《实验经济学》课程教学资源（参考文献）Testing for Altruism and SocialPressure in Charitable Giving.pdf_大学文库

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 doorto-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 Business, 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 Alexander, 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 90%ofindividuals 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 An rica capital eve 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 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 pressu to giv Such rather avoid the persona interaction with the solicitor.The two motivations have very different welfare implications.The altruism(or warm glow)model (Becker 1974:Andreoni 1989,1990)posits that giving is mostly ,and that it is utility del.dor maximizing for the giver to give.Under this tio amb ously 1m hance the giver's ty as w as so eta are. 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,un olicited donation reque sts.Building on a theore ical model,we design a field experiment that allows us to test 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. ation allows us to de ecompose the share of giving that is du altruism versus social pressure and to quantitatively evaluate th welfare effects for the giver.In this wav.the empirics and theorv 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 st actural estim ates of welfare implications sof a field experiment.Moreover,while 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

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 motivations. 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 estimation 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 raising drive for two charities,a loc childr '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 eithe seek or avoid the solicitor In our first treatment,a flyer on the doorknob notifie 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 these two to a baselin eatment ,whe approa ouseholds in the usual without fyer. 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- main of giv the flyer should i se both the e pr me an giving Beca se giving is anc ng,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 P essure the main dri of givin the flyer should lo wer both the frequenc of opening the door and the frequency of giving.Since being askec to give is welfare-diminishing.potential givers should sort out of opening the door and should not give via Internet or check because these forms of donation are not subject to social pressure. 2 We report four main results,which are similar r across the two charities yer. ver the frequency of op the 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 giv the Aver with ar opt -out checkbox de ing.How giv by 28%relati to a baseline of 7%for the local charity and 4 tive to a 59 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

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 3 Our field experiment revolves around a door-to-door fundraising drive for two charities, a local children’s hospital, which has a reputation as a premier hospital for children, and an outof-state charity, unfamiliar to most solicitees. Between April and October 2008, we approached 7,668 households in the towns surrounding 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) altruismversus 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 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 pr ssure e are important determinants of giving in s settin with stron er evid e for the ro 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 nd social celin each other out.The de e m flyer with opt 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 pres than large d socia pressure interpretation is als 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 all donations de e,not la rge donations Se individual might donate to send(costly)signals to the selves or to others that they are generous (Bodner and prelec 2003:Ben 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 ation,he ev er,is le onsis nt with the fact that 12% households he opt out treatm at check th ut box hicl 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 pr nciple These potential donors,how er,when alerted ofa mpa by a fyer, uld seek alternat ve wa s 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 with complementary field experiments on the value of time, run in the same geographical as in 2008 and 2009 Thes

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 altruism 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 receiving 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 optout 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; Benabou 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 estimate the model parameters. We combine data from the treatments 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 parameter in the fund- ng tre atments,the se sitivity of home pre 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 surveys are announced(with a flyer.with or without opt-out option).Higher payments and shorter duration increase the nce at home up to169% and increase survey completion by 178 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 ng the door ing different a survey,and optin Key parame ers are altruists the curvature of the altruism function,and I 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 g due to altr cave in the nt gi en,with on ao pr dicted don above $50 h 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 charity.As a result of social pressure.a maiority of donors give more than they would have liked to.Half of donors derive negative utility fron 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 hv$110 per household contacted for the in-state charity and by$0.44f th out-ofst cha rity. The ative welfar 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 ou r fund-raising campaigns to be repr ntative of door-to-door solicitat 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

TESTING FOR ALTRUISM AND SOCIAL PRESSURE 5 experiments aredesignedtoestimateakeyparameterinthefundraising 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 probabilities 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 warmglow 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 outof-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 campaigns 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 m rginal,as opposed to infr not' marginal,giving.House. holds that do give to and-ra social pressure,lil give 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 mistake to ignor e the high-pr sure reque sts studie e that the motives for fra-marginal g giving studied in the literature apply.Small capital campaigns,like the one studied in this article,are common and reveal 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 charitie s.However,they also sug gest an alter ative:providing hous olds with the opportu 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 altruistic givers,who give larger amounts is likely to counte rbalance the sorting out of givers motivated by social pres no give sm ller 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 underlving parameters.which is surprisingly rare.Of all field experiments published in top (Card,Del five nals from 1985t02010 Vigna,and Malmendic r2011 this featur small 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 eral other rides field evidence nds of literature.It t social t complemen (Fehr and Gachter 2000;Charn ss ano 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 Meie .2009: Croson and Sha

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 reasons for marginal, as opposed to infra-marginal, giving. Households 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 inframarginal 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 donot-solicit or do-not-call list for charities. However, they also suggest 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 e on social pressure(Asch 1 51;Milgram 1963;Gari ano,Palaci uerta and Prendergast 2005;Gerber,Green,and Larimer 2008;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 ressure.We introduce the expe ntal design in Section 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 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 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 edictio ns.The technical details,including 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 e denote the potential giver, solicitee ply as giver.In the fir stage,tr give may receiv 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 ∈(o,1).fshe I the f ye she st the y to h 0,1]at a cost c(h), with )=0,c(ho)=0,an c"(.)>0.That is,the marginal cost of small adjustments is small but larger adjustments have an increasingly large cost.We do not require symmetry around ho and we allow for corner solutions at h=0orh=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+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