I: NLSY79 I.A. NLSY79 Variables
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Page 1 of 22 DATA APPENDIX SMART AND ILLICIT: WHO BECOMES AN ENTREPRENEUR AND DO THEY EARN MORE? ROSS LEVINE AND YONA RUBINSTEIN July 2016 I: NLSY79 I.A. NLSY79 Variables Earnings: Annual Hours Worked NUMBER OF HOURS WORKED IN PAST CALENDAR YEAR R24456.00 Full-time, Full- Year If the respondent (1) works 50 or more weeks per year and (2) works 2000 or more hours per year, and (3) works 40 or more hours per week, then Full-time, Full-year is set equal to one, otherwise it is set equal to zero. Earnings Wages plus income from business. Deflated by the CPI corresponding to when those earnings were realized. Earnings are in 2010 prices. Demographics and Family: Age The age of the respondent. Current year – year of birth. College Graduate (or more) Graduated from college or obtained an advanced degree. Educational attainment (six categories) The six educational attainment categories: (i) high school dropouts: less than 12 years of schooling (ii) GED degree (iii) high school graduates: 12 years of schooling (iv) had some college education: 13-15 years of schooling (i) college education: 16 years of schooling (vi) advanced studies: 17+ years of schooling. These are measured at the end of the respondent’s educational experience, so that they do not vary over time for a respondent. Family Income in 1979 The income of the respondent’s family in 1979 in 2010-year prices. In those cases where 1979 is missing, we use the earliest year between 1980 and 1981 with a non-missing value. See section I.E. NLSY79 Family Income in 1979 for details. Father's Education Years of schooling of the respondent's father. See Section I.D. NLSY79 Imputation of Mother and Father Education for details. Female Equals one if the respondent reports being female and zero otherwise. Mother's Education Years of schooling of the respondent's mother. See Section I.D. NLSY79 Imputation of Mother and Father Education for details. Potential experience Equals the age of the respondent minus the years of schooling minus six, or, if this computation is less than zero, then potential experience set equal to zero.
Transcript of I: NLSY79 I.A. NLSY79 Variables
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DATAAPPENDIX
SMARTANDILLICIT:WHOBECOMESANENTREPRENEURANDDOTHEYEARNMORE?
ROSSLEVINEANDYONARUBINSTEIN
July2016
I:NLSY79
I.A.NLSY79Variables
Earnings: AnnualHoursWorked
NUMBEROFHOURSWORKEDINPASTCALENDARYEARR24456.00
Full-time,Full-Year
Iftherespondent(1)works50ormoreweeksperyearand(2)works2000ormorehoursperyear,and(3)works40ormorehoursperweek,thenFull-time,Full-yearissetequaltoone,otherwiseitissetequaltozero.
Earnings Wagesplusincomefrombusiness.DeflatedbytheCPIcorrespondingtowhenthoseearningswererealized.Earningsarein2010prices.
DemographicsandFamily:
Age Theageoftherespondent.Currentyear–yearofbirth.CollegeGraduate(ormore)
Graduatedfromcollegeorobtainedanadvanceddegree.
Educationalattainment(sixcategories)
Thesixeducationalattainmentcategories:(i)highschooldropouts:lessthan12yearsofschooling(ii)GEDdegree(iii)highschoolgraduates:12yearsofschooling(iv)hadsomecollegeeducation:13-15yearsofschooling(i)collegeeducation:16yearsofschooling(vi)advancedstudies:17+yearsofschooling.Thesearemeasuredattheendoftherespondent’seducationalexperience,sothattheydonotvaryovertimeforarespondent.
FamilyIncomein1979
Theincomeoftherespondent’sfamilyin1979in2010-yearprices.Inthosecaseswhere1979ismissing,weusetheearliestyearbetween1980and1981withanon-missingvalue.SeesectionI.E.NLSY79FamilyIncomein1979fordetails.
Father'sEducation
Yearsofschoolingoftherespondent'sfather.SeeSectionI.D.NLSY79ImputationofMotherandFatherEducationfordetails.
Female Equalsoneiftherespondentreportsbeingfemaleandzerootherwise.
Mother'sEducation
Yearsofschoolingoftherespondent'smother.SeeSectionI.D.NLSY79ImputationofMotherandFatherEducationfordetails.
Potentialexperience
Equalstheageoftherespondentminustheyearsofschoolingminussix,or,ifthiscomputationislessthanzero,thenpotentialexperiencesetequaltozero.
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Twoparentfamily(14)
Equalsoneiftherespondentlivedinatwo-parentfamilyattheageof14.
White Equalsoneiftherespondentreportsbeingwhiteandzerootherwise.
Yearofbirth Thecalendaryearinwhichtherespondentwasborn.YearsofSchooling
Therespondent’smaximumnumberofyearsofschooling,soitdoesnotvaryovertimeforarespondent
Traits,etc. AFQT ArmedForcesQualificationsTestscoremeasurestheaptitudeand
trainabilityoftherespondent.Collectedduringthe1980NLSY79survey,theAFQTscoreisbasedonarithmeticreasoning,worldknowledge,paragraphcomprehension,andnumericaloperations.Itisfrequentlyemployedasageneralindicatorofcognitiveskills.ThisAFQTscoreismeasuredasapercentileoftheNLSY79survey,withamedianvalueof50.
AppliedforPatent(residualstandardized)
WesetAppliedforPatentequaloneiftherespondentin2010answered,"yes"tothequestion,"Hasanyone,includingyourself,everappliedforapatentforworkthatyousignificantlycontributedto?"SinceAppliedforPatentisobtaineddecadesafterapersonbecomesprimeage,wecollecttheresidualsfromaregressionofAppliedforPatentoneducation,AFQT,RosenbergSelf-Esteem,RotterLocusofControl,theIllicitIndex,andyearofbirth.WethenstandardizetheseresidualstoobtainAppliedforPatent(residualstandardized),whichhasameanofzeroandastandarddeviationofone.
