《实验经济学》课程教学资源（参考文献）Testing for Altruism and Social Pressure in Charitable Giving

THE QUARTERLY JOURNAL OF ECONOMICS Vol.127 February 2012 Issue 1 TESTING FOR ALTRUISM AND SOCIAL PRESSURE IN CHARITABLE GIVING STEFANO DELLAVIGNA JOHN A.LIST ULRIKE MALMENDIER ne ver?We that distinguishes two types of motivation:individuals like to give,for example due to altruism or warm glow,and individuals would rather not give but dislike ue to s al pre ure. e design ado rund-r n their doorknobs.Thus the oid the fund-r that the flyer reduces the share of households opening the door by9%to25 and,if the flyer allows checking a Do Not Disturb box,reduces giving by 28% e latter de smaller 10 to-door giving.Combining data from thisd entary field exr we structurally estimate the model.The estimated social pressure cost of saying no toa solicitor is $3.80 for an in-state charity and $1.40 for an out-of-state charity Cha We thank theitor,four urabh B rgava,David C ard,Gary Lawrence Katz.Patrick Kline.Stephan Meier.Klaus Schmidt.Bruce e Shearer I Sturm and the au ces at the o Booth Sch ool of Busi- ty of UC Berk vers all of University of Rotterdam,University of Zurich,Washington University(St.Louis). rStudies),the Sa Eco ed Field Stu er,Jim Cai.Matthe for excellent researchitane Oxford Uni behalf of President The .com 2ics(2012)127.1-56.do110.1093/aie/air050 Advance Access publication on January 18.2012. 1

THE QUARTERLY JOURNAL OF ECONOMICS Vol. 127 February 2012 Issue 1 TESTING FOR ALTRUISM AND SOCIAL PRESSURE IN CHARITABLE GIVING∗ STEFANO DELLAVIGNA JOHN A. LIST ULRIKE MALMENDIER Every year, 90% of Americans give money to charities. Is such generosity necessarily welfare enhancing for the giver? We present a theoretical framework that distinguishes two types of motivation: individuals like to give, for example, due to altruism or warm glow, and individuals would rather not give but dislike sayingno, forexample, duetosocial pressure. Wedesigna door-to-doorfund-raiser in which some households are informed about the exact time of solicitation with a flyer on their doorknobs. Thus, they can seek or avoid the fund-raiser. We find that the flyer reduces the share of households opening the door by 9% to 25% and, if the flyer allows checking a Do Not Disturb box, reduces giving by 28% to 42%. The latter decrease is concentrated among donations smaller than $10. These findings suggest that social pressure is an important determinant of door￾to-door giving. Combining data from this and a complementary field experiment, we structurally estimate the model. The estimated social pressure cost of saying notoa solicitoris $3.80 foranin-statecharityand$1.40 foranout-of-statecharity. Our welfare calculations suggest that our door-to-door fund-raising campaigns on average lower the utility of the potential donors. JEL Codes: C93, D03, H41. ∗We thank the editor, four referees, Saurabh Bhargava, David Card, Gary Charness, Constanca Esteves-Sorenson, Bryan Graham, Zachary Grossman, Lawrence Katz, Patrick Kline, Stephan Meier, Klaus Schmidt, Bruce Shearer, Joel Sobel, Daniel Sturm and the audiences at the Chicago Booth School of Busi￾ness, Columbia University, Harvard University, HBS, University of Amsterdam, University of Arizona, Tucson, UC Berkeley, USC (Marshall School), UT Dallas, University of Rotterdam, University of Zurich, Washington University (St. Louis), Yale University, the NBER Summer Institute (Labor Studies), the San Francisco 2009 Applied Micro Conference, the 2009 Berkeley Conference in Behavioral Economics, the 2010 UCSB Conference on Experimental Economics, the Munich Workshop on Natural Experiments and Controlled Field Studies, and the ASSA 2009 Meetings for helpful comments. We alsothank Daniel Acland, Diane Alexan￾der, JimCai, MatthewLevy, VerateVelde, XiaoyuXia, andespeciallyGautamRao for excellent research assistance. c The Author(s) 2012. Published by Oxford University Press, on behalf of President and Fellows of Harvard College. All rights reserved. For Permissions, please email: journals. permissions@oup.com. The Quarterly Journal of Economics (2012) 127, 1–56. doi:10.1093/qje/qjr050. Advance Access publication on January 18, 2012. 1 by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

