'Sharing Responsibility with a Machine'Latane and Nida, 1981) as well as the perceived guilt (see...

Sharing Responsibility with a Machine∗

Oliver Kirchkamp†, Christina Strobel‡

October 4, 2017

Humans make decisions jointly with others. �ey share responsibility for theoutcome with their interaction partners. More and more o�en the partner in adecision is not another human but, instead, a machine. Here we ask whether thetype of the partner, machine or human, a�ects our responsibility, our perceptionof the choice and the choice itself. As a workhorse we use a modi�ed dictatorgame with two joint decision makers: either two humans or one human and onemachine.

We �nd a strong treatment e�ect on perceived responsibility. We do, however,�nd only a small and insigni�cant e�ect on actual choices.

Keywords: Experiment, Dictator Game, Human-Machine Interaction, Hybrid-Decision Situ-ation

∗�is document has been generated on October 4, 2017, with R version 3.3.3 (2017-03-06), on x86 64-pc-linux-gnu. We thank the Max Planck Society for �nancial support through the International Max PlanckResearch School on Adapting Behavior in a Fundamentally Uncertain World. We also thank the audienceof IMPRS doctoral seminars for their input. Data and methods are available at https://www.kirchkamp.de/research/shareMachine.html.

†FSU Jena, School of Economics, Carl-Zeiss-Str. 3, 07737 Jena, [email protected].‡FSU Jena, School of Economics, Bachstraße 18k, 07737 Jena, [email protected].

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https://www.kirchkamp.de/research/shareMachine.html


1. IntroductionIn almost all areas of life, it is increasingly true that decisions are the result of interactionsbetween humans and machines. We encounter automated systems no longer only in a sup-portive capacity but, more frequently, as systems that take actions on their own. For example,computer assisted driving services drive autonomously on roads and surgical systems con-duct surgeries independently.1 As a result, humans �nd themselves confronted with a newsituation: they have to share decisions with a machine. We call such a situation a hybriddecision situation. 2

In this paper we investigate human decision-making in a hybrid decision situation. Morespeci�cally, we investigate if sharing a decision with a computer instead of with anotherhuman has an in�uence on the perception of the situation and thus a�ects human decisions.Human decision-making in groups with other humans has been researched extensively andformer research has shown that the perceived personal responsibility (see Fischer et al., 2011;Latane and Nida, 1981) as well as the perceived guilt (see Ba�igalli and Dufwenberg, 2007;Rothenhausler et al., 2013) for an outcome is lower when a decision is shared. We also knowfrom studies in economics (see Engel, 2011; Luhan et al., 2009) and in social psychology (seeDarley and Latane, 1968; Wildschut et al., 2003) that humans behave more sel�shly if a deci-sion is shared. However, so far the literature has only focused on decisions shared betweenhumans. Here we ask whether humans also perceive themselves to be less responsible andguilty and behave more sel�shly when the decision is shared with a computer.

As a workhorse, we use a binary Dictator Game. We compare three treatments: a Dicta-tor Game with a single human dictator, a Dictator Game with two human dictators, and aDictator Game with one human dictator and a computer.

�e remainder of the paper is organized as follows: Section 2 provides a literature reviewfocusing on experimental evidence from economics and social psychological research. Weexpecially discuss the literature on individual behavior in groups as well as �ndings fromresearch on human-computer interactions. In Section 3 we present our experimental designand explain our treatments in more detail. Section 4 relates the experiment to the theoreticalbackground and derives behavioral predictions. Results are presented in Section 5. �e lastsection o�ers a discussion and some concluding remarks.

2. Review of the LiteratureIn Section 2.1 below we present former research on individual decision-making in groupsand and point out studies explaining why humans behave more sel�shly when deciding withother humans. �en, in Section 2.2, we turn to research on human-computer interactions andoutline what is already known about how machines are perceived and how humans behave

1See for example Choi et al. (2016), Seaman (2016), Senthilingam (2016) and Stone et al. (2016).2It is important to know that machines not always perform be�er than humans and are also susceptible to

errors. For example, according to an international survey 56.8% of 176 responding surgeons had experiencedan irrecoverable intraoperative malfunction of the robotic system during an urological surgery (Kaushiket al., 2010).

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towards them.

