The Power of Asking: How Communication Affects Selfishness, Empathy, and Altruism

26 Pages·2010·0.55 MB·English

The Power of Asking: How Communication Affects Selfishness,
Empathy, and Altruism∗
JamesAndreoni1 JustinM.Rao2
1DepartmentofEconomics,UniversityofCalifornia,SanDiegoandNBER
2Yahoo! ResearchLabs,SantaClara,CA
December15,2010
Abstract
Tounderstandthe“pure”incentivesofaltruism,economiclaboratoryresearchonhumansalmostal-
waysforbidscommunicationbetweensubjects. Inreality,however,altruismusuallyrequiresinteraction
between givers and receivers, which clearly must influence choices. Charities, for example, speak of
the “power of asking.” Indeed, evolutionary theories of altruism are built on human sociality. We ex-
perimentallyexaminecommunicationinwhichonesubjectallocates$10betweenherselfandareceiver,
and systematically altered who in the pair could speak. We found that any time the recipient spoke,
givingincreased–askingispowerful. Butwhenonlyallocatorscouldspeak,choicesweresignificantly
moreselfishthananyothercondition. Whenempathywasheightenedbyputtingallocators“inthere-
ceivers shoes,” giving appeared as if recipients had been able to ask, even when they were silent. We
concludethatcommunicationdramaticallyinfluencesaltruisticbehavior,andappearstolargelyworkby
heighteningempathy.
∗WewouldliketosendthankstoBenCowanandMeganRitzforresearchassistance,toSusanHenning,WilliamHarbaugh,
ZackGrossmanandtwoanonymousrefereesforusefulcomments,andtotheNationalScienceFoundation(SES0962484)andthe
ScienceofGenerosityInitiativeforgenerousfinancialsupport.
1
1 Introduction
Laboratoryexperimentsonaltruisticbehaviorhavealmostexclusivelystudiedsubjectsinisolationfrom
socialinteractioninordertoprotectanonymityandidentify“pure”incentivestogive. Yetintherealworld
givingoccursinthecontextofasocialinteractionbetweengiverandreceiverandtheincentivestogiveare
affected by the social factors surrounding this interaction. A common finding is that most subjects exhibit
significantaltruismandinequityaversion(FehrandSchmidt,1999;BoltonandOckenfels,2000;Andreoni
and Miller, 2002). Recent work has linked these preferences to brain activity (in areas associated with
rewards)arguinginfavorof“hardwiredegalitarianism”(Tricomietal.,2010). However,intheUnitedStates
andotherindustrializedcountriesthereisvastinequalityinconsumption,whilecharitablegivingisonly1-
2% of income (Andreoni, 2006). How can we reconcile a taste for equality with behavior that indicates
people generally tolerate a great deal of inequality in their daily lives? In this paper we argue that while
humansdohaveastrongcapacitytobehavealtruistically,selfishnesstypicallypredominates. Furthermore,
social cues have evolved so that altruistic behavior is not expressed indiscriminately, but rather is likely to
beexpressedwhenitisinstrumentalinservingotherselfish(orimperfectlyaltruistic)ends.
To test this hypothesis, we use a subtle manipulation of a single social factor: verbal communication.
Communication is a natural social cue because it forms the backbone of the interaction between giver and
receiver. Indeedaleadingtheoryontheoriginsofverbalcommunicationisthatitaroseoutofgesturalcom-
municationtofacilitatemutuallybeneficialcoordinativeacts(Grice,1957;Tomasello,2008). Furthermore,
verbal communication typically entails recursive belief formation about the subject matter and language
conventions. In Experiment 1 of our study, we used the Dictator Game (DG) and systematically altered
whointhepair(one,bothandtheorder)couldsendamessage. Wefindthatintheconditioninwhichonly
the allocator could speak, only 6% of the endowment was donated, which was significantly lower than the
no-communicationbaselineof15%. Thisistheconditioninwhichrolesweremostasymmetricinthesocial
interaction. In stark contrast, anytime the recipient spoke, at least 24% of the endowment was passed —
asking is indeed powerful. Interestingly, giving was highest in the conditions that involved two-way com-
munication. Intheseconditions30%oftheendowmentwaspassedonaverage,evenwhentheallocatorwas
firsttospeak.
Tohelpunderstandverbalexpressionandmotivations,third-partyreviewersperformedtextualanalysis.
We find that content of the messages from allocators significantly depended on the presence of an “ask.”