2 QUARTERLY JOURNAL OF ECONOMICS I.INTRODUCTION In the United States,approximately%findividuals donate money each year.There is at least one capital campaign to raise $25 million or more under way in virtually every major population center in North America.Smaller capital campaigns are even r-to-door dri e and mail ng in popularity.Despite the ubiquity fund-raising,we still have an imperfect understanding of the motivations for giving and the welfare implications for the giver (see,e.g.,Andreoni 2006). In this article,we consider two broad classes of motiva- tions.First.individ may enjoy For example,hey car about a specific warm glow of giving. Second,individuals may give,despite not liking to give to the charity,because the solicitor effectively placed them under social pressure to give.Such givers would rather avoid the personal interaction or.The two motivations ha are implications.The altruism(or warm glow)mode (Becker 1974;Andreoni 1989,1990)posits that giving is mostly supply-driven,and that it is utility-maximizing for the giver to give.Under this model,donations unambiguously enhance the giver's utility as well as societal welfare.The social pressure model (Ake lof and K n2000)p osits that giv ing is most demand-driven,and that giving may be utility-reducing for the giver. We test for these two types of motivations in the context of in-person,unsolicited donation requests.Building on a theoretical model w e design a field xperim ment that allows us totest whether giving is welfare enha welfare-reduci ng for the giver We complement the reduced-form experimental evidence with structural estimates of the model parameters.The structural es- timation allows us to decompose the share of giving that is due to altruism versus social pressure and to quantitatively evaluate the welfare effects r the giver.In this s way,the empiric sand theory are intertwined in a manner that is rare in this literature.To our knowledge,this article is the first in the behavioral literature to provide structural estimates of welfare implications of a field prment.Moreover,while the fund-raising set-up is sp it sho ses a genera toward be and provides etter understanding the underpinnings for giving more generally

2 QUARTERLY JOURNAL OF ECONOMICS I. INTRODUCTION IntheUnitedStates, approximately90% ofindividuals donate money each year. There is at least one capital campaign to raise $25 millionormoreunderwayinvirtuallyeverymajorpopulation center in North America. Smaller capital campaigns are even more numerous, with phoneathons, door-to-door drives, and mail solicitations increasing in popularity. Despite the ubiquity of fund-raising, we still have an imperfect understanding of the motivations for giving and the welfare implications for the giver (see, e.g., Andreoni 2006). In this article, we consider two broad classes of motiva￾tions. First, individuals may enjoy giving. For example, they care about a specific worthy cause or like the warm glow of giving. Second, individuals may give, despite not liking to give to the charity, because the solicitor effectively placed them under social pressure to give. Such givers would rather avoid the personal interaction with the solicitor. The two motivations have very different welfareimplications. Thealtruism(orwarmglow) model (Becker 1974; Andreoni 1989, 1990) posits that giving is mostly supply-driven, and that it is utility-maximizing for the giver to give. Under this model, donations unambiguously enhance the giver’s utility as well as societal welfare. The social pressure model (Akerlof and Kranton 2000) posits that giving is mostly demand-driven, and that giving may be utility-reducing for the giver. We test for these two types of motivations in the context of in-person, unsoliciteddonationrequests. Buildingona theoretical model, we design a fieldexperiment that allows us totest whether giving is welfare-enhancing or welfare-reducing for the giver. We complement the reduced-form experimental evidence with structural estimates of the model parameters. The structural es￾timation allows us to decompose the share of giving that is due to altruism versus social pressure andtoquantitatively evaluate the welfare effects for the giver. In this way, the empirics and theory are intertwined in a manner that is rare in this literature. To our knowledge, this article is the first in the behavioral literature to provide structural estimates of welfare implications of a field experiment. Moreover, while the fund-raising set-up is specific, it showcases a general methodology and provides a first step toward better understanding the underpinnings for giving more generally. by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

