsthatthesteeppost-MarielwagedropexperiencedbyMiami’s
low-skillworkforcewasaveryunusualevent.
Thereappraisalpresentedinthispaperalsostrikinglyillustratesthatthe
researcher’schoiceofaplaceboisanimportantcomponentofanysuchempiricalexercise,
andthatpickingthe“wrong”placebocaneasilyleadtoaweakermeasuredimpactof
immigration.Theanalysisdocumentedtheimportanceofplacebochoicebyestimatingthe
impactofMarielacrossallpotential(four-city)placebosallowedbythedata.The
distributionofestimatedwageeffectsisveryinformative.Themeasuredwageimpactof
thesupplyshockislargestwhenthecomparisongroupconsistsofcitiesthathadasimilar
rateofpre-MarielemploymentgrowthasMiami.Themethodologicalapproachof
estimatingtheentiredistributionofpotentialeffectsacrossallpossibleplaceboscanbea
usefulcomponentofstudiesthatexaminetheconsequencesofnaturalexperiments.
Theempiricalevidencealsohasmanylessonsforthevastliteraturethatpurportsto
measurethewageimpactofimmigration.Forinstance,manystudiesmeasuretheeffectby
estimatingspatialcorrelationsbetweenwagesandthenumberofimmigrantsina
particularlocality.Thesespatialcorrelations,manyofwhichclusteraroundzero,are
plaguedbothbyendogeneityproblems(i.e.immigrantssettleinhigh-wageregions)andby
nativeadjustments(i.e.,firmsandworkersmayrespondtothesupplyshockbyrelocating
toothercities).ThefactthatthespatialcorrelationimpliedbytheMarielsupplyshockis
stronglynegativesuggeststhattheexistingnon-experimentalliteraturehasnot
successfullypurgedthosestatisticaldifficulties.Thereisstillsomewaytogobeforenon-
experimentalspatialcorrelationscanbepresumedtoestimateaparameterofeconomic
interest.
34
Theevidencealsohaspotentiallyimportantimplicationsforestimatesofthe
economicbenefitsfromimmigration.Thebenefitthataccruestothenativepopulation,or
the“immigrationsurplus,”istheflipsideofthewageimpactofimmigration.Infact,itis
wellknownthatthegreaterthewageimpact,thegreatertheimmigrationsurplus.Borjas
(2014,p.151)estimatesthecurrentsurplustobearound0.24percentofGDP(oraround
$43billionannually).Thefactthattherewasamuchlargerreductionintheearningsofthe
workersmostlikelytobeaffectedbytheMarielitosthanwaspreviouslybelievedsuggests
thatwemayalsoneedtoreassessexistingestimatesoftheimmigrationsurplus.That
surpluscouldeasilybetwiceorthreetimesaslargeiftheMarielcontextcorrectly
measuresthewageimpact.
Ithasbeenaquarter-centurysincethepublicationofCard’sMarielstudy.More
likelythannot,thatanalysishasbeenreplicatedoftenaspartofanempiricalexerciseinan
econometricsorlaboreconomicsclass.Thereappraisaloftheevidenceprovidedinthis
paperteachesanimportantlesson.Althoughreplicationobviouslyservesanextremely
usefulroleintheadvancementofappliedscience,thereismuchtobegainedbyrevisiting
manyofthosepersistentoldquestionswithanewperspective,aperspectivethatusesthe
insightsaccumulatedovertheyears.Ifnothingelse,thereappraisaloftheMarielevidence
showsthateventhemostcursoryreexaminationofsomeolddatawithsomenewideascan
revealtrendsthatradicallychangewhatwethinkweknow.
35
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Ottaviano,GianmarcoI.P.,andGiovanniPeri.2012.“RethinkingtheEffectofImmigrationonWages.”JournaloftheEuropeanEconomicAssociation10:152-197.
Portes,AlejandroandAlexStepick.1994.CityontheEdge:TheTransformationof
Miami.Berkeley,CA:UniversityofCaliforniaPress.Saiz,Albert.2003.“RoomintheKitchenfortheMeltingPot:ImmigrationandRental
Prices.”ReviewofEconomicsandStatistics85:502-521.Stabile,BenedictL.,andRobertL.Scheina.2015.“U.S.CoastGuardOperations
Duringthe1980CubanExodus,”U.S.CoastGuardwebsite,accessedSeptember30,2015.