Entrepreneur(residualstandardized)
WesetthevariableEntrepreneurequalsoneiftherespondentin2010answers,"yes"tothequestion,"Doyouconsideryourselftobeanentrepreneur?”Inposingthequestion,theNLSY79definesanentrepreneuras“someonewholaunchesabusinessenterprise,usuallywithconsiderableinitiativeandrisk."SinceEntrepreneurisobtaineddecadesafterapersonbecomesprimeage,wecollecttheresidualsfromaregressionofEntrepreneuroneducation,AFQT,RosenbergSelf-Esteem,RotterLocusofControl,theIllicitIndex,andyearofbirth.WethenstandardizetheseresidualstoobtainEntrepreneur(residualstandardized),whichhasameanofzeroandastandarddeviationofone.
Force(raw) Thisequalsoneiftherespondentreportsinthe1980surveyeverusingforcetoobtainsomething.
IllicitActivityIndex(standardized)
Thisisconstructedbasedontheanswersto20questionsinthe1980survey,where17arequestionsabout"delinquency"and3areaboutruninswiththe"police."Thedelinquencyquestionscoverissuesassociatedwithdamagingproperty,fightingatschool,shoplifting,robbery,usingforcetoobtainthings,assault,threateningtoassaultsomebody,druguse,dealingdrugs,gambling,etc.The"police"questionsinvolvebeingstoppedbythepolicy,chargedwithanillegalactivity,orconvicted,allforactivitiesother
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thanminortrafficoffenses.Foreachquestion,weassignthevalueoneifthepersonengagedinthatactivityandzerootherwise.Foreachrespondent,wethenaddthesevaluesanddivideby20.Wethenstandardizethevaluesbysubtractingthesamplemeananddividingbythestandarddeviation,sothattheIllicitActivityIndexhasameanofzeroandastandarddeviationofone.WeprovideamoredetailedexplanationinSectionI.B.NLSY79IllicitActivityIndex.
RosenbergSelf-Esteem(standardized)
RosenbergSelf-Esteemscoreisbasedonaten-partquestionnairegiventoallNLSY79participantsin1980.Itmeasuresthedegreeofapprovalordisapprovalofone’sself.Thevaluesrangefromsixto30,wherehighervaluessignifygreaterself-approval.RosenbergSelf-Esteem(standardized)standardizesthescore,sothatithasameanofzeroandastandarddeviationofone.
RotterLocusofControl(standardized)
RotterLocusofControlmeasuresthedegreetowhichrespondentsbelievetheyhaveinternalcontroloftheirlivesthroughself-determinationrelativetothedegreethatexternalfactors,suchaschance,fate,andluck,shapetheirlives.Itwascollectedaspartofapsychometrictestinthe1979NLSY79survey.TheRotterLocusofControlrangesfrom4to16,wherehighervaluessignifylessinternalcontrolandmoreexternalcontrol.Thisisstandardized,sothatithasameanofzeroandastandarddeviationofone.
Steal50orless(raw)
Thisequalsoneiftherespondentreportsinthe1980surveystealingsomethingworth$50orlessduringtheyear.
StoppedbyPolice(raw)
Thisequalsoneiftherespondentreportsinthe1980surveyeverbeingstoppedbythepolice.
Employmenttype
Salaried FromtheNLSY79’sunifiedclassofworker(R24455.10),therearefourresponsesforworkingrespondents:(1)Privatecompany,includingnon-profit,(2)government,(3)self-employed,and(4)thoseworkingwithoutpay,includinginfamilybusinesses.WesetSalariedequaltooneiftherespondent’sclassofworkeriseither“(1)”or“(2)”andzerootherwise.
Self-employed FromtheNLSY79’sunifiedclassofworker(R24455.10),therearefourresponsesforworkingrespondents:(1)Privatecompany,includingnon-profit,(2)government,(3)self-employed,and(4)thoseworkingwithoutpay,includinginfamilybusinesses.WesetSelf-employedequaltooneiftherespondent’sclassofworkeris“(3)”andzerootherwise.
IncorporatedSelf-employed
Ifarespondentisself-employed,theNLSY79furtheraskswhetherthebusinessisincorporatedornot.Iftherespondentisself-employedandthebusinessisincorporated,thenIncorporatedSelf-employedequalsoneanditiszerootherwise.SeeSectionI.C.NLSY79IncorporatedSelf-EmploymentCodingDetails.
UnincorporatedSelf-employed
Ifarespondentisself-employed,theNLSY79furtheraskswhetherthebusinessisincorporatedornot.Iftherespondentisself-
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employedandthebusinessisunincorporated,thenUnincorporatedSelf-employedequalsoneanditiszerootherwise.
I.B.NLSY79IllicitActivityIndex
Inthissubsection,wefirstdescribethecoredatafromtheNLSY79surveyandthenprovidedetailsontheconstructionoftheindex
I.B.1.TheCoreData
TheIllicitActivityindexisbasedonquestionsfromthe1980survey.Weusetwotypesofquestionsonillicitactivities“delinquency”and“police”questions.
Weusedataon17ofthe20questionson“delinquency”providedbytheNLSY79.Wedonotusetheotherthreequestionsthatwereonlyposedtopeoplewhowere17yearsoldoryoungerin1979.Thus,thesequestionswereonlyaskedofabout30%ofthesample(3,898outof12,686).Includingthesevariableswouldreducethesamplebyabout70%.Thesurveyasksaboutwhether—andhowmanytimes—therespondentengagedinthedelinquentact.Forexample,oneofthequestionsaskshowmanytimestherespondentsmokedmarijuana/hashishinthepastyear.Welistall20questionsbelowandindicatewhichonesweuseinconstructingtheIllicitActivityIndex.(Thisistitled“Tableonthedistributionofresponsestoquestionsondelinquencyandpolice.”)
Usetwoversionsoftheresponsestothedelinquencyquestions:
(1)Thereisthe“0-6intensive”versionthatusestheactualnumberoftimestherespondentengagedinthedelinquentact,wheretherearesevenanswerscategorizedfromzerotosix;and
(2)Thereisourprimary,core(“extensive”)versionthatusesthevaluesofzerooroneincodingtheresponsestothedelinquencyquestions,i.e.,wecodethevaluesaseitherthepersondidordidnotengageintheactatleastonce.