TESTING FOR ALTRUISM AND SOCIAL PRESSURE Our field experiment revolves around a door-to-door fund raising drive for two charities,a local children's hospital,which has a reputation as a premier hospital for children,and an out- of-state charity,unfamiliar to most solicitees.Between April and October 2008 proached 7,668 households in the to e crucial spect of the experin ental desic toallow individuals to sort,that is,to either seek orav solicitor.In our first treatment,a flyer on the doorknob notifies households one day in advance about the one-hour time interval in which a solicitor will arrive at their homes the next day.In the se cond treatment,opt- also includes a bo to be checked if the househ es not w t to o be disturbe compare these two conditi to a b aseline treatment,whereir solicitors approach households in the usual manner without a flyer.We estimate the treatment effects on both the share of households that open the door and the share that give. This design allows for a simple test of(pure or impure)altru- ism versus so press e in doo or giving.Ifalt ruism is th main driver of giving,the flyer sh ould increa ase both the presence at home and giving.Because giving is utility-enhancing,givers should sort into staying at home,provided that alternative ways of donating to these charities require more effort.In addition. givers who would like to give in response to the flyer but who find it too costly to be at ho should give to the ch means,such as mailing a eck.Co nv rsely,if so I pressure is the main driver of giving,the flyer should lower both the frequency of opening the door and the frequency of giving.Since being asked to give is welfare-diminishing,potential givers should sort out of the door and should not give via Internet or check ese forms of donatio are I su t to sc pressure We report four main n result which are sim ar acros two charities.First,the flyer lowers the frequency ofopening the door. Relative to a baseline rate of 41 percentage points,the share of households opening the door is 9%lower after receiving the Aver and 23%lo ng the flyer with an opt-out o (includi ng the h seholds that check th e opt-out box nd,the simple flyer s not reduce giving.However the flyer with an opt-out checkbox decreases giving significantly,by 28%relative to a baseline of 7%for the local charity and 40%relative to a 5% baseline giving for the out-of-state charity.Third,the decrease in giving in the opt-out treatment is driven by small donations up to $10: above $10, instead incre ease slightly (not

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 3 Our field experiment revolves around a door-to-door fund￾raising drive for two charities, a local children’s hospital, which has a reputation as a premier hospital for children, and an out￾of-state charity, unfamiliar to most solicitees. Between April and October 2008, we approached 7,668 households in the towns sur￾rounding Chicago. The crucial aspect of the experimental design is to allow individuals to sort, that is, to either seek or avoid the solicitor. In our first treatment, a flyer on the doorknob notifies households one day in advance about the one-hour time interval in which a solicitor will arrive at their homes the next day. In the second treatment, opt-out, the flyer also includes a box to be checked if the household does not want to be disturbed. We compare these two conditions to a baseline treatment, wherein solicitors approach households in the usual manner without a flyer. We estimate the treatment effects on both the share of households that open the door and the share that give. This design allows for a simple test of (pure or impure) altru￾ismversus social pressureindoor-to-doorgiving. If altruismis the main driver of giving, the flyer should increase both the presence at home and giving. Because giving is utility-enhancing, givers should sort into staying at home, provided that alternative ways of donating to these charities require more effort. In addition, givers who would like to give in response to the flyer but who find it too costly to be at home should give to the charity via other means, such as mailing a check. Conversely, if social pressure is themaindriverofgiving, theflyershouldlowerboththefrequency of opening the door andthe frequency of giving. Since being asked to give is welfare-diminishing, potential givers should sort out of openingthedoorandshouldnot givevia Internet orcheckbecause these forms of donation are not subject to social pressure. We report four main results, which are similar across the two charities. First, the flyer lowers the frequency of opening the door. Relative to a baseline rate of 41 percentage points, the share of households opening the door is 9% lower after receiving the flyer and 23% lower after receiving the flyer with an opt-out box (including the households that check the opt-out box). Second, the simple flyer does not reduce giving. However, the flyer with an opt-out checkbox decreases giving significantly, by 28% relative to a baseline of 7% for the local charity and 40% relative to a 5% baseline giving for the out-of-state charity. Third, the decrease in giving in the opt-out treatment is driven by small donations up to $10; donations above $10, instead, increase slightly (not by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