Vogel,RonaldK.,andGenieN.L.Stowers.1991.“Miami:MinorityEmpowermentandRegimeChange,”inH.V.SavitchandJohnClaytonThomas,eds.,BigCityPoliticsinTransition.NewYork:SagePublications.
38
Figure1.NumberofCubanimmigrants,byyearofmigration,1955-2010
Notes:Thespecificyearofmigration(through1999)isfirstreportedinthe2000census.Thecountsareadjustedformortalityandout-migrationbyusinginformationonthenumberofarrivalsprovidedbythe1970through1990censuses;seethetextfordetails.The2000-2008countsaredrawnfromthepooled2009-2011AmericanCommunitySurveys(ACS),whilethe2009-2010countsaredrawnfromthe2012ACS.
0"
10,000"
20,000"
30,000"
40,000"
50,000"
60,000"
70,000"
80,000"
90,000"
100,000"
110,000"
120,000"
1950" 1960" 1970" 1980" 1990" 2000" 2010"
Num
ber'o
f'immigrants'
Year'of'migra1on'
39
Figure2.Logwageofhighschooldropouts,1972-2003
Notes:Thelogweeklywageisa3-yearmovingaverageoftheunadjustedaveragelogwageofhighschooldropoutsineachgeographicarea.ThedataaredrawnfromtheMarchCPSfiles.
5"
5.1"
5.2"
5.3"
5.4"
5.5"
5.6"
5.7"
5.8"
5.9"
1970" 1975" 1980" 1985" 1990" 1995" 2000" 2005"
Log$weekly$wage$
Year$
Miami
Outside Miami
40
Figure3.Thetrendinthewageoflow-skillworkers,1976-1992
A. Log weekly wage of high school dropouts
B. Log wage of high school dropouts relative to college graduates
C. Log wage of high school dropouts relative to high school graduates
Notes:Thefiguresusea3-yearmovingaverageoftheage-adjustedaveragelogwageofhighschooldropouts,highschoolgraduates,andcollegegraduatesineachspecificgeographicarea.ThedataaredrawnfromtheMarchCPSfiles.
5"
5.1"
5.2"
5.3"
5.4"
5.5"
5.6"
5.7"
5.8"
5.9"
1976" 1978" 1980" 1982" 1984" 1986" 1988" 1990" 1992"
Log$weekly$wage$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
!1.2%
!1%
!0.8%
!0.6%
!0.4%
!0.2%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
!0.7%
!0.6%
!0.5%
!0.4%
!0.3%
!0.2%
!0.1%
0%
0.1%
0.2%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami Synthetic placebo
Card placebo
Employment placebo
41
Figure4.Distributionofpre-postwagechanges,1976-2003
A. Log wages of high school dropouts
Across all city-year permutations 1980 treatment year
B. Log wage of high school graduates
Across all city-year permutations 1980 treatment year
Notes:Thepre-treatmentperiodlasts4years;thepost-treatmentperiodlasts6years;andtheyearofthetreatmentisexcludedfromthecalculation.ThedataaredrawnfromtheMarchCPSfiles.
Mariel Mariel
Mariel Mariel
42
Figure5.Thetrendinthewageoflow-skillworkersintheORG,1977-1992
A. Log weekly wage of high school dropouts
B. Log wage of high school dropouts relative to college graduates
C. Log wage of high school dropouts relative to high school graduates
Notes:Thefiguresusea3-yearmovingaverageoftheage-adjustedaveragelogwageofhighschooldropouts,highschoolgraduates,andcollegegraduatesineachspecificgeographicarea.
!0.6%
!0.5%
!0.4%
!0.3%
!0.2%
!0.1%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$weekly$wage$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
!1#
!0.9#
!0.8#
!0.7#
!0.6#
!0.5#
!0.4#
!0.3#
1976# 1978# 1980# 1982# 1984# 1986# 1988# 1990# 1992#
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
!0.5%
!0.4%
!0.3%
!0.2%
!0.1%
0%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
43
Figure6.Wagetrendsinpooledgroupofhighschooldropoutsandhighschoolgraduates,MarchCPS,1977-1992
A.Logwageofpooledhighschooldropoutsandhighschoolgraduates
B.Logwageofpooledhighschooldropoutsandgraduatesrelativetocollegegraduates
Notes:Thefiguresusea3-yearmovingaverageoftheage-adjustedaveragelogwageofthepooledgroupofhighschooldropoutsandhighschoolgraduates,andofcollegegraduatesineachspecificgeographicarea.
