Religion Nurtures Some Forms of Prosocial Behavior , Education Does Not

1. ReligionNurturesSomeForms of Prosocial Behavior, Education Does Not René Bekkers Center for Philanthropic Studies VU University Amsterdam 11th ISTR Conference, July 24, 2014

2. Thanks • To the McArthur Foundation for funding the MIDUS data collection. • Colleagues who gave feedback: Dorret Boomsma, Dinand Webbink, Sara Konrath, Paul van Lange, DaniëllePosthuma. • To be submitted as a chapter for a CESifo volume published at MIT Press. 11th ISTR Conference, Münster

3. 11th ISTR Conference, Münster

4. Three questions • How alike are twins in the United States with respect to prosocial behavior? • Are differences among twins in giving and volunteering related to differences in education and religion? • If so, what explains these relationships? 11th ISTR Conference, Münster

5. Number of publicationsper yearaboutphilanthropybyacademic discipline (1899-2009; Bekkers & Dursun, 2013) 11th ISTR Conference, Münster

6. 11th ISTR Conference, Münster

7. 11th ISTR Conference, Münster

8. Ubiquitouscorrelates of philanthropy • Religion: • Affiliation (yes>no) • Denomination (Protestant>Catholic) • Participation (churchattendance) • Education: • Level achieved The variancebetweenfields of study is small 11th ISTR Conference, Münster

9. Where do the correlationsoriginate? The more general research questions: • Why are religion and educationcorrelatedwith prosocial behavior? • To whatextent are these relationships the result of environmentalinfluences? • Are these relationshipscausal? 11th ISTR Conference, Münster

10. Three ‘theories’ onphilanthropy Philanthropy variesbetweensocialgroups • because the resources of groupmembersvary; • because the socialvalues of groupsvary; • becausemembers of different groups have different self-identities. 11th ISTR Conference, Münster

11. The ideal experiment wouldrandomizeeducation VWO = highersecondaryeducation (≤ gymnasium) VMBO = lowervocationaleducation 11th ISTR Conference, Münster

12. Monozygotictwins 11th ISTR Conference, Münster

13. The uniqueenvironmentalinfluence of education Note that shared environmental influences are also excluded by design in this analysis 11th ISTR Conference, Münster

14. Whatbehavioralgeneticists do: the ACE model 11th ISTR Conference, Münster

15. ACE mediatedeffects model Koenig et al., 2007; n= 165 MZ and 100 DZ twin pairs 11th ISTR Conference, Münster

16. Biometric model fitting • Fit statistics of variousbiometric models are compared to identify the best-fitting model. • Models dependonassumptionssuch as the Equal Environments Assumption. • The EEA is oftendisputedtheoretically. • Empirical tests show it is oftenviolated. • The resulting bias, however, seems to be minor (seeFelson, Soc.Sc.Res., 2014). 11th ISTR Conference, Münster

17. Whatmoleculargeneticists do • Genome Wide Association Studies (GWAS): identify ‘candidategenes’ thatcouldexplainvariance in someoutcomevariable. • Typically, individualgeneslike OXTR and DRD4 explaintinyfractions of variance (<1%). • Typically, all single nucleotidepolymorphisms (SNPs) combinedexplainlessvariance (16% of education) than the is estimated in biometric models (35%) - missing heritabilityproblem. 11th ISTR Conference, Münster

18. Where is the socialscience? • In the varianceexplainedby shared and uniqueenvironmental factors. • Let usrule out geneticeffectsbylooking at monozygotictwinsonly. • Thischoicealsoavoidsproblemswith the EEA. • Notethat MZ twinsalso share 100% of shared environmentaleffects. 11th ISTR Conference, Münster

19. The problem • “…families whoseunobservablecharacteristicscausethem to have a high likelihood of volunteering are also more likely to educatetheirchildren, so the relationshipbetweenschooling and volunteering is just a correlationcausedbyanexcludedcommoncause.” (Gibson, 2001: 229) 11th ISTR Conference, Münster

20. This is notmyidea • In 2001, New Zealand economist John Gibson published a studyof volunteeringamong 85 identicaltwinpairs. • Thougheducation in the pooled sample is associatedwith more volunteering, pairwisecomparisonsreveal the opposite. • The twinwith more years of educationwas found to volunteerfewerhours. 11th ISTR Conference, Münster

21. The implication • Geneticeffectscause a positiveassociationbetweeneducation and volunteering. • Unique environmentaleffects of education on volunteering are negative in this sample. • Oneinterpretation of the negative effect is thatit is the result of the opportunitycost of volunteering, potentiallyamplifiedby a decisionmakingprocesswithin the household. 11th ISTR Conference, Münster

22. Relatedliterature • The twin fixed effects model has been used in economics to estimate the influence of schooling on income since the 1970s (Behrman & Taubman, 1976; Ashenfelter & Kreuger, 1994; Ashenfelter & Rouse, 1998; Isacsson, 1999; Miller, Mulvey & Martin, 1995; Bonjour et al., 2003). 11th ISTR Conference, Münster