Withrespecttothe“police”questions,weusethethreequestionsoninteractionswiththepoliceprovidedbytheNLSY79.Thesethreequestionsofferzero/oneoptionsforresponses.Forexample,oneofthequestionsasks,wereyou“…everconvictedonillegalactivitychargesotherthanminortrafficoffense?”Welistthesequestionsbelowalso.
Hereisalistingofthecoredata:
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NLSY79ReferenceNumber
QuestionName Definition
Yearofsurvey Sample
DelinquencyquestionsusedinconstructingtheIllicitActivityIndex
R03049.00 DELIN-4
ILLEGAL ACTIVITY 80 INT - TIMES INTENTIONALLY DAMAGED PROPERTY IN PAST YEAR 1980 ALL
R03050.00 DELIN-5ILLEGAL ACTIVITY 80 INT - TIMES FOUGHT AT SCHOOL OR WORK IN PAST YEAR 1980 ALL
R03051.00 DELIN-6
ILLEGAL ACTIVITY 80 INT - TIMES SHOPLIFTED IN PAST YEAR 1980 ALL
R03052.00 DELIN-7
ILLEGAL ACTIVITY 80 INT - TIMES STOLEN OTHER'S BELONGINGS PAST YR (WORTH <$50) 1980 ALL
R03053.00 DELIN-8
ILLEGAL ACTIVITY 80 INT - TIMES STOLEN OTHER'S BELONGINGS PAST YR (WORTH >$50) 1980 ALL
R03054.00 DELIN-9
ILLEGAL ACTIVITY 80 INT - TIMES USED FORCE TO OBTAIN THINGS IN PAST YEAR 1980 ALL
R03055.00
DELIN-10
ILLEGAL ACTIVITY - TIMES SERIOUSLY THREATENED TO HIT/HIT SOMEONE PAST YEAR 1980 ALL
R03056.00
DELIN-11
ILLEGAL ACTIVITY 80 INT - TIMES ATTACKED W/INTENT TO INJURE/KILL IN PAST YEAR 1980 ALL
R03057.00
DELIN-12
ILLEGAL ACTIVITY 80 INT - TIMES SMOKED MARIJUANA/HASHISH IN PAST YEAR 1980 ALL
R03058.00
DELIN-13
ILLEGAL ACTIVITY - TIMES USED OTHER DRUGS/CHEMICALS TO GET HIGH IN PAST YEAR 1980 ALL
R03059.00
DELIN-14
ILLEGAL ACTIVITY 80 INT - TIMES SOLD MARIJUANA/HASHISH IN PAST YEAR 1980 ALL
R03060.00
DELIN-15
ILLEGAL ACTIVITY 80 INT - TIMES SOLD HARD DRUGS IN PAST YEAR 1980 ALL
R03061.00
DELIN-16
ILLEGAL ACTIVITY 80 INT - TIMES ATTEMPTED TO "CON" SOMEONE IN PAST YEAR 1980 ALL
R03062.00
DELIN-17
ILLEGAL ACTIVITY 80 INT - TIMES TAKEN AUTO W/OUT OWNER PERMISSION IN PAST YEAR 1980 ALL
R03063.00
DELIN-18
ILLEGAL ACTIVITY 80 INT - TIMES BROKEN INTO A BUILDING IN PAST YEAR 1980 ALL
R03064.00
DELIN-19
ILLEGAL ACTIVITY 80 INT - TIMES KNOWINGLY SOLD/HELD STOLEN GOODS IN PAST YEAR 1980 ALL
R03065.00
DELIN-20
ILLEGAL ACTIVITY 80 INT - TIMES AIDED IN GAMBLING OPERATION IN PAST YEAR 1980 ALL
Policequestions(zero/oneanswers)
R03067.00 POLICE-1
EVER "STOPPED" BY POLICE FOR OTHER THAN MINOR TRAFFIC OFFENSE? 1980 ALL
R03071.00 POLICE-2
EVER CHARGED WITH ILLEGAL ACTIVITY? 80 INT (EXC MINOR TRAFFIC OFFENSE) 1980 ALL
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R03078.00 POLICE-3
EVER CONVICTED ON ILLEGAL ACTIVITY CHARGES OTHER THAN MINOR TRAFFIC OFFENSE? 1980 ALL
DelinquencyquestionsNOTusedinconstructingtheIllicitActivityIndexNLSY79ReferenceNumber
QuestionName Definition
Yearofsurvey Sample
R03046.00 DELIN-1ILLEGAL ACTIVITY 80 INT - TIMES RUN AWAY FROM HOME IN PAST YR (AGE 17 OR UNDER) 1980 R<=17
R03047.00 DELIN-2ILLEGAL ACTIVITY 80 INT - TIMES SKIPPED SCHOOL DAY IN PAST YR (AGE 17 OR UNDER) 1980 R<=17
R03048.00 DELIN-3ILLEGAL ACTIVITY - TIMES DRANK ALCOHOLIC BEVERAGES PAST YR (AGE 17 OR UNDER) 1980 R<=17
Theselastthreequestionsareexcludedbecausetheywereonlyaskedofrespondentswhowere17yearsoryoungerin1979(bornbetween1962and1964).Includingthemwouldreducethesampleby70%.
I.B.2.ConstructingtheIndex
TheIllicitIndex
1. Sample:ofthe12,686individualsintheNLSY79survey,1,310havemissingdataononeofthe17delinquencyquestionsthatweincludeinourIndex.Oftheremaining11,376individuals,19havemissingdataononeofthethreepolicequestions.
Thisistabulatedasfollows:
Variable/SelectionCriteria Persons Dropped
Initialnumberofpersons 12,686 0Missingoneofthe17questions 11,376 1,310Missingoneofthe3questions 11,357 19
FinalNumberofPerson-Observations 11,357
2. Weusethe(i)responsestothethreepolicequestions(whichofferzero/oneresponsesintheNLSY79survey)and(ii)the“one/zero”responsestothe17delinquencyquestions,i.e.,weusetheextensiveversionsoftheanswerstothedelinquencyquestions.
3. Foreachrespondent,wesumtheresponsestothetwentyzero/oneresponsesanddivideby20.Wethenstandardizethevaluesbysubtractingthesamplemeananddividingbythestandarddeviation,sothattheIllicitActivityIndexhasameanofzeroandastandarddeviationofone.