!0.4%
!0.3%
!0.2%
!0.1%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
!0.9%
!0.8%
!0.7%
!0.6%
!0.5%
!0.4%
!0.3%
!0.2%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
44
Figure7.Trendsinthespreadofthelogweeklywagedistribution,MarchCPS,1977-1992
A.Logwageofworkeratthe20thpercentile
B.Differenceinthelogwageofworkersatthe20thand80thpercentiles
Notes:Thefiguresusea3-yearmovingaverageoftheage-adjustedlogweeklywageineachspecificgeographicareaforeachspecificpercentile.
!0.7%
!0.6%
!0.5%
!0.4%
!0.3%
!0.2%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
!1.3%
!1.2%
!1.1%
!1%
!0.9%
!0.8%
!0.7%
!0.6%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Synthetic placebo
Card placebo
Employment placebo
45
Figure8.Trendsintheblack-whitewagedifferential,1976-1992A.MarchCPS
B.CPS-ORG
Notes:Thefiguresusea3-yearmovingaverageofthedifferenceintheage-adjustedaveragelogwagebetweenblackandwhiteworkersineachspecificgeographicarea.
!0.8%
!0.7%
!0.6%
!0.5%
!0.4%
!0.3%
!0.2%
!0.1%
1976% 1978% 1980% 1982% 1984% 1986% 1988% 1990% 1992%
Log$wage$gap$
Year$
Miami
Card placebo
Employment placebo
-0.7
-0.6
-0.5
-0.4
-0.3
-0.2
-0.1
1976 1978 1980 1982 1984 1986 1988 1990 1992
Logwagegap
Year
Miami
Card placebo
Employment placebo Synthetic placebo
46
Figure9.Distributionofshort-runimpactsacrossallpossiblefour-cityplacebos,1977-1986
A.MarchCPS
B.CPS-ORG
Notes:Thefigureshowsthedistributionoftheinteractiontermfromthedifference-in-differencesregressionmodelinequation(3)resultingfromcomparingMiamitoallpossible123,410placebosintheMarchCPSdata.Theregressionsuseannualobservationsforeachcityintheperiod1977-1986(1980excluded),andthecoefficientsmeasuretheimpactinthe“shortrun”(i.e.,1981-1986).Allregressionswereweightedbythenumberofobservationsusedtocalculatethemeanwageofhighschooldropoutsincityrattimet.
Employmentplacebo
Cardplacebo
Syntheticplacebo
Employmentplacebo Card
placebo
Syntheticplacebo
47
Figure10.Distributionofhypotheticalshort-runimpactsrelativetosyntheticplacebo,assumingasupplyshockhitseachcity-yearpermutation
A. Log wage of high school dropouts
March CPS CPS-ORG
B. Log wage of high school graduates
March CPS CPS-ORG
Notes:Eachyearbetween1980and1995isassumedtobeapotentialtreatmentyear.Thepre-treatmentperiodlasts3years;thepost-treatmentperiodlasts6years.Thewageeffectisestimatedfromadifference-in-differencesregressionmodelthatexcludestheyearofthetreatment.ThefrequencydistributionsdonotincludeanyofthewageeffectsestimatedintheMiamimetropolitanarea.
Mariel Mariel
MarielMariel
48
Figure11.Effectofhypotheticalsupplyshockin1980onlogwageofhighschooldropoutsineachmetropolitanarea,relativetosyntheticplacebo
A.MarchCPS
B.CPS-ORG
Notes:Theexercisetracesthewageeffectofasupplyshockintreatmentyear1980ineachofthe44metropolitanareas.Thewageeffectisdefinedasthedifference-in-differencesΔwrt-Δwr0,whereΔwrtgivesthelogwagegapbetweencityranditssyntheticplaceboattimet;andΔwr0givestheequivalentaveragelogwagegapinpre-treatmentyears1977-1979.Beginningin1980,theillustratedwageeffectsrepresenta3-yearmovingaverage.