4 QUARTERLY JOURNAL OF ECONOMICS significantly).Fourth,there is no effect on donations via mail or ternet In contrast to the substantial don ation rate in person. only one household out of 7,668 gave through these other means Overall.the reduced-form estimates indicate that both altru- ism and social pressure are important determinants of giving in this setting,with stronger evidence for the role of social pressure. The lov of households opening the door afte receiv ing a flyer indicates that hou seholds sare,on average,trying to avoid solicitors,consistent with social pressure.The lack of an effect of the baseline flyer on giving is consistent with opposing effects of altruism and social pressure approximately canceling each other out.The decrease in giving after a flyer with opt out box s role of social Whe the islowered ck on a box su giving due to social pressure decreases. This interpretation is consistent with the reduction occurring almost exclusively among small donations,which are more likely due to social pressure than large donations.The social pre consistent with the lack of donatic ide er several alt native interpreta st,flyer could be taken as a signal of lower quality of the charity.This interpretation can explain the reduction in answering the door and in giving with a flyer,but does not immediately explain why only small donations decrease,not large donations.Second, individuals might donate to send(costly)sig nals to themselves or to others that they are generous(Bod nd Prelec 2003;Ber abou and Tirole 2006;Grossman 2010).This interpretation can explain our findings to the extent that avoiding a solicitor does not send the same negative signal as saying no to the solicitor.This explanation.however.is less consistent with the fact that 12%of households in the opt-out treatment check the opt-out box,which signal to the f,as w ell as possibly the ighb Third,people may dislike spending time with the solicitor,for example,because of the time involved,despite wanting to donate in principle.These potential donors,however,when alerted of a campaign by a dver.should seek alternative ways to give that do not involve e per onal interaction instead we obse no such tution To assess the welfare effects of giving,we structurally es timate the model parameters.We combine data from the treat. ments with complementary field experiments on the value oftime, run in the same geographical areas in 2008 and 2009.These

4 QUARTERLY JOURNAL OF ECONOMICS significantly). Fourth, there is no effect on donations via mail or Internet. In contrast to the substantial donation rates in person, only one household out of 7,668 gave through these other means. Overall, the reduced-form estimates indicate that both altru￾ism and social pressure are important determinants of giving in this setting, with stronger evidence for the role of social pressure. The lower frequency of households opening the door after receiv￾ing a flyer indicates that households are, on average, trying to avoid solicitors, consistent with social pressure. The lack of an effect of the baseline flyer on giving is consistent with opposing effects of altruism and social pressure approximately canceling each other out. The decrease in giving after a flyer with opt￾out box supports the role of social pressure. When the cost of avoiding the solicitor is lowered (a simple check on a box suffices), giving due to social pressure decreases. This interpretation is consistent with the reduction occurring almost exclusively among small donations, which are more likely due to social pressure than large donations. The social pressure interpretation is also consistent with the lack of donations via mail or Internet. We consider several alternative interpretations. First, flyers could be taken as a signal of lower quality of the charity. This interpretation can explain the reduction in answering the door and in giving with a flyer, but does not immediately explain why only small donations decrease, not large donations. Second, individuals might donate to send (costly) signals to themselves or to others that they are generous (Bodner and Prelec 2003; Ben￾abou and Tirole 2006; Grossman 2010). This interpretation can explainourfindings totheextent that avoidinga solicitordoes not send the same negative signal as saying no to the solicitor. This explanation, however, is less consistent with the fact that 12% of households in the opt-out treatment check the opt-out box, which is a signal to the solicitor, as well as possibly to the neighbors. Third, people may dislike spending time with the solicitor, for example, because of the time involved, despite wanting to donate in principle. These potential donors, however, when alerted of a campaign by a flyer, should seek alternative ways to give that do not involve personal interaction; instead, we observe no such substitution. To assess the welfare effects of giving, we structurally es￾timate the model parameters. We combine data from the treat￾ments withcomplementaryfieldexperiments onthevalueof time, run in the same geographical areas in 2008 and 2009. These by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