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TheIllicitActivityIndex0-6Intensive
1. Weusethefullanswerstothe17delinquencyvariablesconcerningthenumberoftimestherespondentengagedintheactivity.Specifically,therearesevenpossibleanswers:(0)never,(1)once,(2)twice,(3)3-5times,(4)6-10times,(5)11-50times,and(6)morethan50times.
2. FortheIllicitActivityIndex0-6Intensive,weassignthevalues0,1,2,4,8,30,and50tothesevenanswers.
3. Wethen(a)computethestandardizedvalueofeachofthe20questions((value–mean)/standarddeviation))andthen(b)sumthevaluesanddivideby20.
Thetwo,IllicitActivityIndex(standardized)andtheIllicitActivityIndex0-6intensive(standardized),areveryhighlycorrelated(0.91)andthepaper’sresultsholdwhenusingeitherIndex.WeillustratethisrobustnessintheAppendixTables:APPENDIXTABLEVIIA,APPENDIXTABLEVIII,andAPPENDIXTABLEXI.
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TheDistributionofResponsestoQuestionsonDelinquencyandPolice:
Question N Min Median Mean Max NEVER ONCE TWICE TIMES_3_5 TIMES_1_10 TIMES_11_50 TIMES_50P
DelinquencyquestionsusedinconstructingtheIllicitActivityIndexDAMAGED 11734 0 0 0.36 6 0.82 0.09 0.04 0.04 0.01 0.00 0.00FOUGHT 11800 0 0 0.56 6 0.72 0.13 0.06 0.06 0.02 0.01 0.00SHOPLIFTED 11788 0 0 0.53 6 0.74 0.12 0.05 0.05 0.02 0.01 0.00STEEL50M 11788 0 0 0.37 6 0.81 0.09 0.04 0.04 0.01 0.01 0.00STEEL50P 11776 0 0 0.11 6 0.94 0.03 0.01 0.01 0.00 0.00 0.00FORCE 11794 0 0 0.10 6 0.95 0.03 0.01 0.01 0.00 0.00 0.00THREAT 11785 0 0 0.82 6 0.63 0.16 0.08 0.08 0.03 0.02 0.01ATTACK 11792 0 0 0.20 6 0.89 0.06 0.02 0.02 0.01 0.00 0.00MARIJUANA 11722 0 0 1.84 6 0.53 0.09 0.04 0.07 0.05 0.07 0.15DRUGES 11698 0 0 0.60 6 0.81 0.05 0.03 0.04 0.03 0.03 0.02MARIJUANA_SOLD 11693 0 0 0.33 6 0.89 0.03 0.02 0.02 0.02 0.01 0.01DRUGES_SOLD 11717 0 0 0.07 6 0.97 0.01 0.00 0.00 0.00 0.00 0.00CON 11721 0 0 0.48 6 0.78 0.09 0.05 0.05 0.02 0.01 0.01AUTO 11752 0 0 0.14 6 0.92 0.04 0.01 0.01 0.00 0.00 0.00BROKEN 11748 0 0 0.12 6 0.94 0.03 0.01 0.01 0.00 0.00 0.00SOLD 11749 0 0 0.23 6 0.89 0.06 0.02 0.02 0.01 0.00 0.00GAMBELING 11737 0 0 0.06 6 0.98 0.01 0.00 0.00 0.00 0.00 0.00
Policequestions(zero/oneanswers)usedinconstructingtheIllicitActivityIndexSTOPPED_POLICE 12129 0 0 0.19 1 0.81 0.19 0.00 0.00 0.00 0.00 0.00CHARGED 12136 0 0 0.11 1 0.89 0.11 0.00 0.00 0.00 0.00 0.00CONVICTED 12130 0 0 0.06 1 0.94 0.06 0.00 0.00 0.00 0.00 0.00
AVG 0.84 0.07 0.03 0.03 0.01 0.01 0.01
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I.C.NLSY79IncorporatedSelf-employmentCodingDetails
Wefollowthefollowingprocessforcodingincorporatedself-employment.
1.TheNLSY79providesinformationon(a)theclassofworker,includingwhethertherespondent(R)issalariedorself-employed,and(b)whetherR’sbusinessisincorporated.
2.From1994onward,theNLSY79notesthatwheneverR’sjobisthesameasthejobinthelastinterview,classofworkerandincorporationstatusareonlyreportediftheinformationhaschanged.Itiscodedasmissingiftherehasbeennochangesincethelastinterview.
3.Forexample,ifpersonAhasbeencontinuouslyself-employedby"ALConsulting,Inc."forseveralyears,A’s"raw"datamightlooklikethis:
YearCOW(job#1)INCORP(job#1)20004(SE)1(yes)2002-4-42004-4-42006-4-42008-4-42010-4-4Eventhoughjob#1referstothesamejob(ALConsulting,Inc.)ineachoftheseinterviews,COWandINCORParemissingafterthefirstyearbecausetheyarenotre-asked.4. TheNLSY79solvesthisproblemforclassofworker.Theyappropriately“fillin”the
informationonclassofworkerforeachRratherthanleavingdataentriesas“missing,”e.g.,seetheclassofworkervariableforJob#1intheNLSY79Navigator).TheCOWALLvariables(e.g.,R4587905=COWALL-EMP1_1994,whichisCOWforjob#1in1994)havebeen"filledin"tocarrytheoldinformationforward.
5. TheNLSY79,however,didnot“fillin”theincorporationstatus.TheINCORPvariables(e.g.,R4587000=QES1-56E_1994,whichisINCORPforjob#1in1994)havenot.Soifoneispairing(created)COWALLvariableswith(raw)INCORPvariables,the(fake)datawilllooklikethis:
YearCOWALL-EMP1INCORP(job#1)20004(SE)1(yes)20024-420044-420064-420084-420104-4Clearly,therearemanycaseswhereINCORPismissingeventhoughCOWALL=SE.6. Thereisastraightforwardprocedureforaddressingthiscodingissue.IfRisself-employed,
usetheincorporationstatusofthelastinterviewtoappropriately“fillin”missingvalues(i.e.,fillinthe“validskips”).Afterfollowingthisprocedure,incorporatestatushas1.5%missingvaluesbasedonthesampleofindividualsintheTableIsummarystatistics.