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1976 1978 1980 1982 1984 1986 1988 1990 1992
Es#m
ated
logwageeff
ect
Year
Miami
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
1976 1978 1980 1982 1984 1986 1988 1990 1992
Es#m
ated
logwageeff
ect
Year
Miami
49
Table1.EducationdistributionofadultMarielitos
Yearsofeducation Sample: <12 12 13-15 ≥16 SamplesizeMarielitos: April1983CPS 57.9 25.6 3.5 13.1 31 June1986CPS 55.2 28.0 6.4 9.6 31 June1988CPS 58.7 26.1 4.4 10.9 46 1990Census 64.8 15.8 12.9 6.5 4,234 1994CPS-ORG 61.4 20.5 9.8 8.3 143 2000Census 59.9 20.0 12.7 7.4 3,301
Miami’s pre-existing labor force:
1980 Census 26.7 28.4 26.0 18.8 32,971 Notes:ThestatisticsarecalculatedinthesampleofpersonsborninCubawhomigratedtotheUnitedStatesatthetimeofMarielandwere18yearsoldin1980.IntheApril1983CPSand2000census,theMarielitosareidentifiedaspersonsborninCubawhomigratedtotheUnitedStatesin1980.Inallothersamples,theMarielitosareidentifiedasCubanswhoenteredthecountryin1980or1981.Thepre-existinglaborforceofMiamiincludesbothnativesandimmigrants.
50
Table2.ThesizeoftheMarielsupplyshock Education group:
Size of Miami’s labor force in 1980 (1000s)
Number of Marielitos in labor
force (1000s)
Percent increase in supply
High school dropouts 176.3 32.5 18.4 High school graduates 187.5 10.1 5.4 Some college 171.5 8.8 5.1 College graduates 124.1 4.2 3.4
All workers 659.4 55.7 8.4 Notes:Thepre-existingnumberofnativeworkersinMiamiiscalculatedfromthe1980census;thenumberofMarielitoworkers(atleast18yearsoldatthetimeofMariel)iscalculatedfromthe1990census,andasmalladjustmentismadebecausethe1990censusreportsthenumberofCubanimmigrantswhoenteredthecountryin1980or1981.
51
Table3.RatesofemploymentandwagegrowthbeforeMariel
Rank MetropolitanareaEmployment
growth:allworkersEmploymentgrowth:highschooldropouts
Wagegrowth:highschooldropouts
1 SanDiego,CA 0.194 0.067 -0.0932 Greensboro-WinstonSalem,NC 0.182 -0.063 -0.3073 KansasCity,MO/KS 0.179 0.052 -0.1914 Anaheim-SantaAna-GardenGrove,CA 0.162 0.257 0.0675 Rochester,NY 0.153 -0.172 0.0656 Miami-Hialeah,FL 0.153 0.086 0.0147 Nassau-Suffolk,NY 0.151 0.056 -0.0578 SanJose,CA 0.137 0.130 0.1249 Albany-Schenectady-Troy,NY 0.130 0.065 0.05810 Boston,MA 0.121 -0.100 -0.00811 Milwaukee,WI 0.121 -0.006 0.04012 Indianapolis,IN 0.115 0.071 -0.03213 Seattle-Everett,WA 0.110 -0.079 -0.05114 Norfolk-VirginiaBeach-NewportNews,VA 0.103 0.052 0.11115 Philadelphia,PA/NJ 0.102 -0.033 0.00216 Newark,NJ 0.092 -0.116 -0.08917 Tampa-St.Petersburg-Clearwater,FL 0.083 0.068 0.12918 Denver-Boulder-Longmont,CO 0.082 -0.139 -0.01219 Houston-Brazoria,TX 0.078 0.090 0.00420 Sacramento,CA 0.078 0.152 -0.00421 Dallas-FortWorth,TX 0.076 0.062 -0.03722 Portland-Vancouver,OR/WA 0.071 -0.074 -0.01523 Riverside-SanBernardino,CA 0.071 -0.017 0.29824 Atlanta,GA 0.069 -0.087 -0.06225 Cincinnati-Hamilton,OH/KY/IN 0.063 0.038 -0.06826 Washington,DC/MD/VA 0.061 0.028 0.08227 Detroit,MI 0.060 -0.099 -0.01028 FortWorth-Arlington,TX 0.058 -0.006 -0.03329 LosAngeles-LongBeach,CA 0.056 0.075 -0.11230 Columbus,OH 0.048 -0.324 -0.01631 Buffalo-NiagaraFalls,NY 0.039 0.040 -0.14332 Chicago-Gary-LakeIL 0.025 -0.082 -0.01733 St.Louis,MO/IL 0.019 -0.060 -0.02334 Bergen-Passaic,NJ 0.015 -0.051 0.01135 Baltimore,MD 0.012 -0.108 -0.01636 Minneapolis-St.Paul,MN 0.007 -0.050 -0.01037 Cleveland,OH 0.001 -0.071 -0.01738 NewYork,NY 0.000 -0.146 0.06939 Pittsburg,PA -0.013 -0.111 0.12740 Birmingham,AL -0.020 -0.172 -0.09041 SanFrancisco-Oakland-Vallejo,CA -0.027 -0.200 -0.10242 Gary-Hammond-EastChicago,IN -0.029 0.119 0.04243 NewOrleans,LA -0.046 -0.313 -0.03844 Akron,OH -0.110 -0.351 -0.004Notes:Therateofemploymentgrowthisthelogratioofaverageemploymentin1979-1980toaverageemploymentin1977-1978,calculatedusingtheMarchCPSfromthe1977-1980surveyyears.Therateofwagegrowthisthedifferenceinthe(age-adjusted)logweeklywagebetween1978-1979and1976-1977.