TESTING FOR ALTRUISM AND SOCIAL PRESSURE experiments are designed to estimate a key parameter in the fund raising treatments,the sensitivity of home presence to incentives, which is otherwise identified only parametrically.We ask 11,900 households to complete a survey and vary the payment($0,$5,or $10).the duration (5 or 10 minutes).and whether the su announced a flyer, optout option).Higher payments and shorter duration increase the presence at home up to 16%and increase survey completion by 17-82%. we use a minimum-distance estimator on the combined data from the charity and the survey experiments.The estimator minimizes the distance betwe on the model and the moments predicted by obs ed moment he moments are the pre abil- ities of opening the door,giving different amounts,completing a survey,and opting out.Key parameters are the share of altruists, the curvature of the altruism function,and the social pressure cost of saying no in person to a solicitor.We estimate that 75% of solicitees have no altruism toward the charities,but there is tial h eroge Among the altr uists,the utility fro giving due to altruism is steeply concave in the amount given,with almost no predicted donation above $50,consistent with warm- glow rather than pure altruism.The estimated social pressure cost of giving zero is $3.75(and significantly different from $0)for the in-state charity and $1.44(marginally significant)for the out- of-state cha ity.As a result of s rity of do nors give more th an they would】 have f donors erive negative utility from the fund-raising interaction and would have preferred to sort out. Given the large social pressure costs.our door-to-door cam- paigns lower the utility of the solicited households on average n 6ys1.10 avisit is elfar per househe con od fo the in-state charity S044 for the out-of-state charity.The morev impact for the in-state charity is counterintuitive because more people are willing to donate to this better-liked charity.At the same time,however,the social pressure cost of saying no is also significantly higher for the loca al charity,and the ond force dominates If we take our fund-raising campaigns to be representative of door-to-door solicitations,unsolicited campaigns lead to utility losses for the givers in the order of hundreds of millions of dollars. The campaigns may still increase overall welfare,though only if the charities s spend the e money very effectively;in our campaign

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 5 experiments aredesignedtoestimateakeyparameterinthefund￾raising treatments, the sensitivity of home presence toincentives, which is otherwise identified only parametrically. We ask 11, 900 households to complete a survey and vary the payment ($0, $5, or $10), the duration (5 or 10 minutes), and whether the surveys are announced (with a flyer, with or without opt-out option). Higher payments and shorter duration increase the presence at home up to 16% and increase survey completion by 17–82%. We use a minimum-distance estimator on the combined data from the charity and the survey experiments. The estimator minimizes the distance between the moments predicted by the model and the observed moments. The moments are the probabil￾ities of opening the door, giving different amounts, completing a survey, and opting out. Key parameters are the share of altruists, the curvature of the altruism function, and the social pressure cost of saying no in person to a solicitor. We estimate that 75% of solicitees have no altruism toward the charities, but there is substantial heterogeneity. Among the altruists, the utility from givingduetoaltruismis steeplyconcaveintheamount given, with almost no predicted donation above $50, consistent with warm￾glow rather than pure altruism. The estimated social pressure cost of giving zerois $3.75 (and significantly different from $0) for the in-state charity and $1.44 (marginally significant) for the out￾of-state charity. As a result of social pressure, a majority of donors give more than they would have liked to. Half of donors derive negative utility from the fund-raising interaction and would have preferred to sort out. Given the large social pressure costs, our door-to-door cam￾paigns lower the utility of the solicited households on average. In the benchmark specification, a visit is estimated to lower welfare by $1.10 per household contacted for the in-state charity and by $0.44 for the out-of-state charity. The more negative welfare impact for the in-state charity is counterintuitive because more people are willing to donate to this better-liked charity. At the same time, however, the social pressure cost of saying no is also significantly higher for the local charity, and the second force dominates. If we take our fund-raising campaigns to be representative of door-to-door solicitations, unsolicited campaigns lead to utility losses for the givers in the order of hundreds of millions of dollars. The campaigns may still increase overall welfare, though only if the charities spend the money very effectively; in our campaign, by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