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7. WemakeafewadditionaladjustmentsforRswho(a)areself-employedbut(b)havemissingvaluesofincorporatedbusinessstatusafterfollowingtheaboveprocedureinasurveyyear.
7.a.Wefind3person-yearobservationsafter1994whereRisself-employedandRreportshavingthesamejobaslastyearandRwasincorporatedlastyear.WecodeRasincorporated.(SameJobasLastYear)7.b.Wefind8person-yearobservations(after1994)inwhichtheNLSY79indicatesinsurveyt+1that(a)Risincorporatedand(b)hasthesamejobaslastyear,sowecodeRasincorporatedinsurveyt.(SameJobasNextYear)7.c.Wefind7person-yearobservationspriorto1994inwhichaself-employedpersoninperiodtandt-1hasamissingvalueforincorporatedstatusinsurveyt,andwasincorporatedself-employedinsurveyt-1.WecodetheseRsasincorporatedinsurveyt.(Pre-1994:SameJobasLastYear)
7.d.Wefind9person-yearobservationsinwhichaself-employedpersoninsurveytandt+1hasamissingvalueforincorporatedstatusinsurveytbutisincorporatedself-employedinsurveyt+1.WecodetheseRsasincorporatedinsurveyt.(Pre-1994:SameJobasNextYear)
7.e.Afterthis,thereare2additionalperson-yearobservationsinwhichtheincorporatedstatusismissing,butinwhichoneofRsotherjobs,i.e.,Job2–Job5,isincorporated.Wecodethesetwoobservationsasincorporated.AcrossJobCategories)
7.f.Theresultsarerobusttokeepingthese29person-yearobservationsasmissing,asshowninAppendixTables.SeeAPPENDIXTABLEI,APPENDIXTABLEII,APPENDIXTABLEIV,andAPPENDIXTABLEVIIB.
Specifically,fromtheSTATAprogramforthe1,936person-yearobservationscodedasincorporatedself-employed,wetabulatethefollowing:
IncorporatedSource Freq. % Cum. NLSY79rawdata 1,501 77.53 77.53NLSY79post1994procedure 4,06 20.97 98.50SamejobaslastYear 3 0.15 98.66Samejobasnextyear 8 0.41 99.07Pre-1994:samejobaslastyear 7 0.36 99.43Pre-1994:samejobasnextyear 9 0.46 99.90Acrossjobcategories 2 0.10 100.0
I.D.NLSY79:ImputationofMotherandFatherEducation
Ofthe132,681person-yearobservation(10,719individuals)coveredinTableI,125,291(10,093)havemother’seducationand115,216(9,263)havefather’seducation.
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IftheNLSY79doesnotreportdataontheeducationofthemotherorthefather,weusethefollowingtwoimputationprocedures.
1.PartnerImputation.Ifoneparent’seducationismissing,weusetheotherparent’s.
2.MeanImputation.Ifbothparent’seducationaremissing,weusethemeaneducationofparents,differentiatingbyrace(Black,Hispanic,White)andgender.
AsshowninAppendixTables,theresultsarerobusttoexcludingtheseimputedmeasures.
Thefollowingtablesdetaileachimputationprocedure(oneobservationperindividual)forthe10,719individualsinourbasesample(seenextpage).
MotherEducationSource Freq. % Cum. NLSY79rawdata 10,093 94.16 94.16Imputedusingfather’seducation 294 2.74 96.90Imputedusinggroup’smean 332 3.10 100.00
FatherEducationSource Freq. % Cum. NLSY79rawdata 9,263 86.42 86.42Imputedusingfather’seducation 1,124 10.49 10.49Imputedusinggroup’smean 332 3.10 3.10
I.E.NLSY79:FamilyIncomein1979
ForFamilyIncomein1979,weusethenon-zerovaluesofthevariableR0217900,whichistruncatedat$75,000in2010-yearprices.Weusetheearliestnon-missingvaluein1979-1981.In81%ofthecases,thisis1979.In13%,itis1980;andin3.3%,itis1981.
Thus,ofthe132,681person-yearobservationsinTableI,8,676,wehavenon-missingdataforFamilyIncomein1979for97.3%ofthoseobservations
Fortheremaining2.7%(3,598person-yearobservations),weimputefamilyincomebyusingthemeanvalueoffamilyincomebyrace(Black,Hispanic,White).
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I.F.DataProcessingNLSY79:SampleSelectionCriteria
ThetableonthenextpagedetailshowwearriveatthenumberofobservationsineachtableusingNLSY79data.
DataProcessingNLSY79
Variable/SelectionCriteria Year-Person Individuals Dropped
Initialnumberofobservations 317,150 12,686 0Interviewed 243,641 12,686 73,509Agebetween25to55 166,250 12,264 77,391SalariedorSelf-Employed 143,583 11,780 22,667AFQT 137,272 11,133 6,311RotterScore 136,037 11,020 1,235RosenbergScore 132,681 10,719 3,356SchoolYears 132,681 10,719 0
NumberofObservations 132,681 10,719 184,469
TablesandFigures
TablesIandII:Demographics,LaborMarketOutcomesandHomeEnvironment
NumberofObservations 132,681 10,719 184,469
TableIII:SwitchingBetweenUnincorporatedandIncorporatedSelf-Employment
TableIand 132,681 10,719 184,469Self-employed,firstyearinspell 4,118 2,799 128,563Atmostoneswitchwithinself-employmentspell 4,083 2,786 35NumberofObservations 4,083 2,786 0
TableIV:JobTaskRequirementsbyEmploymentType
TableIand 132,681 10,719 184,469Excludingmissingoccupation 131,949 10,674 732NumberofObservationsPanelB.1 131,949 10,674 Lastjobassalariedworker 120,156 10,218 12,5251NumberofObservationsPanelB.2 120,156 10,218
TableVII:SelectionintoEmploymentTypesonCognitive,NoncognitiveandFamilyTraitsTableIand 132,681 10,719 IllicitIndex 125,166 10,055 7,515NumberofObservations 125,166 10,055
1ThisdropisrelativetotheobservationsinTableI.