2.1. Shared Decision-Making with HumansPeople have to make decisions in situations where the overall outcome does not only de-pend on their own decisions but also on the decisions of others frequently. In a number ofexperimental games, such as the the Trust Game (Kugler et al., 2007), the Ultimatum Game(Bornstein and Yaniv, 1998), the Coordination Game (Bland and Nikiforakis, 2015), the Sig-naling Game (Cooper and Kagel, 2005), the Prisoners Dilemma (McGlynn et al., 2009), theGi� Exchange Game (Kocher and Su�er, 2007), the Public Good Games (Andreoni and Petrie,2004) as well as in lo�eries (Rockenbach et al., 2007) and Beauty Contests (Kocher and Su�er,2005; Su�er, 2005), people have been found to behave more sel�shly, less trustworthy andless altruistic toward an outsider when deciding together with others.

Even in a game as simple game as the Dictator Game, where one person – the dictator –decides how to split some endowment between herself and another person – the recipient –who has no say, people behave in a more strategic and sel�sh way when deciding in groupscompared to individual decision-making. For example, Dana et al. (2007) �nd that in a sit-uation where two dictators decide simultaneously and the sel�sh outcome is implementedonly if both dictators agree on it, 65% of all dictators choose the sel�sh option, while only26% of all dictators choose the sel�sh option when deciding alone. �is observation is con-�rmed by Luhan et al. (2009). In their experiment 23.4% of a dictator’s endowment is sent tothe recipient when the dictator decides alone but only 19% is sent to the recipient when thedictator acts as a members of a three-person team. Experiments in social psychology also�nd that people are less likely to help when others are around (Fischer et al., 2011) and giveless money as part of a group (Panchanathan et al., 2013).

Although experimental evidence shows that people behave more sel�shly in shared de-cisions, we do not know much about the driving forces behind it. Falk and Szech (2013)and Bartling et al. (2015) presume that individuals behave more sel�shly when deciding ingroups as the pivotality for the �nal outcome is di�used. �is di�usion lowers the individualdecisiveness for the �nal outcome and makes it easier to choose the self interested option.According to Ba�igalli and Dufwenberg (2007) human actions aim at reducing the feeling ofguilt caused by a decision. Building on this idea, Rothenhausler et al. (2013) conclude thatgroup-decisions allow to share the guilt for an individual decision and thus makes it easierto choose a sel�sh option in a group. �ere are also concepts in social psychology explain-ing more sel�sh decision-making in groups than in individual decision situations. AlreadyDarley and Latane (1968) propose the concept of di�usion of responsibility: sel�sh decisionsin groups are caused by the possibility to share the responsibility for the outcome amonggroup members. �is idea is con�rmed by several studies in social psychology showing thatpeople indeed tend to feel less responsible for the �nal outcome when they have to decidetogether with others (see Forsyth et al., 2002; Freeman et al., 1975; Latane and Nida, 1981;Wallach et al., 1964). Further possible mechanisms driving sel�sh decision-making in groupsare suggested by research on the so called interindividual-intergroup discontinuity e�ect, a ef-fect that describes the tendency of individuals to be more competitive and less cooperative ingroups than in one-on-one relations (see Insko et al., 1990; Meier and Hinsz, 2004; Wildschut

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et al., 2003). According to this research there are four moderators promoting sel�sh deci-sions in groups. First, the social-support-for-shared-self-interest hypothesis states that groupmembers can perceive an active support for a self-interested choice by other group members.Second, the identi�ability hypothesis proposes that deciding in groups provides a shield ofanonymity that could also drive sel�sh decision-making. �ird, according to the ingroup-favouring norm, decision makers could perceive some pressure to �rst bene�t the own groupbefore taking into account the interests of others. And �nally, the altruistic-rationalizationhypothesis suggest that deciding in a group enables individuals to justify their own sel�shbehavior by arguing that the other group members will also bene�t from it.

To sum up, more sel�sh decision-making in groups seems to be driven by (1) the di�usedpivotality for the decision, (2) a lower level of perceived responsibility and guilt for the out-come, (3) the increased anonymity of the decision and (4) the feeling that a sel�sh decisionalso favours the group and is supported or even demanded by the members of the group.

2.2. Perception of and Behavior towards ComputersA number of studies �nd that computers are treated in a way similar to humans. For instance,humans seem to respond socially to computers (Katagiri et al., 2001; Reeves and Nass, 2003),use social rules in addressing computer behavior (Nass et al., 1994), ascribe human-like at-tributes to computers (Nass and Moon, 2000), and accept computers as teammates (Nass et al.,1996). Moon and Nass (1998) even observe that humans have a tendency to blame a com-puter for failure and take the credit for success when they feel dissimilar to it while blamingthemselves for failure and crediting the computer for success when they feel similar to it. Inaddition, several studies �nd that computers are held at least partly responsible for actions(see Bechel, 1985; Friedman, 1995; Moon, 2003).