6 QUARTERLY JOURNAL OF ECONOMICS we raised net donations of only $0.24 per household contacted for the in-state charity,and no net donation for the out-of-state charity. An important qualification is that our design identifies rea- sons for marginal,as opposed to infra-marginal,giving.House- holds that do not give to our fund-raiser.or give only due to social pressure,likely co ntributed to other charities.The motives for giving identified in this article may not generalize to infra marginal giving,which is more likely motivated by altruism and desire for status.By the same token,however,it would be a mistake to ignore the high-pressure giving requests studied herein,or to assume that the motives for infra-marginal giving studied in the lite ratu apply.Small ital ca like the one studied in this artic cle,are common a nd reveal a different face of the motivations for giving. Our findings can be used as an argument to introduce a do- not-solicit or do-not-call list for charities.However,they also sug- gest an alternative:providing households with the opportunity to out.Intro nits or e lin ates a together,the wel e losses fo the solic itees.Interestingly,introducing sorting can also increase charitable fund-raising,and be a win-win solution:even a limited amount of sorting in of altruistic givers,who give larger amounts, is likely to counterbalance the sorting out of givers motivated by social pressure,who give smaller amounts. A methodological utio f this article is the close tie between the behavioral model and the field experiment,allowing for structural estimation of the underlying parameters,which is surprisingly rare.Of all field experiments published in top five iournals from 1985 to 2010.only two have this feature (Card,DellaVigna,and Malmendier 2011).A small literature in structural behe estimate s beha vioral odel observation Idata,including Laibson,Repetto,and Tobacman (2007)and Conlin,O'Donoghue,and Vogelsang (2007). Our article adds to several other strands of literature.It provides field evidence about social preferences to complement the laboratory evidence(Fehr and Gachter 2000:Charr ess and Rabin 2002;ar Da nd Da 2006:L ear Malmendier,and eber forth oming).The study also relates to the empirical and theoretical literature on optimal fund-raising (e.g.,List and Lucking-Reiley 2002;Andreoni 2006;Landry et al 2006:Ariely,Bracha,and Meier 2009;Croson and Shang 2009;

6 QUARTERLY JOURNAL OF ECONOMICS we raised net donations of only $0.24 per household contacted for the in-state charity, and no net donation for the out-of-state charity. An important qualification is that our design identifies rea￾sons for marginal, as opposed to infra-marginal, giving. House￾holds that do not give to our fund-raiser, or give only due to social pressure, likely contributed to other charities. The motives for giving identified in this article may not generalize to infra￾marginal giving, which is more likely motivated by altruism and desire for status. By the same token, however, it would be a mistake to ignore the high-pressure giving requests studied herein, or to assume that the motives for infra-marginal giving studied in the literature apply. Small capital campaigns, like the onestudiedinthis article, arecommonandreveal a different facet of the motivations for giving. Our findings can be used as an argument to introduce a do￾not-solicit or do-not-call list for charities. However, they also sug￾gest an alternative: providing households with the opportunity to sort or, even better, opt out. Introducing sorting opportunities in fund-raising limits or eliminates altogether, the welfare losses for the solicitees. Interestingly, introducing sorting can also increase charitable fund-raising, and be a win-win solution: even a limited amount of sorting in of altruisticgivers, whogive larger amounts, is likely to counterbalance the sorting out of givers motivated by social pressure, who give smaller amounts. A methodological contribution of this article is the close tie between the behavioral model and the field experiment, allowing for structural estimation of the underlying parameters, which is surprisingly rare. Of all field experiments published in top five journals from 1985 to 2010, only two have this feature (Card, DellaVigna, and Malmendier 2011). A small literature in structural behavioral economics estimates behavioral models on observational data, including Laibson, Repetto, and Tobacman (2007) and Conlin, O’Donoghue, and Vogelsang (2007). Our article adds to several other strands of literature. It provides field evidence about social preferences to complement the laboratory evidence (Fehr and G¨achter 2000; Charness and Rabin 2002; and especially Dana, Cain, and Dawes 2006; Lazear, Malmendier, and Weber forthcoming). The study also relates to the empirical and theoretical literature on optimal fund-raising (e.g., List and Lucking-Reiley 2002; Andreoni 2006; Landry et al. 2006; Ariely, Bracha, and Meier 2009; Croson and Shang 2009; by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