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TableVIII:DifferencesinJobTaskRequirementsofBusinessesbyIndividualTraitsTableVIIand 125,166 10,055
Whites 69,503 5,981 55,663Males 35,012 2,964 34,491Salariedtwoyearsago 29,754 2,818 5,258Validindustrycodesinyeart 29,412 2,817 342NumberofObservations 29,412 2,817
TablesIX,X,XIandFiguresIandII:Earnings,LevelsandFirstDifferencesTableVIIand 125,166 10,055
Whites 69,503 5,981 55,663Males 35,012 2,964 34,491HourlyEarnings 32,768 2,924 2,244Full-Time;Full-Year 23,657 2,595 9,111NumberofObservations 23,657 2,595 -Firstdifferencesregressions 17,479 2,227 6,178
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II:CPS
II.A.Variables
Earnings: AnnualHoursWorked NumberofhoursworkedduringthepastcalendaryearFull-time,Full-Year Iftherespondent(1)works50ormoreweeksperyearand(2)works
2000ormorehoursperyear,and(3)works40ormorehoursperweek,thenFull-time,Full-yearissetequaltoone,otherwiseitissetequaltozero.
Earnings Wagesplusincomefrombusiness.DeflatedbytheCPIcorrespondingtowhenthoseearningswererealized.Earningsarein2010prices.
Demographics: Age TheageoftherespondentCollegeGraduate(ormore) Graduatedfromcollegeorobtainedanadvanceddegree.Educationalattainment(sixcategories)
Thesixeducationalattainmentcategoriesare:(i)completedlessthan9thgrade,(ii)completedbetween9thand11thgrade,(iii)graduatedfromhighschool,(iv)hadsomecollegeeducation,(v)graduatedfromcollege,and(vi)obtainedanadvanceddegree.
Female Equalsoneiftherespondentreportsbeingfemaleandzerootherwise.Potentialexperience Equalstheageoftherespondentminustheyearsofschoolingminus
seven,or,ifthiscomputationislessthanzero,thenpotentialexperiencesetequaltozero.
White Equalsoneiftherespondentreportsbeingwhiteandzerootherwise.Yearofbirth Thecalendaryearinwhichtherespondentwasborn.YearsofSchooling Totalyearsofeducationalattainment. Employmenttype Salaried TheCPSclassifiesallworkersineachyearaseithersalariedorself-
employed.Salariedequalsoneiftherespondentissalariedandzerootherwise.
Self-employed TheCPSclassifiesallworkersineachyearaseithersalariedorself-employed.Self-employedequalsoneiftherespondentissalariedandzerootherwise.
IncorporatedSelf-employed TheCPSclassifiesallworkersineachyearaseithersalariedorself-employed,andamongtheself-employed,indicateswhetherindividualsareincorporatedorunincorporated.Specifically,individualsareaskedabouttheiremploymentclassfortheirmainjob:“Wereyouemployedbyagovernment,byaprivatecompany,anonprofitorganization,orwereyouself-employed(orworkinginafamilybusiness)?”Thoserespondingthattheyareself-employedarefurtherasked,“Isthisbusinessincorporated?”Incorporatedself-employedequalsoneifthepersonanswersyes,andzerootherwise.
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UnincorporatedSelf-employed TheCPSclassifiesallworkersineachyearaseithersalariedorself-employed,andamongtheself-employed,indicateswhetherindividualsareincorporatedorunincorporated.Specifically,individualsareaskedabouttheiremploymentclassfortheirmainjob:“Wereyouemployedbyagovernment,byaprivatecompany,anonprofitorganization,orwereyouself-employed(orworkinginafamilybusiness)?”Thoserespondingthattheyareself-employedarefurtherasked,“Isthisbusinessincorporated?”Unincorporatedself-employedequalsoneifthepersonanswersnotothisquestionandyestobeingself-employed,andzerootherwise.
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II.B.DataProcessingCPS:SampleSelectionCriteria
ThetableonthenextpagedetailshowwearriveatthenumberofobservationsineachtableusingNLSY79datainthepaper.
DataProcessingCPS,1996-2013
Variable/SelectionCriteria Year-Person Individuals2 Dropped
Initialnumberofobservations 3,384,125 -- 0AdultCivilians 2,551,860 -- 832,265Households 2,551,836 -- 24Withpositivesampleweight 2,550,441 -- 1,395
Agebetween25to55 1,500,103 -- 1,050,338Gender,race,education 1,500,103 -- 0Potentialexperience0-50 1,500,103 -- 0Validindustrycode 1,257,925 -- 242,178Validoccupationcode(<997) 1,257,925 -- 0SchoolYears 1,257,925 -- 0
Excluding: -FarmersandFarmLaborers 1,240,776 -- 17,149-Agriculture 1,226,658 -- 14,118
Salariedorself-employed 1,225,886 -- 772
NumberofObservations 1,225,886 893,780 2,126,200
2ThenumberofindividualsisthebaseforourCPSpaneldataanalyses.
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TablesSelectionCriteria Year-Person Individuals Dropped
TableI:DemographicsandLaborMarketOutcomesbyEmploymentType
NumberofObservations 1,225,886 893,780 2,126,200
TableIV:JobTaskRequirementsbyEmploymentType
TableI 1,225,886 893,780 NumberofObservationspanelA.1 1,225,886 893,780 Panel 513,701 257,017 712,185Salariedworkerlastyear 230,330 230,330 283,371NumberofObservationspanelA.2 230,330 230,330
TableV:SelectionintoUnincorporatedandIncorporatedSelf-EmploymentTableIVpanelA.2 230,330 230,330 NumberofObservations 230,330 230,330
TableVI:TopandBottomIndustriesbyNonroutineJobTaskRequirementsTableI 1,225,886 893,780
NumberofObservations 1,225,886 893,780
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II.C.MatchedSample
Weconstructatwo-yearmatchedpanel.TheCPSinterviewsahouseholdforfourconsecutivemonths.Thenextyear,theCPSreturnstothesamelocation.Inmostcases,thesecondinterviewinvolvesthesamehouseholdasthefirstinterview.