23. Environment mediation model Notethatthis is a unique environment mediation model 11th ISTR Conference, Münster

24. The MIDUS data • Two wave longitudinal panel surveyonMidlife in the United States (1995 and 2005) sponsoredby the McArthur Foundation. • The RDD sample selection procedure includedtwinscreeningquestions. • Only English-speaking respondents aged 25-74 living in the US who were physically and mentally able to complete the interview were allowed to participate. 11th ISTR Conference, Münster

25. Assessingzygosity 11th ISTR Conference, Münster

26. Are twins different at all? Yes – here’s the discordancetable: Proportions of respondentsfrom the sametwin pair notreportingexactly the same level of education and religiousaffiliation 11th ISTR Conference, Münster

27. ACE model results 11th ISTR Conference, Münster

28. The highereducatedgive more These differences are massive: amountsdonated in the top category are ninetimes the amountdonated in the lowestcategory 11th ISTR Conference, Münster

29. The highereducatedvolunteer more Again, largedifferences 11th ISTR Conference, Münster

30. Informal prosocial behaviors PerhapsAmericanswithlesseducationknow more people in need of support? 11th ISTR Conference, Münster

31. The religiousgive more Religiousgiving is included in thisfigure. Excludingdonations to religion, the differences are much smaller. 11th ISTR Conference, Münster

32. The religiousvolunteer more Thisfigureincludesvolunteering for religiousorganizations. 11th ISTR Conference, Münster

33. Informal prosocial behaviors PerhapsAmericanswhoattendchurchlessoftenknow more people in need of financialassistance and support? 11th ISTR Conference, Münster

34. Twobasicregression models • Betweeneffects model: ignores the twin pair structure, replicatesbivariate analyses. Includesgenetic + environmentaleffects. • Within MZ twinfixedeffects model: does the highereducated / more religioustwin of an MZ pair give and volunteer more than the lesseducated / religiousco-twin? Includesenvironmentaleffectsonly. 11th ISTR Conference, Münster

35. Education and giving 11th ISTR Conference, Münster

36. Twofurther models • Reducedformwithin MZ twin model: excludesreligiousdenominationdummies, retainingeducation, churchattendance and strength of religiosity. • Mediatedreducedformwithin MZ twin model: addssocialresponsibility, prosocial self-identity, householdincome, and assets. 11th ISTR Conference, Münster

37. Education and givingamongMZs 11th ISTR Conference, Münster

38. Educationestimatesontotalgiving 11th ISTR Conference, Münster

39. Education and volunteering *** *** *** p <.001 11th ISTR Conference, Münster

40. Churchattendance and giving *** *** *** *** 11th ISTR Conference, Münster

41. Churchattendance and volunteering 11th ISTR Conference, Münster

42. Strength of religiosity and giving * * *p <.05 * 11th ISTR Conference, Münster

43. Religiosity and volunteering *** *** *** *** *** ** ** ***p <.001; ** p < .01 11th ISTR Conference, Münster

44. 11th ISTR Conference, Münster

45. 11th ISTR Conference, Münster

46. Conclusions • The associationbetween the level of education and giving and volunteering is due to genetic or shared environmentaleffects. • The associationbetweenreligiosity and charitablegiving is duetouniqueenvironmentaleffects, but it is limited to churchcontributions. • Religiositynurturesvolunteering, alsobeyondreligiousorganizations. 11th ISTR Conference, Münster

47. Mediation • Educationhardlymediatesuniqueenvironmentalinfluences on giving (-0.5%) or volunteering (1.8%). • Religionmediatesuniqueenvironmentalinfluences on giving (15.6%) but not on volunteering (2.0%). • Educationeffects are partlymediated (25%) byincome and assets. • Religiosityeffects are mediatedby prosocial self-identity (55%), butnotby prosocial values. 11th ISTR Conference, Münster

48. Orvice versa • Perhapsvolunteeringnurturesreligiosity. • Or perhapsanomitted (shared?) environmental effect nurturesvolunteering and religiosity. • We cannotinfercausalityfrom the twinfixedeffects model. • But we can look at changes in religiosity and volunteeringbetween the twowaves. 11th ISTR Conference, Münster

49. …and? • Respondents who quit volunteering between the first and the second wave are less frequently attending church and report lower strength of religiosity in the second wave than in the first wave. • Respondents who started volunteering are more frequently attending church in the second wave. 11th ISTR Conference, Münster

50. The measurementerrorproblem • Coulddifferentialmeasurementerrorexplain the pattern of results? • That is unlikely. The test-retestcorrelation of education is higher (.87) thanthat of the frequency of churchattendance (.72). It is similar to strength of religiosity (.84). 11th ISTR Conference, Münster