For instance, fairness was significantly more likely to be spoken about in the presence of an ask, whereas
luckwassignificantlylesslikely. Interestingly,thecontentdidnotdifferbasedonwhethertheallocatorwas
responding directly to an ask, or sending a message knowing they would receive a reply before they made
theirfinalallocationdecision. Inthelatterconditionallocatorsdidagoodjobof“anticipatingtheask”(the
modal ask focused on fairness and equal division) and tailored their message appropriately. Conversely, in
theone-waycommunicationconditioninwhichonlyallocatorsspoke,messageswereone-sixthaslikelyto
mentionfairnessandtypicallyofferedanapology.
The results of Experiment 1 are stark. When only the allocator could speak, he typically was very
selfish and issued a hollow apology, but the apologetic “blocking mechanism” was not employed in the
2
presence of an ask; in this case allocators’ messages displayed more of an understanding of the other’s
position. Thisfinding,alongwithrecentfindingsintheneuroeconomicsliteraturelinkingareasofthebrain
associatedwithcommunicationandsocialcontextswithempathicconcern(DeVignemontandSinger,2006;
Decety and Jackson, 2006; Moll et al., 2006; Hare et al., 2010) led us to hypothesize that communication
fromarecipientfacilitatesaltruismthroughfeelingsofempathy. InExperiment2empathywasheightened
by putting allocators “in the receivers shoes.” Experiment 2 used modified version of the two conditions
involving one-way communication in Experiment 1. Before roles were determined, all subjects filled out
a decision form for each role. Then roles were randomly determined and unused decision forms were set
aside. Intheconditioninwhichonlytheallocatorcouldspeak,theallocationsandverbalcontentappeared
asifrecipientshadbeenabletoask. Makingchoicesfromthepositionofbothrolesandbeingsubjectedto
averbalrequestledtonearlyidenticalpassdistributions. Ourinterpretationisthataskingleadstheallocator
the actively consider and identify with the role of the recipient; we call this feeling “empathy.”1 However,
there are limits in terms of the associated effects on giving. In both experiments, requests for more than
equaldivision(“selfishrequests”)leadtoaveragepasslevelssignificantlybelowthebaseline.2
There is considerable evidence that feelings of empathy are strongly connected to altruistic and pro-
social behavior (Batson et al., 1988; Batson, 2002; De Vignemont and Singer, 2006; Preston and de Waal,
2002). The “empathy-altruism hypothesis” posits that feelings of empathy are the primary explanation for
altruistic acts for which the agent does not expect to receive compensating material benefits through reci-
procityortheabsenceofsanctions. Laboratoryexperimentshavefoundthataltruisticbehaviorispromoted
through the reduction of social distance (Roth, 1995; Hoffman et al., 1996; Bohnet and Frey, 1999) and
makingpotentialvictimsofselfishnessmoreidentifiable(Schelling,1968;SmallandLoewenstein,2003).3
However, recent work has argued that selfish concerns such as guilt aversion (Charness and Dufwenberg,
2006;BattigalliandDufwenberg,2007)andself-imagemaintenancethroughself-signaling(BodnerandPr-
elec,2003)andself-deception(Danaetal.,2007)canhelpexplainseeminglyaltruisticbehavior. Although
theideahasnotreceivedexplicitattentionintheliterature,itindeedmaybethecasethatempathyoperates
through these channels. For example, it may raise the cost of self-deception.4 In Section 4 we discuss this
possibility.
Given the economic and social importance of altruistic behavior, several theories have been proposed
to explain the origins and evolution of altruism and cooperation in humans. Leading theories include kin
selection (Hamilton, 1964), reciprocity (Nowak and Sigmund, 2005; Trivers, 1971) and norm adherence
throughsanctions(BoydandRicherson,1992;DeQuervainetal.,2004;Gurerketal.,2006). Thesetheories
provide a sound theoretical backbone for the existence of altruistic behavior in the human psychological
composition and can help explain why people are often generous in situations in which the conditions of
the theories are not met (e.g. acts of altruism towards non-kin, in the absence of reciprocity/sanctions or
1Inaformalmodel,onecoulddefineempathyasinverselyproportionaltothevarianceofone’sbeliefaboutanother’sexpecta-
tions.
2Rankin(2006)alsofindsthisresultfornumericalrequests.
3Laboratoryworkhasalsodemonstratedthataltruisticbehaviorcanbeelicitedthroughself-interestrelatedchannels. Exam-
plesincludemonetaryrewards/punishment(Gurerketal.,2006;FehrandFischbacher,2003),emotion-basedrewards/punishment
(Mascletetal.,2003)andappealingtosubjects’desiretomaintainapositivesocialimage(AndreoniandBernheim,2009).