WefollowtheguidelinesinMadrianandLefren(2000)formatchingCPShouseholdsacrosstime.Thisinvolvescheckingtheage,race,gender,education,etc.ofthoseinterviewedanddroppingindividuals(forthematchedpanelsample)wherethesedonotmatchacrosstheCPSinterviews.
Wedonotfinddifferentialselectionintothematched-CPSsampleonceweconditionondemographics(andFTFYwhenconductingtheearningsanalyses),asshowninthetablebelow.
Morespecifically,selectionintothepanelsub-sampleisnotrandom.Whitesandindividualswithlargerearningsaremorelikelytobeobservedtwoconsecutiveyearsthanothers.Theincorporatedandunincorporatedself-employedaremorelikelytobeselectedintothetwo-yearpanel(5.85%and1.7%)thanothers.Yet,conditionalonstandarddemographics,suchasgender,race,educationandpotentialexperiencethesedifferencesdisappear.
Asimple(non-parametric)waytoobservethatdifferentialselectionisnotaproblemwhenusingthematched-CPSsampleistocomparethecross-sectionCPSsamplewiththeMatched-CPSsamplebydemographicgroups.Whenwerestrictthesampletowhites,wefindmuchsmallergapsinkeymeasuresbetweentheMatched-CPSsampleandthecross-sectionsample.Forinstance,thegapinyearsofschoolingcompleted,annualhoursworked,andtheDOTmeasuresarenegligible.ThegapinannualearningsbetweentheMatched-CPSsampleandthecross-sectionsampledropsbyhalfto4%.Furthermore,whenrestrictingthesampletoFTFYwhitemen,thegapinearningsdropsto1%.ThedifferentialselectiononearningsintotheCPS-Matchedsampledropsfromapproximately7%(moreforsalariedthanincorporatedandunincorporatedself-employed)toapproximately2%.
Foracomparisonoftheearningswhenusingthefullandmatchedsamples,seeAppendixTableIXB:CPS:EarningsFull&MatchedSamples,whichshowsthattheresultsareverysimilar.
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DifferencesbetweentheCross-SectionCPSandtheMatched-PanelCPS
DifferencesinAbsoluteTerms(All-Matched)
Differencesin%(All-Matched)/AllSample: All Whites White
MalesWhiteMalesFTFY
WhiteMalesFTFY2K
All Whites White
MalesWhiteMalesFTFY
WhiteMalesFTFY2K
PanelA:AllTypesofWorkersObservations 712185 439193 224825 183224 177032
58.1% 52.2% 51.8% 50.3% 50.3%
Age -1.4 -1.2 -1.1 -1.0 -1.0
-3.5% -2.9% -2.7% -2.4% -2.4%White -0.10 0.00 0.00 0.00 0.00
-14.4% 0.0% 0.0% 0.0% 0.0%
Female 0.00 0.00 0.00 0.00 0.00
-0.1% 0.5% Yearsofschooling -0.2 -0.1 0.0 0.0 0.0
-1.6% -0.4% -0.3% -0.2% -0.2%
Meanearnings -3853 -2217 -2222 -867 -821
-8.1% -4.3% -3.5% -1.2% -1.2%Medianearnings -3930 -2225 -2010 -1158 -1171
-10.9% -5.6% -4.1% -2.2% -2.2%
Annualworkedhours -61 -49 -35 3 3
-3.0% -2.4% -1.6% 0.1% 0.1%Full-TimeFull-Year -0.03 -0.03 -0.03 0.00 0.00
-5.0% -4.4% -3.4% -0.1% 0.0%
NonroutineAnalytical -0.16 -0.06 -0.05 -0.03 -0.03
-4.0% -1.5% -1.2% -0.6% -0.6%NonroutineDCP -0.23 -0.10 -0.09 -0.05 -0.05
-7.8% -3.1% -2.7% -1.5% -1.4%
NonroutineManual 0.04 0.01 0.01 0.01 0.01
3.6% 1.5% 1.0% 0.7% 0.7%
PanelB:SalariedObservations 647422 392704 196143 160633 155473
58.4% 52.3% 52.1% 50.5% 50.5%
Age -1.4 -1.2 -1.2 -0.6 -0.7
-3.6% -3.1% -2.9% -1.4% -1.6%White -0.10 0.00 0.00 0.00 0.00
-14.9% 0.0% 0.0% 0.0% 0.0%
Female 0.00 0.00 0.00 0.00 0.00
-0.6% 0.2% Yearsofschooling -0.2 -0.1 0.0 0.0 -0.1
-1.7% -0.4% -0.3% -0.3% -0.4%
Meanearnings -3802 -2236 -2321 126 -124
-8.2% -4.4% -3.8% 0.2% -0.2%
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Medianearnings -3770 -2067 -2187 0 -405
-10.4% -5.2% -4.5% 0.0% -0.8%Annualworkedhours -59 -48 -35 -1 -4
-3.0% -2.4% -1.6% 0.0% -0.2%
Full-TimeFull-Year -0.04 -0.03 -0.03 0.00 0.00
-5.1% -4.5% -3.6% 0.0% 0.0%NonroutineAnalytical -0.16 -0.06 -0.05 -0.02 -0.01
-4.0% -1.5% -1.2% -0.5% -0.3%
NonroutineDCP -0.23 -0.10 -0.09 -0.02 0.05
-8.0% -3.2% -2.8% -0.6% 1.3%NonroutineManual 0.04 0.01 0.01 0.02 0.01
3.6% 1.5% 0.8% 1.5% 0.5%
PanelC:Self-EmployedObservations 64763 46489 28682 22591 21559
55.2% 50.8% 49.8% 49.0% 49.0%
Age -0.9 -0.7 -0.6 -0.6 -0.6
-2.0% -1.6% -1.4% -1.3% -1.3%White -0.08 0.00 0.00 0.00 0.00
-10.2% 0.0% 0.0% 0.0% 0.0%
Female 0.01 0.01 0.00 0.00 0.00