52
Table4.Distributionofwagechangeswithinmetroareasacrossallpotentialcity-yearpermutations,1976-2003
Dependent variable: Log wage of education group Characteristics of distribution: < 12 years 12 years 13-15 years ≥ 16 years Value for Mariel -0.439 -0.025 -0.116 -0.062 Distribution across all city-year permutations
Mean of distribution outside Miami -0.100 -0.061 -0.024 0.006 Percentile of Mariel effect 1.8 65.6 19.0 20.7
Distribution in treatment year 1980:
Mean of distribution outside Miami -0.170 -0.152 -0.092 -0.043 Ranking of Mariel effect 1/44 42/44 14/44 17/44 Notes:Thesummarystatisticsarecalculatedfromthedistributionofwagechangesbetweenthepre-andpost-periodforallmetropolitanareas(excludingMiami)forallpossiblepermutationsinthe1976-2003MarchCPSdata.Thepre-treatmentperiodlasts4years;thepost-treatmentperiodlasts6years;andtheyearofthetreatmentisexcludedfromthecalculation.Thedistributionshave774observations.
53
Table5.Difference-in-differencesimpactoftheMarielitosonthewageofhighschooldropouts,MarchCPS
Dependent variable and treatment period
Card placebo
Employment placebo
Synthetic placebo
All cities
A. Log wage of high school dropouts 1981-1983 -0.137 -0.289 -0.210 -0.135 (0.093) (0.090) (0.086) (0.080) 1984-1986 -0.364 -0.495 -0.461 -0.378 (0.080) (0.071) (0.077) (0.033) 1987-1989 -0.216 -0.251 -0.210 -0.192 (0.085) (0.071) (0.068) (0.058) 1990-1992 0.188 0.096 0.021 0.188
(0.158) (0.136) (0.096) (0.111) B. Log wage relative to college graduates
1981-1983 -0.168 -0.390 -0.269 -0.180 (0.187) (0.164) (0.193) (0.170) 1984-1986 -0.387 -0.593 -0.552 -0.453 (0.159) (0.154) (0.193) (0.135) 1987-1989 -0.340 -0.482 -0.387 -0.357 (0.154) (0.159) (0.195) (0.132) 1990-1992 0.180 0.084 0.191 0.192 (0.223) (0.200) (0.141) (0.180)
C. Log wage relative to high school graduates
1981-1983 -0.276 -0.420 -0.383 -0.285 (0.131) (0.146) (0.104) (0.136) 1984-1986 -0.490 -0.627 -0.620 -0.470 (0.114) (0.093) (0.097) (0.094) 1987-1989 -0.344 -0.325 -0.298 -0.254 (0.098) (0.071) (0.041) (0.082) 1990-1992 0.067 0.016 -0.102 0.122 (0.195) (0.144) (0.101) (0.143)
Notes:Robuststandarderrorsarereportedinparentheses.Thedataconsistofannualobservationsforeachcitybetween1977and1992(1980excluded).Allregressionsincludevectorsofcityandyearfixedeffects.ThetablereportstheinteractioncoefficientsbetweenadummyvariableindicatingifthemetropolitanareaisMiamiandthetimingofthepost-Marielperiod.TheregressionsthatusetheCardoremploymentplaceboshave75observations;theregressionsthatusethesyntheticplacebohave30observations;andtheregressionsinthelastcolumnhave658observations.TheregressionsinPanelAareweightedbythenumberofobservationssizeusedtocalculatethedependentvariable.TheregressionsinPanelsBandCareweightedby(n1ns)/(n1+ns),wheren1isthenumberofobservationsusedtocalculatethemeanwageofhighschooldropoutsincityrattimet,andnsistherespectivenumberofobservationsusedtocalculatethemeanwageofthemorehighlyeducatedgroup.Theregressionsthatusethesyntheticplaceboarenotweighted.