4Wethankarefereeandeditorforthishelpfulsuggestion.
3
one-timegiftstostrangers). However,theyrelyintwoimportantwaysonthefactthathumansareasocial
species. First, the social nature of human interaction allows for the underlying theoretical mechanisms to
function (for instance communication allows for reputation building and reciprocity). Tomasello (2008)
shows that the differences in altruism between great apes (which exhibit effectively no pure altruism) and
humans can be linked to humans’ advanced social capacities such as verbal communication. Secondly, the
theories rely on humans to respond to social cues so that they are not indiscriminately altruistic and hence
perishquickly.
Neuroimaging studies provide support for both points. The evidence indicates that the human brain
is wired so that the decision processes underlying altruistic behavior and socialization are strongly linked
(Harbaughetal.,2007;Molletal.,2006;Hareetal.,2001). Inadditiontotheneuralevidence,thereasoning
underlyingourargumentthatcommunicationaffectsempathyandelicitsaltruismrestsonauniquefeature
ofhumancommunicationknownas“recursivemindreading”or“roleimitationreversal”(Hareetal.,2001;
Akhtar et al., 1996). That is, in any dyad, person 1’s communicative acts depend critically on 1’s beliefs
concerning person 2’s beliefs and 2s beliefs about 1s beliefs, and so on. In economics, this is the familiar
notion of iterative belief formation, which underlies game theoretic solution concepts.5 This recursively
structured belief formation helps establish the “joint attentional frame” necessary for effective, high level
communication(Clark,1992).
InExperiment1,communicationfromrecipients,regardlessoftheorderofwhospoke,ledtoa“conver-
sation”morelikelytobecenteredaroundfairnessandmoregenerousbehavior. Thisissurprisinginthatthe
contentofrequestsisquitepredictable;onewouldpresumablyexpectamessagecenteraroundfairnessand
a numerical request for equal division and this is exactly the modal message. Despite the predictability of
therequest,allocatorsintheconditioninwhichonlytheygottospeakbehavedmoreselfishlythanthebase-
lineandsentmessagescenteredaroundluckorapology—“askingfortheobvious”matters. Experiment2
indicatesthatitmattersthroughtheelicitationofempathyassociatedwiththebeliefformationnecessaryfor
communication. Inthediscussionsectionweexplorethepossibilitythatempathyaffectsbehaviorthrough
self-interestedchannelssuchasguiltaversionandself-deception.
The remainder of the paper proceeds as follows: Section 2 presents the experimental design, Section 3
providestheresults,Section4containsadiscussionandSection5concludes.
2 Experimental Design
In order to test our hypothesis that verbal communication has evolved to mediate the expression of
altruism,wemanipulatedthecommunicationavailabletosubjectsplayingamodifiedversionofthedictator
game(DG).TheDGisregardedasthestandarddecisiontasktostudyaltruisminexperimentaleconomics
(Forsytheetal., 1994; AndreoniandMiller, 2002). Inthebaselineversionofthegame, twosubjectsshare
100moneyunits(MUs). MUsarealwaysworth$0.10toallsubjects. Onesubjectisrandomlyassignedthe
roleofallocatorandtheotherisassignedtheroleofreceiver. Theallocatorinitiallyholdsall100MUsand
5Infact,behavioralmodelsofboundedrationality,suchaslevel-kthinking,arriveatnewequilibriabylimitingthenumberof
iterativesteps,seeforinstanceCrawfordandIriberri(2007).
4
Figure1: Decisionforminwhichtherecipientfirstsentrequest(AskorAskthenExplain)
makes the decision of how many MUs pass to the receiver, without communication between subjects. The
allocator’sdecisionisfinalandcompletelydeterminesmonetarypayoffs.
We conducted two experiments building on the baseline DG without communication. Experiment 1
included238subjectswhoplayedtworoundsoftheDGwithdifferentanonymouspartners. Rolesremained
constantacrossrounds. InadditiontothebaselineDGwerefourconditionsthatallowedsubjects,tovarying
degrees, tocommunicate via writtenverbal and numericalmessages. Communication wasalways optional
andfreeform.