Although humans seem to treat computers and humans o�en in a similar way, di�erencesremain: Melo et al. (2016) �nd that recipients in a Dictator Game expect more money from amachines than from another human and dictators in a Ultimatum Game o�er more money toa human recipient in an Ultimatum Game than to an arti�cial counterpart. Furthermore, Meloet al. also show that people are more likely to perceive guilt when interacting with an humancounterpart than when interacting with machines. In addition, as a study by Gogoll and Uhl(2016) demonstrates, people seem to dislike the usage of computers in situations where adecisions also a�ect a third party. In the experiment people could delegate a decision in atrust game either to a human or to a computer algorithm that exactly resembles the humanbehavior in a previous trust game. Gogoll and Uhl observe that only 26.52% of all subjectsdelegate their decision to the computer while 73.48% delegated their decision to a human.Gogoll and Uhl also allowed impartial observers to reward or to punish actors conditional ontheir delegation decision. �ey �nd that, independent of the outcome, impartial observersreward delegations to a human more than delegation to a computer.

Consequently, especially in domains in which fundamental human properties such asmoral considerations and ethical norms are of importance, �ndings from human-human in-teractions can not necessarily be directly transferred to human-computer interactions, how-ever, while research in economics and social psychology analyses shared decision-makingbetween humans extensively there seems to be a gap when it comes to shared decision-

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making with arti�cial systems such as computers.

3. Experimental DesignWe implemented an experimental design with the following elements: (i) a binary DictatorGame in which people were able to choose between an equal and an unequal split, (ii) a ques-tionnaire to measure the preceived responsibility and guilt, and (iii) a manipulation check inwhich people were confronted with a counterfactual deciding situation. �e decision in thebinary Dictator Game was made either by a single human dictator (SDT), by two (multiple)human dictators (MDT), or by a computer together with a human dictator (CDT).

3.1. General ProceduresIn each experimental session, the following procedure was used: upon arrival at the labo-ratory participants were randomly seated and randomly assigned a role (Player X, Player Y,and, depending on the treatment, Player Z). All participants were informed that they wouldbe playing a game with one or two other participants in the room and that matching wouldbe random and anonymous. �ey were also told that all members of all groups would bepaid according to the choices made in that group. Payo�s were explained using a genericpayo� table. A short quiz ensured that the task and the payo� representation was under-stood. A�er the quiz the actual payo�s were shown to participants together with any otherrelevant information for the treatment. All treatments were one-shot dictator games with abinary choice between an equal and an unequal (welfare ine�cient) wealth allocation. A�ermaking the choice and before being informed about the �nal outcome subjects were askedto answer a questionnaire to determine their perceived level of responsibility and guilt. Ev-ery participant was paid privately on exiting the room. All experimental stimuli as well asinstructions were presented via a computer interface. We framed the game as neutrally aspossible, avoiding any loaded terms. Payo�s were displayed in Experimental Currency Units(ECU’s) with an exchange rate from 1 ECU equals 2 Euro. �e entire experiment was com-puterized using z-Tree (Fischbacher, 2007). All subjects were recruited via ORSEE (Greiner,2004).

3.2. TreatmentsWe had three di�erent treatments in total. One treatment, the so called “Single DictatorTreatment” or “SDT”, involved two players, one dictator and a recipient. Two more treat-ments involved three players, two dictators and one recipient. In one of these treatments,the so called “Multiple Dictator Treatment” or “MDT”, all players were humans. In the othertreatment, the so called “Computer Dictator Treatment” or “CDT”, the decision of one of thedictators was not made by him/herself but instead of by a computer. To compare the threedi�erent treatments We used a between subject design.

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3.2.1. Single Dictator Treatment

Payo�s for the Single Dictator Treatment (SDT) are shown in the le� part of Table 1. �edictator – Player X – had to decide between an unequal allocation (Option A) and an equalallocation (Option B). When the dictator chose Option A (Option B) then he/she received apayo� of 6 ECU (5 ECU) and the recipient received a payo� of 1 ECU (5 ECU).