54
Table6.Difference-in-differencesimpactoftheMarielitosonthewageofhighschooldropouts,CPS-ORG
Dependent variable and treatment period
Card placebo
Employment placebo
Synthetic placebo
All cities
A. Log wage of high school dropouts 1981-1983 -0.068 -0.153 -0.240 -0.092 (0.027) (0.060) (0.082) (0.027) 1984-1986 -0.032 -0.097 -0.203 -0.075 (0.039) (0.066) (0.078) (0.028) 1987-1989 -0.061 -0.206 -0.241 -0.137 (0.031) (0.055) (0.075) (0.018) 1990-1992 0.005 -0.105 -0.182 -0.051
(0.058) (0.078) (0.075) (0.041) B. Log wage relative to college graduates
1981-1983 -0.020 -0.171 -0.302 -0.066 (0.059) (0.114) (0.117) (0.069) 1984-1986 -0.018 -0.130 -0.275 -0.067 (0.056) (0.096) (0.109) (0.057) 1987-1989 -0.048 -0.291 -0.377 -0.152 (0.055) (0.111) (0.112) (0.061) 1990-1992 -0.017 -0.173 -0.283 -0.074 (0.086) (0.127) (0.115) (0.077)
C. Log wage relative to high school graduates
1981-1983 -0.141 -0.188 -0.320 -0.130 (0.033) (0.072) (0.088) (0.041) 1984-1986 -0.084 -0.122 -0.242 -0.092 (0.070) (0.094) (0.096) (0.060) 1987-1989 -0.081 -0.173 -0.222 -0.108 (0.041) (0.061) (0.077) (0.039) 1990-1992 0.023 -0.082 -0.184 -0.033 (0.069) (0.062) (0.076) (0.061)
Notes:Robuststandarderrorsarereportedinparentheses.Thedataconsistofannualobservationsforeachcitybetween1977and1992(1980excluded).Allregressionsincludevectorsofcityandyearfixedeffects.ThetablereportstheinteractioncoefficientsbetweenadummyvariableindicatingifthemetropolitanareaisMiamiandthetimingofthepost-Marielperiod.TheregressionsthatusetheCardoremploymentplaceboshave75observations;theregressionsthatusethesyntheticplacebohave30observations;andtheregressionsinthelastcolumnhave660observations.TheregressionsinPanelAareweightedbythesamplesizeusedtocalculatethedependentvariable.TheregressionsinPanelsBandCareweightedby(n1ns)/(n1+ns),wheren1isthenumberofobservationsusedtocalculatethemeanwageofhighschooldropoutsincityrattimet,andnsistherespectivenumberofobservationsusedtocalculatethemeanwageofthemorehighlyeducatedgroup.Theregressionsthatusethesyntheticplaceboarenotweighted.