In condition “Ask”’ (A), the receiver wrote a verbal message along with a numerical “pass request,”
which the allocator read before making the pass decision. After the allocator made the pass decision the
receiver was informed of the payoffs for the game. In “Explain” (E), the allocator sent a written verbal
message along with the pass decision, however the receiver stayed silent. In “Ask then Explain” (AE), the
receiver first sent a verbal message and numerical request and then the allocator recorded the pass choice
accompaniedbyaverbalreplymessage. In“ExplainthenAsk”(EA)theallocatorfirstsentaverbalmessage
alongwitha“non-bindingallocation,”thereceiverthenrespondedwithaverbalandnumericalrequest,after
whichtheallocatordeterminedfinalpayoffs. Thebreakdownofsubjectsacrossconditionwas: Baseline40,
A40,E40,AE80andEA38.
Thesubjectswerenotgivenanysuggestionsregardingthecontentofthemessages;theonlyrestriction
prohibited the inclusion of identifying information or promises external to the laboratory. Anonymity was
maintainedinordertoidentifytheeffectofcommunicationwithoutconfoundingfactors,suchasreputation
outsideoftheexperiment, whichareknowntoinfluencebehaviorintheDG(Roth, 1995). Allinstructions
areavailableintheappendix. Figure1providesanexampledecisionform.
Our secondary hypothesis is that communication from the recipient leads the allocator to consider the
recipient’s position more fully and this empathic consideration induces altruistic behavior. To directly test
5
this hypothesis, Experiment 2 used augmented versions of A and E in which feelings of empathy were
intentionally heightened. Before roles were determined, all subjects filled out decision forms for the first
stage of both the A and E versions of the DG. One form (E) placed the subject in the role of allocator and
theother(A)theroleofreceiver. Foreachversion,thesubjectswereassigneddifferentcounterpartsandwe
madethiscleartothesubjectsintheinstructions. Theintentwastoleadthesubjectsto“putthemselvesin
theother’sshoes,”whilemaintainingone-waycommunication. AftertheStage1decisionsweremade,role
were randomly determined and we set aside the A forms from allocators and E forms from receivers. The
remaining forms were then used to determine monetary payoffs. 40 subjects played a single round in this
manner. Itisimportanttonotethatdespitefillingoutdecisionsforeachrole, eachsubjectplayedonlyone
role,whichalwaysinvolvedone-waycommunication.
3 Results
Experiment1Results
Figure2presentsmeanamountspassedinExperiment1(panelA)andthefractionofallpassamounts
equaltozeroandtoequaldivisionontheright(panelB).Theevidenceisclear. Boththeexistenceandstruc-
ture of communication significantly influenced allocators’ expressed altruism. In the no-communication
baseline, allocators passed an average of 15.3 MUs. In E, allocators gave significantly less than the base-
line (Wilcoxon rank-sum z = −2.73, p < 0.006), chose fewer equal divisions (t = −2.33, p < 0.025,
two-tailedt-test, standarderrorsclusteredbysubject)andmorezeros(p < 0.007). Conversely, inthetwo-
way communication conditions (AE, EA) allocators’ transfer greatly exceeded the baseline (AE: z = 3.29,
p < 0.001,EA:z = 2.04,p < 0.041). GivinginAwashigherthanthebaselineandthedifferencebecomes
significant when we only consider requests for an even division or less (z = 1.965, p < 0.049). A full
comparisonofconditionsisgiveninAppendixTable2.
In the conditions in which allocators “spoke” first, giving was very much a function of whether the
communication was one-way (E) or two-way (AE, EA). Passes were on average over four and half times
higher in EA than in E (EA mean= 27.0, E mean= 6.5; z = 4.28, p < 0.0001), while equal division was
tentimesmorelikely(t = 3.69,p < 0.0004). Infact,themeanofthenon-bindingallocationfromthefirst
roundofcommunicationinEAwas25.8,farexceedingthemeanpassinE(z = 4.41,p < 0.0001).6
Table 1 examines whether the content of subjects’ written communication was associated with pass
behavior. Each message was evaluated for content by seven undergraduate reviewers (gender balanced to
match the subject pool) who had no prior knowledge of the study. The communication items are intended
tocapturethebasiccontentofamessage. Amessagecanfallintomorethanonecategory,ornoneatall. In
amajorityofcases, revieweropinionwasunanimous. Intheremainingcases, theaverageratingwasused.
Theinstructionstoreviewersarecontainedintheappendix.
ThestatisticaltestsinTable1comparecommunicationinthetwo-wayconditionstotheirone-waycoun-
terpart. Overall,allocatorcommunicationvariedinwaysconsistentwiththeexpressedaltruism. Allocators
6Although the meansof the non-binding and finalallocation in EA are not significantlydifferent from each other, there isa
significantmajorityofsubjectsshadedslightlyup.