3.2% 3.1% Yearsofschooling -0.2 -0.1 -0.1 0.0 0.0
-1.4% -0.4% -0.4% -0.3% -0.3%
Meanearnings -3553 -1735 -978 126 150
-6.1% -2.8% -1.3% 0.1% 0.2%Medianearnings -2749 -1627 -1239 0 -821
-8.0% -4.5% -2.6% 0.0% -1.5%
Annualworkedhours -64 -51 -31 -1 -1
-3.1% -2.4% -1.3% 0.0% 0.0%Full-TimeFull-Year -0.03 -0.02 -0.02 0.00 0.00
-4.3% -3.6% -2.0% 0.0% 0.0%
NonroutineAnalytical -0.13 -0.06 -0.04 -0.02 -0.02
-3.1% -1.3% -0.8% -0.4% -0.4%NonroutineDCP -0.17 -0.08 -0.06 -0.02 -0.02
-4.5% -2.1% -1.3% -0.5% -0.4%
NonroutineManual 0.03 0.01 0.02 0.02 0.02
3.5% 1.4% 1.9% 1.7% 1.7%
PanelD:Self-EmployedUnincorporatedObservations 42785 29506 16440 11804 11101
56.7% 51.7% 50.3% 49.3% 49.4%
Age -1.0 -0.8 -0.7 -0.7 -0.7
-2.4% -1.9% -1.7% -1.6% -1.5%White -0.09 0.00 0.00 0.00 0.00
-12.2% 0.0% 0.0% 0.0% 0.0%
Female 0.01 0.01 0.00 0.00 0.00
2.2% 3.0% Yearsofschooling -0.2 -0.1 -0.1 -0.1 -0.1
-1.8% -0.6% -0.6% -0.4% -0.4%
Meanearnings -3150 -1905 -1375 -210 -124
-7.7% -4.4% -2.5% -0.3% -0.2%Medianearnings -2415 -1632 -1026 -102 -405
-9.8% -6.3% -3.0% -0.3% -1.0%
Annualworkedhours -66 -57 -38 -2 -4
-3.4% -3.0% -1.8% -0.1% -0.2%Full-TimeFull-Year -0.03 -0.02 -0.02 0.00 0.00
-4.4% -4.0% -2.2% 0.3% 0.0%
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NonroutineAnalytical -0.14 -0.07 -0.04 -0.02 -0.01
-3.7% -1.7% -1.0% -0.5% -0.3%NonroutineDCP -0.13 -0.05 -0.02 0.04 0.05
-4.1% -1.6% -0.5% 1.1% 1.3%
NonroutineManual 0.03 0.01 0.02 0.01 0.01
2.7% 0.6% 1.2% 0.6% 0.5%
PanelE:Self-EmployedIncorporatedObservations 21978 16983 12242 10787 10458
52.6% 49.4% 49.1% 48.6% 48.6%
Age -0.6 -0.5 -0.4 -0.4 -0.4
-1.4% -1.1% -1.0% -1.0% -1.0%White -0.06 0.00 0.00 0.00 0.00
-6.7% 0.0% 0.0% 0.0% 0.0%
Female 0.01 0.01 0.00 0.00 0.00
3.1% 2.1% Yearsofschooling -0.1 0.0 0.0 0.0 0.0
-0.4% -0.1% -0.1% -0.1% -0.1%
Meanearnings -1394 -147 467 963 1003
-1.6% -0.2% 0.4% 0.9% 0.9%Medianearnings -1390 -609 -592 -310 -728
-2.5% -1.1% -0.9% -0.4% -1.0%
Annualworkedhours -37 -30 -15 2 3
-1.6% -1.3% -0.6% 0.1% 0.1%Full-TimeFull-Year -0.02 -0.02 -0.01 0.00 0.00
-2.4% -2.3% -1.4% -0.2% 0.0%
NonroutineAnalytical -0.05 -0.02 -0.01 -0.01 -0.01
-1.1% -0.4% -0.2% -0.2% -0.2%NonroutineDCP -0.13 -0.09 -0.08 -0.07 -0.06
-2.5% -1.7% -1.4% -1.2% -1.2%
NonroutineManual 0.03 0.02 0.02 0.03 0.03
3.3% 2.1% 2.4% 3.0% 2.9%
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III:JobTaskRequirements
III.A.Basics
TheDOTwasfirstconstructedin1939tohelpemploymentofficesmatchjobseekerswithjobopenings.Itprovidesinformationontheskillsdemandedofover12,000occupations.TheDOTwasupdatedin1949,1964,1977,and1991,andreplacedbytheO*NETin1998.
Giventhetimingofourstudy,weusethe1991DOT,andconfirmtheresultswiththe1977DOT.
TheDOTaggregatesinformationintofiveskillcategories.Weusetheseaggregatedjobtaskrequirementsofindividualoccupations.TolinktheDOTmeasurestotheCPSandNLSY79data,wefollowAutor,Levy,andMurnane(2003)andusethecodesprovidedonDavidAutor’swebsite. (Reference: Autor,DavidH.,FrankLevy,andRichardJ.Murnane.2003.“Theskillcontentofrecenttechnologicalchange:Anempiricalinvestigation.”QuarterlyJournalofEconomics118(4):1279-1333.)WethenusetheunifiedIPUMSoccupationcodestohaveconsistentcodingofoccupationsofindividualsovertime.ThisgivesDOTmeasuresforeachperson-year.
III.B.Industry
Tocalculatethejobtaskrequirementsbyindustry,weusetheweightedaveragejobtaskrequirementsofworkersintheindustry.Weweightbythenumberofhoursworked(dividedby2000)ofeachworker.
III.C.Variables
NonroutineAnalytical Thedegreetowhichthetaskdemandsanalyticalflexibility,creativity,reasoning,andgeneralizedproblem-solving.
NonroutineDirection,Control,Planning
Thedegreetowhichthetaskdemandscomplexinterpersonalcommunicationssuchaspersuading,selling,andmanagingothers.
NonroutineManual Thedegreetowhichthetaskdemandseye,hand,andfootcoordination.RoutineAnalytical Thedegreetowhichthetaskrequiresthepreciseattainmentofset
standards,RoutineManual Thedegreetowhichthetaskrequiresrepetitivemanualtasks