55
Table7.Difference-in-differencesshort-runimpactsoftheMarielitos Sample
Card placebo
Employment placebo
Synthetic placebo
All cities
A. Coefficients from March CPS
1. Log wage of high school dropouts -0.237 -0.374 -0.335 -0.237 (0.088) (0.078) (0.090) (0.076) 2. Log wage of “pooled” high school -0.030 -0.064 -0.035 -0.039
dropouts and graduates (0.049) (0.063) (0.082) (0.059) 3. Interquantile range (20th – 80th percentile) -0.062 -0.029 -0.024 -0.044 (0.108) (0.096) (0.098) (0.100) 4. Black/white relative wage -0.107 -0.221 --- -0.092
(0.072) (0.098) (0.061) B. Coefficients from CPS-ORG
1. Log wage of high school dropouts -0.054 -0.130 -0.227 -0.087 (0.026) (0.049) (0.071) (0.022)
2. Log wage of pooled high school -0.003 -0.052 -0.050 -0.036
dropouts and graduates (0.018) (0.019) (0.022) (0.014) 3. Interquantile range (20th – 80th percentile) 0.017 -0.031 -0.063 -0.037 (0.041) (0.051) (0.059) (0.040) 4. Black/white relative wage -0.134 -0.135 -0.110 -0.127
(0.037) (0.051) (0.045) (0.037) Notes:Robuststandarderrorsarereportedinparentheses.Thedataconsistofannualobservationsforeachcitybetween1977and1986(1980excluded).Allregressionsincludevectorsofcityandyearfixedeffects.ThetablereportstheinteractioncoefficientsbetweenadummyvariableindicatingifthemetropolitanareaisMiamiandiftheobservationisdrawnfromthepost-Marielperiod.TheregressionsthatusetheCardoremploymentplaceboshave45observations;theregressionsthatusethesyntheticplacebohave18observations;andtheregressionsinthelastcolumnhave396observations.SeethenotestoTable6foradescriptionoftheweightingusedintheregressions.
56
Table8.Thedistributionofestimatedshort-runwageeffectsonthelogweeklywageofhighschooldropoutsacrossallfour-cityplacebos,1977-1986
Characteristics of distribution: March CPS CPS-ORG Mean -0.243 -0.089 Standard deviation 0.047 0.023 Statistical significance
Fraction of t-statistics above |1.6| 0.984 0.947 Fraction of t-statistics above |2.0| 0.939 0.845
Average employment growth of placebo cities within 0.5 standard deviations of Miami (N = 5,740)
Mean -0.282 -0.105 Fraction of t-statistics above |1.6| 0.998 0.933 Fraction of t-statistics above |2.0| 0.980 0.812
Employment growth for each placebo city within 0.5 standard deviations of Miami (N = 126)
Mean -0.333 -0.098 Fraction of t-statistics above |1.6| 1.000 0.833 Fraction of t-statistics above |2.0| 1.000 0.619
Actual impact using the Card placebo:
Coefficient -0.237 -0.054 Robust standard error (0.088) (0.026)
Actual impact using the employment placebo: Coefficient -0.374 -0.130 Robust standard error (0.078) (0.049)
Actual impact using the synthetic placebo: Coefficient -0.335 -0.227 Robust standard error (0.090) (0.071)
Notes:ThetablereportsthedistributionoftheinteractioncoefficientbetweenadummyvariableindicatingifthemetropolitanareaisMiamiandiftheobservationisdrawnfromthepost-Marielperiod.Theregressionswereestimatedseparatelyinallpossible123,410four-cityplacebos.Theregressionsuseannualobservationsforeachcityfrom1977through1986(excluding1980).Allregressionshave45observationsandareweightedbythesamplesizeusedtocalculatethemeanlogage-adjustedwageofhighschooldropoutsincityrattimet.