6
Figure 2: (A) Means of pass value by Experiment 1 condition: Baseline (no communication), A (ask by
recipients), E (explain by givers), AE (ask then explain), EA (explain then ask). (B) Fraction of equal
divisions and pass = 0 by condition of Experiment 1. The allocator determined the final allocation of 100
MUs between themselves and an anonymous partner (the receiver) by “passing” any value between 0 and
100MUs. Barsgive+/−2s.e.
in EA and AE were more likely to express fairness and less likely to express remorse than allocators in
E. These differences are large in magnitude and highly significant. Receivers’ written messages (requests)
variedbyconditionaswell,whilethenumericalrequestdidnot. Receiversweresignificantlylesslikelyto
communicate flattery and acknowledge the allocator’s power in the two-way conditions. These differences
are most likely due to the more balanced nature of two-way communication. Unsurprisingly, the modal
request in all conditions expressed fairness and called for an equal division. Also, the likelihood of using
verbalcommunicationatallwassignificantlyhigherinthetwo-wayconditions.
Acrossconditions,allocatorswhoexpressedfairnessbehavedfarmorealtruistically(n = 48,meanpass
= 40.21) than those who did not (n = 110, mean = 16.04, t = 7.20, p < 0.000). Conversely, remorse
was associated with far lower pass values (n = 45, mean = 10.42, vs. n = 45, mean = 28.54, t = 4.93,
p < 0.000). Conditional on the numerical request, the content of the request, as measured through the
communicationcategoriespresentedinTable1,didnotsignificantlyaffectallocatorbehavior. Thequantile
regressionusedtosupportthisconclusioniscontainedintheappendix. Theestimatedcoefficientonfairness
waswellwithinastandarderrorofzero(coeff. −3.83,t = 0.32,p < 0.75);therewassufficientvariationto
estimatethiscoefficientas61.6%ofsubjectsrequestinganequaldivisionmentionedfairness.7 Noneofthe
othercategoriesapproachedstandardsignificancelevelsasallwerewellwithinonestandarderrorofzero.
Perhapsparadoxically,thewordsthemselvesinrequestsdonotappeartodirectlyaffectallocatorbehavior,
buttheexistenceofarequestmatterstremendously.8
7Includingatermforfairnessinteractedwiththeleveloftherequestyieldsacoefficientestimationof0.81,notsignificantly
differentfrom0.
8Rankin(2006)findsthatnumericalrequestsincreasepassesinananonymousDG,butactuallyreducepasseswhentheinter-
7
Table1: CommunicationContentbyConditionofExperiment1
Condition
A E AE EA
FractionofExplainMessagesContaining:
Remorse 0.39 0.14∗∗∗ 0.05∗∗∗
Fairness 0.03 0.23∗∗∗ 0.13∗
Need 0.13 0.06 0.04∗
Luck 0.07 0.06 0.05
You’ddoittoo 0.08 0.02 0.00∗
Nowords 0.18 0.05∗∗ 0.00∗∗∗
Non-bindingallocationinExplain-Ask 25.8
FractionofAskMessagesContaining:
Fairness 0.45 0.53 0.34
FriendlyGreeting 0.23 0.16* 0.17
Flattery 0.28 0.08∗∗∗ 0.06∗∗∗
AcknowledgePower 0.26 0.20 0.09∗∗∗
Need 0.19 0.14 0.12
Nowords 0.10 0.03∗ 0.00∗∗
NumericalRequestinAsk 50.4 49.8 45.9
∗∗∗p<0.01,∗p<0.1indicatetwo-tailedsignificanceascomparedto
one-waycommunicationgivenbyatwo-tailedt-test
Figure 3: Bars: Frequency of pass requests (right axis), Line: L.A.D. fitted pass values as a function of
numericalrequest(leftaxis),Diamonds: Meanpassvaluesforrelativelyfrequentrequests(leftaxis)
8
Table2: DoYouGetWhatYouAskFor?
