《实验经济学》课程教学资源（参考文献）Testing for Altruism and Social Pressure in Charitable Giving.pdf_P6-P10

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 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 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 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 < 1. Thecharitytherefore receives θgm. 1 The private utility satisfies standard properties: u0 ( ∙ ) > 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, impure 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, and limg→∞ v0 (g, ∙) = 0. The parameter a ≥ 0 denotes the level of altruism,3 and the overall utility from giving is av (G−i + g + θgm). In the case of impure altruism, the agent cares about the warm glowfrom giving g. Hence, v (∙) does not necessarily depend on the giving of others, G−i, and a ≥ 0 captures the intensity of the warm glow. We make the same assumptions v0 g > 0, v00 g,g < 0, and limg→∞ v0 (g, ∙) = 0.4 Finally, in the case of spite towards the charity, the agent dislikes givingtothecharity. Theutilityis av (G−i + g + θgm), with a < 0 capturing the intensity of spite. It is natural toassume that the disutility of giving increases with the donation in a convex 1. The key results generalize to a fixed cost of giving by mail, but the algebra is more complex. 2. We allow for giving to exceed current wealth, that is, the case g + gm > 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(spite); it is concave in the first case and convex in the second.When the distinction is important,we use v'to denote the function for a >0,v-to denote the function for a <0,and v to denote the function that equals v fo ≥0andv-fora<0.Not ce that it is important to consider the case of spite because,unlike in a standard model of giving,even spiteful individuals may give to the charity if social pressure is high enough. The third element in the utility function is social pressure The giver pays a utility costs(g) S.g- <g o for not giving or only a giv 11 ng sm mount wh hile the present.The cost is highest for the case of no donation(s(0)- Sg) then decreases linearly in g,and is 0 for donations ofg or higher. The giver does not incur a social pressure cost if she is away from home during the visit.The special case of S=0(no social del arm glow)represe ents the ssum tha the giver is aware of h own preferences and rationally anticipates her response to social pressure. Giving in Person.We solve the model working backward.In the second stage,conditional on being at home and answering the door,the giver choosesg to maximize(1).Notice that conditional on ans e giver always er involve an a dditional cost (1-0) and do not eliminate the social pressure cost. We characterize optimal givingg*as a function of the param eters a and S in Lemma 1A in the Appendix.(The thresholds a(S),a(S),and a are also defined in the Appendix.)Figure I trates th he case of linear privat e ut tility uand()= 0) which are the assumptions used for the structural estimation. Giving g increases in altruism.When altruism is sufficiently mount,buta ))the individual does not give.For a higher level a(S)),the individual gives a positive th or eve ghe】 altruism S a there is bunching at g*=g,which is the lowes level of giving associated with zero social pressure cost.Finally,for large enough a (aa),the donor gives more than g".Any giving above g*is due to altruism (hence the threshold 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 < 0 (spite); it is concave in the first case and convex in the second. When the distinction is important, we use v+ to denote the function for a ≥ 0, v− to denote the function for a < 0, and v to denote the function that equals v+ for a ≥ 0 and v− for a < 0. Notice that it is important to consider the case of spite because, unlike in a standard model of giving, even spiteful individuals may give to the charity if social pressure is high enough. The third element in the utility function is social pressure. The giver pays a utility cost s(g) = S ∙ (gs − g) ∙ 1g<gs ≥ 0 for not giving or only a giving small amount g while the solicitor is present. The cost is highest for the case of nodonation (s(0)=Sgs ), then decreases linearly in g, and is 0 for donations of gs or higher. The giver does not incur a social pressure cost if she is away from home during the visit. The special case of S = 0 (no social pressure) and a = 0 (no altruism or warm glow) represents the standard model. We further assume that the giver is aware of her own preferences and rationally anticipates her response to social pressure. Giving in Person. We solve the model working backward. In the second stage, conditional on being at home and answering the door, the giver chooses g to maximize (1). Notice that conditional on answering the door, the giver always prefers to donate in person because mail donations involve an additional cost (1 − θ) and do not eliminate the social pressure cost. We characterize optimal giving g∗ as a function of the parameters a and S in Lemma 1A in the Appendix. (The thresholds a(S), a(S), and aˉ are also defined in the Appendix.) Figure I illustrates the case of linear private utility u and v+0 (0) = v−0 (0), which are the assumptions used for the structural estimation. Giving g∗ increases in altruism. When altruism is sufficiently low (a ≤ a (S)), the individual does not give. For a higher level of altruism (a (S) < a < a (S)), the individual gives a positive amount, but less thangs . Forevenhigheraltruism(a (S) ≤ a ≤ aˉ), there is bunching at g∗ = gs , which is the lowest level of giving associatedwith zerosocial pressure cost. Finally, for large enough a (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