TESTING FOR ALTRUISM AND SOCIAL PRESSURE > Fong and Luttmer 2009).Finally,it adds to the literature on social pressure (Asch 1951;Milgram 1963;Garicano,Palacios-Huerta. and Prendergast 2005;Gerber,Green,and Larimer 2008;Mas and Moretti 2009). The rest of the article proceeds as follows.In Section II with altru rre Weintroduce the experimentaldS e m discuss the reduced-form results in Section IV.In Section V,we structurally estimate the parameters.In Section VI,we discuss alternative interpretations.Section VII concludes. II.MODE We model the behavior of an individual whose home is visited by a fund-raiser.We distinguish between the standard case of an unanticipated visit and that of an anticipated visit.in the latter case,a flye r announces the visit and the individual can alter the probability of being at h e and opening th d uS: here the setting and predictions.The technical details,including Lemmas are in the Appendix,and the proofs are in the Online Appendix. IⅡ.A.Setup We consider a two-stage game betw n a potential giver and a solicitor.For convenience,we denote the potential giver,or solicitee,simply as giver.In the first stage,the giver may receive a flyer of the upcoming visit and,if so,notices the flyer with probability r (0,1].In the second stage,the solicitor visits the home.The p s the door obability h.If she did not notice yer (o rece ve on h is equal to a basel probability ho e(0,1).If she noticed the flyer,she can adjust the probability to h E[0,1]at a cost c(h),with c(ho)=0,c'(ho)=0,and c"()>0.That is,the marginal cost of small adjustments is small, but larger adjustments have an increasingly large cost.We do not metry around ho and we allow for ner solutions at If the giver is present,she donates an amount g>0.If she is absent,there is no in-person donation (g =0).The giver can donate through other channels,such as via mail or online,after learning about the charity from the solicitor or the flver.The giver has utility (1) U(g,gm)=u (W-g-gm)+av(g+0gm,G-i)-s(g)

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 7 FongandLuttmer2009). Finally, it adds totheliteratureonsocial pressure (Asch 1951; Milgram 1963; Garicano, Palacios-Huerta, andPrendergast 2005; Gerber, Green, andLarimer2008; Mas and Moretti 2009). The rest of the article proceeds as follows. In Section II we present a simple model of giving with altruism and social pressure. Weintroducetheexperimental designinSection III and discuss the reduced-form results in Section IV. In Section V, we structurally estimate the parameters. In Section VI, we discuss alternative interpretations. Section VII concludes. II. MODEL Wemodel the behavior of an individual whose home is visited by a fund-raiser. We distinguish between the standard case of an unanticipated visit and that of an anticipated visit. In the latter case, a flyer announces the visit and the individual can alter the probability of being at home and opening the door. We discuss here the setting and predictions. The technical details, including Lemmas are in the Appendix, and the proofs are in the Online Appendix. II.A. Setup We consider a two-stage game between a potential giver and a solicitor. For convenience, we denote the potential giver, or solicitee, simply as giver. In the first stage, the giver may receive a flyer of the upcoming visit and, if so, notices the flyer with probability r ∈ (0, 1]. In the second stage, the solicitor visits the home. The giver opens the door with probability h. If she did not notice the flyer (or did not receive one), h is equal to a baseline probability h0 ∈ (0, 1). If she noticed the flyer, she can adjust the probability toh ∈ [0, 1] at a cost c (h), with c(h0)= 0, c0 (h0)= 0, and c00(∙) > 0. That is, the marginal cost of small adjustments is small, but larger adjustments have an increasingly large cost. We donot require symmetry around h0 and we allow for corner solutions at h = 0 or h = 1. If the giver is present, she donates an amount g ≥ 0. If she is absent, there is no in-person donation (g = 0). The giver can donate through other channels, such as via mail or online, after learning about the charity from the solicitor or the flyer. The giver has utility (1) U (g, gm) = u (W − g − gm) + av (g + θgm, G−i) − s (g). by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

8 QUARTERLY JOURNAL OF ECONOMICS sumption,u,is derived from the pregiving wealth minus the donations given to the solicitor (g)and through other channels such as mail(gm).Giving through other channels gm involves additional costs,such as finding an envelope and stamp,equalto(1-0)gmm,with00 and u"(.)0,v(,) 0 denotes the level of altruism,3 and the overall utility from giving is av(G-i+g+0gm). In the case of impure altruism,the agent cares about the warm glow vingg.Hence,v()does no t nece sarily depend on the giving of others,G-i,and a >0 captures the intensity of the warm glow.We make the same assumptions v>0,<0, and lim 。w'(g..)=0 Finally,in the case of spite towards the charity,the agent dislikes giving to the charity The utilityis(G i+g+egm),with <0 cap the e intensity of spite.I u04 sume tha the disutility of giving increases with the donation in a convex L.The ke is more yesutsgeneraiaetoaiadoastofgiingbymalbuthealebrn 2.We allow for giving to exceed current wealth,that is,the caseg+gm W. In prac Th e,this case is u y to ma of the charity. the belief of the donor about the quality charit Under the