RequestCategory
r < 40 40 ≤ r ≤ 45 r = 50 r > 50
Probabilityofpass< r 0.50 0.74 0.58 0.95∗∗∗
Meanpass 5.0 16.5 18.4 11.4
Probabilityofpass= r 0.13∗∗ 0.15∗∗ 0.39 0.05∗∗∗
Meanpass 15.0 40.0 50.0 80.0
Probabilityofpass> r 0.38∗∗∗ 0.11 0.03 0.00
Meanpass 47.5 50.0 85.0 n/a
%ofRequests 10.2% 17.3% 59.0% 13.5%
AggregateMean 22.19* 23.7** 32.9 14.7∗∗∗
∗∗∗p<.01,∗∗p<.05,∗p<.10two-tailedsignificance
ascomparedtor=50,givenbyat-test
Numerical request had a significant effect (coeff. 1.00, t = 3.76, p < 0.000), but asking for more
than equal division was costly (coeff. −1.25, t = −3.02, p < 0.001). Table 2 shows why this is the case
and the result is illustrated graphically in Figure 3. Subjects rarely got more than they asked for, with the
exception being requests for quite low amounts and these requests comprise only 10.2% of all requests.
Across conditions, 15% of requests for 40 were granted and 11% were exceeded. Of these passes that
exceeded 40, the mean was 50. In contrast, 39% of requests for 50 were granted. The difference 39%
vs. 11% of subjects receiving 50 across these two requests is highly significant (t = 2.79, p < 0.006)
– asking is indeed powerful. However, asking for more than an equal division was detrimental; only 5%
of such requests were granted and none were exceeded. The mean pass for these “selfish requests” was
less than half of the mean for the modal request of equal division and less than the mean in the baseline
no-communicationcondition.
Experiment2Results: EmpathyasaProximateFactor
The patterns of communication content (Table 1) provide evidence that the positive effect of two-way
communicationonaltruisticbehaviorismediatedbyfeelingsofempathy.9 Experiment2teststhishypoth-
esis directly by using one-way communication and intentionally heightening feelings of empathy towards
one’s partner (and this is common knowledge). Fig. 4A presents mean pass by condition of Experiment
2. The mean pass of “E with empathy” (E(e)) was 21.7, which is significantly higher than E (z = 4.03,
p < 0.0001). The mean pass of “A with empathy” (A(e)), was 27.6, which was greater than A, although
actionisface-to-face.Hearguesthattherequestscancrowd-outpro-socialmotivationpresentintheface-to-facetreatment.Inour
experiment,itispossiblethatmentioningthenumericalrequestscrowdedoutthecontentofverbalcommunication.
9Note that we are only claiming this is altruistic behavior, not pure altruism. This leaves open the possibility that although
empathyisaproximatefactor,itismediatedthroughselfishchannels,suchasself-deceptionorguiltaversion. Weaddressthese
pointsindetailinSection4.
9
Figure 4: (A) Means of pass value by Experiment 2 condition: A(e) (A with experimentally heightened
empathy) and E(e) (E with experimentally heightened empathy). (B) Fraction of equal divisions and pass
= 0inconditionsinwhichallocators“spoke”first. (C)Pooledcomparisonofthetwo-waycommunication
in Experiment 1 and the “empathy” conditions of Experiment 2. Statistical tests given in Tables 1 and 3
fail to reject equality in distribution of pass value in AE and EA of Experiment 1 and A(e) and E(e) in
Experiment2. Barsgive+/−2s.e.
not significantly (z = 0.79, p < 0.42) and very close to the generous behavior observed in the two-way
conditions of Experiment 1 (EA = 27.0, AE = 30.2). As hypothesized, the selfish behavior exhibited in E
waseliminatedwiththeheightenedempathy,justasitwaswiththeexistenceofasubsequentrequestinEA.
This is shown in Fig. 4B, which compares the fraction of equal divisions and zeros in all the conditions in
whichallocatorsspokefirst.
Subjects exhibited significantly more generosity in both Experiment 2 conditions as compared to the
baselineinExperiment1,regardlessofthefacttheybothinvolvedone-waycommunication(A(e)z = 1.85,
p < .032; E(e) z = 1.45, p < 0.073 one-tailed t-test).10 Most interestingly, the distribution of choices in
theempathy-inducingconditionsinExperiment2werenearlyidenticaltothetruetwo-waycommunication
conditionsofExperiment1. ThisisdisplayedgraphicallyinFig. 4C,whichcomparesthepooleddistribution
ofEA&AEtoE(e)&A(e)(withineachpooltheconditionsarenotsignificantlydifferentfromeachother).
Thedistributionsarevirtuallyidentical.
10We use a one-tailed test here due to the bulk of evidence from the psychology literature that empathy increases observed
generosity(Batsonetal.,1988;Batson,1991;PrestonanddeWaal,2002).
10