57
Table9.Distributionofwageeffectsrelativetothesyntheticplaceboforhypotheticalsupplyshocks
Dependent variable: Log wage of education group Characteristics of distribution: < 12 years 12 years 13-15 years ≥ 16 years A. March CPS Mean effect -0.003 -0.000 -0.006 -0.000 Standard deviation 0.163 0.071 0.099 0.072 Fraction of t-statistics above |1.6| 0.250 0.301 0.262 0.278 Fraction of t-statistics above |2.0| 0.167 0.205 0.185 0.182 Mariel wage impact with synthetic control:
Coefficient -0.335 0.114 -0.042 0.104 Robust standard error (0.090) (0.076) (0.116) (0.086)
Placement of Mariel effect:
Percentile in distribution across all years 3.0 94.8 33.2 93.2 Rank in 1980 treatment year 1/44 44/44 14/43 43/44
B. CPS-ORG Mean effect 0.001 0.000 0.002 -0.002 Standard deviation 0.104 0.049 0.065 0.053 Fraction of t-statistics above |1.6| 0.253 0.306 0.292 0.328 Fraction of t-statistics above |2.0| 0.154 0.218 0.194 0.214 Mariel wage impact with synthetic control:
Coefficient -0.227 0.042 0.071 0.052 Robust standard error (0.072) (0.021) (0.057) (0.061)
Placement of Mariel effect:
Percentile in distribution across all years 1.8 81.6 89.4 84.8 Rank in 1980 treatment year 1/44 37/44 38/44 36/44
Notes:Thepre-treatmentperiodlasts3years;thepost-treatmentperiodlasts6years.Eachregressionexcludestheyearofthetreatmentandhas18observations.Thereare774hypotheticalshocksdistributedacross43metropolitanareas(outsideMiami)fortreatmentyearsbetween1980and1997.Thepredictorsusedtocreatethesyntheticplaceboarethecity’srateoftotalemploymentgrowth,theratesofemploymentandwagegrowthfortheparticulareducationgroupinthe4-yearperiodprecedingthetreatmentyear.
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AppendixTableA-1.Weightsdefiningthesyntheticcontrol
MeasureofwageofhighschooldropoutsRank Metropolitanarea Actuallogweeklywage Age-adjustedlogweeklywage MarchCPS MarchCPS CPS-ORG1 SanDiego,CA 0.015 0.239 0.2342 Greensboro-WinstonSalem,NC 0.000 0.006 0.0003 KansasCity,MO/KS 0.560 0.010 0.0164 Anaheim-SantaAna-GardenGrove,CA 0.203 0.372 0.3965 Rochester,NY 0.004 0.159 0.1646 Miami-Hialeah,FL --- --- ---7 Nassau-Suffolk,NY 0.013 0.011 0.0138 SanJose,CA 0.009 0.043 0.0079 Albany-Schenectady-Troy,NY 0.006 0.012 0.01010 Boston,MA 0.005 0.008 0.01011 Milwaukee,WI 0.005 0.009 0.01012 Indianapolis,IN 0.008 0.007 0.00713 Seattle-Everett,WA 0.005 0.006 0.00814 Norfolk-VirginiaBeach-NewportNews,VA 0.005 0.008 0.00715 Philadelphia,PA/NJ 0.005 0.006 0.00816 Newark,NJ 0.004 0.005 0.00617 Tampa-St.Petersburg-Clearwater,FL 0.005 0.006 0.00618 Denver-Boulder-Longmont,CO 0.004 0.005 0.00619 Houston-Brazoria,TX 0.007 0.005 0.00520 Sacramento,CA 0.041 0.005 0.00221 Dallas-FortWorth,TX 0.007 0.005 0.00522 Portland-Vancouver,OR/WA 0.004 0.005 0.00523 Riverside-SanBernardino,CA 0.002 0.000 0.00724 Atlanta,GA 0.004 0.004 0.00525 Cincinnati-Hamilton,OH/KY/IN 0.007 0.004 0.00526 Washington,DC/MD/VA 0.005 0.004 0.00527 Detroit,MI 0.004 0.004 0.00528 FortWorth-Arlington,TX 0.005 0.004 0.00529 LosAngeles-LongBeach,CA 0.007 0.004 0.00430 Columbus,OH 0.002 0.004 0.00331 Buffalo-NiagaraFalls,NY 0.006 0.003 0.00432 Chicago-Gary-LakeIL 0.004 0.003 0.00433 St.Louis,MO/IL 0.004 0.003 0.00334 Bergen-Passaic,NJ 0.003 0.003 0.00335 Baltimore,MD 0.004 0.003 0.00336 Minneapolis-St.Paul,MN 0.004 0.003 0.00337 Cleveland,OH 0.003 0.003 0.00338 NewYork,NY 0.003 0.003 0.00339 Pittsburg,PA 0.002 0.003 0.00340 Birmingham,AL 0.003 0.002 0.00241 SanFrancisco-Oakland-Vallejo,CA 0.003 0.002 0.00242 Gary-Hammond-EastChicago,IN 0.004 0.002 0.00243 NewOrleans,LA 0.002 0.002 0.00144 Akron,OH 0.001 0.001 0.001Notes:Themetropolitanareasarerankedbythe1977-1980rateofemploymentgrowth.