8 QUARTERLY JOURNAL OF ECONOMICS Theutilityofprivateconsumption, u, is derivedfromthepregiving wealth W minus the donations given to the solicitor (g) and through other channels such as mail (gm). Giving through other channels gm involves additional costs, such as finding an envelope andstamp, equal to(1−θ)gm, with0 ≤ θ 0 and u00( ∙ ) ≤ 0. Notice that the utility of private consumption can include the utility from infra-marginal giving to other charities.2 The utility of giving to the charity, v, allows for pure and impure altruism (warm glow), or prestige (Harbaugh 1998). Since the experiment is not designed to separate pure altruism, im￾pure altruism, or prestige but altruism from social pressure, we use a specification that is general enough to encompass both. We also allow for negative social preferences, or spite (Levine 1998), towards the charity. In the case of pure altruism, the agent cares about the total contributions to the charity, G−i + g + θgm, where G−i is the giving of others. In this case, we can think of v (G−i + g + θgm) as the production function of the charity, which is increasing in the donation g but has decreasing returns: v0 g(∙, ∙) > 0, v00 g,g(∙, ∙) 0, v00 g,g W. In practice, this case is unlikely to matter. 3. The parameter a can also capture the belief of the donor about the quality of the charity. 4. Under the warm-glow model, an alternative interpretation of θ is that the charity receives the full amount gm (i.e., there are no costs of giving via mail), but the impersonal mean lowers warm glow by a factor θ. by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 9 manner:v>0and >0.Here,we are abusing notation since the function v differs for a >0 (altruism)and a 0,v-to denote the function for a 0 does not depend on the social pressure cost S),while donations smaller than g*may be due to altruism m or social pressure.Giving can occur also wi th

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 9 manner: v0 g > 0 and v00 g,g > 0. Here, we are abusing notation since the function v differs for a ≥ 0 (altruism) and a aˉ), the donor gives more than gs . Any giving above gs is due to altruism (hence the threshold aˉ > 0 does not depend on the social pressure cost S), while donations smaller than gs may be due to altruism or social pressure. Giving can occur also with by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from

10 QUARTERLY JOURNAL OF ECONOMICS 现 0 a=0,h=ho FIGURE I Regions of Giving g and Probability of Home Presence h Figure indicates the different regions for giving,no giving lg=0),small giving 0g").and the different regions ility of being at home,avoiding thes icitor [h hol,and seeking pressure paran piteful agents(a u'(W)and hence a<). Giving via Mail.Conditional on not being at home,a giver who was informed about the fund-raising via a flyer decides whether to give via mail gm.Note that the only reason to give via mail is altruism.Giving via mail is increasing in altruis provided 0.For given altruisn 0 the leve giving via mail re eceived by the charity(g(a))is always smaller than the level of giving in person conditional on being at home (g(a,S)) (Lemma 1B). Presence at Home.In the first stage,the giver opens the door with robability ho if the visit is ticipa (no yer or with probability 1-r,despite a flyer). f the visit is anticipated (flyer),she optimizes h given her utility from being at home, u(W-g)+av(g,G_i)-s(g*),and her utility from not being at home,u (W-gm)+av (0gm,G_i):

10 QUARTERLY JOURNAL OF ECONOMICS FIGURE I Regions of Giving g and Probability of Home Presence h Figure indicates the different regions for giving, no giving [g = 0], small giving [0 gs], and the different regions for the probability of being at home, avoiding the solicitor [h h0]. The regions are a function of the altruism parameter a and of the social pressure parameter S. spiteful agents (a u0 (W) and hence a 0. For given altruism a, the level of giving via mail received by the charity (θg∗ m (a)) is always smaller than the level of giving in person conditional on being at home (g∗ (a, S)) (Lemma 1B). Presence at Home. In the first stage, the giver opens the door with probability h0 if the visit is unanticipated (no flyer or, with probability 1 − r, despite a flyer). If the visit is anticipated (flyer), she optimizes h given her utility from being at home, u (W − g∗) + av (g∗, G−i) − s (g∗), and her utility from not being at home, u (W − g∗ m) + av (θg∗ m, G−i): by guest on September 20, 2012 http://qje.oxfordjournals.org/ Downloaded from