Single Dictator Treatment: Multiple Dictator and Computer Dictator Treatments:

Player X’s choices A Y:1X:6

B Y:5X:5

Player Y’s choicesA B

Player X’s choices A Y:6X:6 Z:1

Y:5X:5 Z:5

B Y:5X:5 Z:5

Y:5X:5 Z:5

Table 1: Binary Dictator Game

3.2.2. Multiple Dictator

Payo�s for the Multiple Dictator Treatment (MDT) are shown in the right part of Table 1.Dictators – Player X and Player Y – both made a choice that determined the payo� for bothdictators and the recipient. �e unequal payo� was only implemented if both dictators choseOption A. In all other cases, Option B was implemented. For example, if both dictators choseOption A then both dictators received a payo� of 6 ECUs while the recipient received a payo�of 1 ECU, however, if at least one of the two dictators chose Option B then the dictators aswell as the recipient received a payo� of 5 ECU.

3.2.3. Computer Dictator

�e Computer Dictator Treatment (CDT) was identical to the MDT with one exception: Oneout ot the two dictators – Player Y – acted as a so called “passive dictator”. While still obtainedpayo�s for Player Y as given in Table 1, the dictator had no in�uence on the choice as thechoice was made by a computer. �e frequency with which the computer chose options Aor B followed the choices of dictators in an earlier Multiple Dictator Treatment. �is was alsotold to the participants in the CDT. Hence, all Player X in the CDT had the same beliefs (andthe same ambiguity) about the other players behavior as in the MDT. Furthermore, sincepayo� rules for Player Y in CDT were the same as in MDT, social concerns did not di�erbetween CDT and MDT.

3.3. Measurement of Perceived Responsibility and GuiltA�er the dictators made their choice but before participants were informed about the �naloutcome and payo�, dictators were asked to describe their perceived personal responsibilityfor the outcome as well as their feeling of guilt if the unequal payo� allocation would be

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implemented with the help of a questionnaire.3 In addition, dictator(s) were also asked tostate their perceived responsibility for the payo� of the co-dictator(s) and for the payo� ofthe recipient. We used these questions as a proxy for the perceived responsibility and guiltfor the �nal outcome and the perceived respondibility for the other participants. Similarto Luhan et al. (2009) dictators also had the possibility to explain in an open question whythey had chosen a speci�c option. Furthermore, in MDT and CDT, dictators were asked tostate what they expected the other human co-dictator or the computer to choose and howresponsible and guilty they would perceive the human co-dictator or the computer to be ifthe unequal payo� allocation would be implemented.

We also asked the recipients and, depending on the treatment, also the passive dictatorsabout their expectation what the dictator(s) or the computer will choose. In addition, theywere asked how they assess the responsibility and guilt felt by the dictators if the game wouldresult in an unequal payo� allocation and had the possibility to state why they expected thedictator(s) to choose a speci�c option. Recipients as well as passive dictators were asked tocollect additional data on how the deicision situation is perceived by a possibly loosing orwinning party with no right of decision and to maintain the anonymity of the recipients andpassive dictators in the lab.

We also conducted a manipulation check by asking how participants would evaluate thesituation used in the other treatment and collected some demographic data. Data and meth-ods are available online.4

4. Theoretical Framework and Behavioral HypothesesA purely sel�sh participant would take into account neither the welfare of others nor situa-tional circumstances. In particular, for such a participant it would not ma�er if the decisionis taken alone, with another person or with a computer. Similarly, a participant with �xedsocial preferences should follow these preferences, independent of the type of the interactionpartner, human or computer. However, from other studies we know that social preferencesdepend on the salience of the link between actions and consequences. Chen and Schonger(2013) as well as Haisley and Weber (2010) show that certainty or ambiguity of the outcomema�ers. Grossman and van der Weele (2013), Grossman (2014) and Ma�hey and Regner(2011) argue that the availability of excuses that allow to justify a sel�sh behaviour a�ectsocial preferences. �ese �ndings can be justi�ed with the help of models of social imageconcerns (see Andreoni and Bernheim, 2009; Benabou and Tirole, 2006; Ellingsen and Johan-nesson, 2008; Grossman, 2015) and models on self-perception maintenance (see Aronson,2009; Beauvois and Joule, 1996; Bodner and Prelec, 2003; Konow, 2000; Mazar et al., 2008;Murnighan et al., 2001; Rabin, 1995). According to these models, individuals do not onlymaximize their own output but also want to be perceived by others as kind and fair. Indi-viduals also want to see themselves in a positive light. However, if these two goals are atodds, choosing an option that maximizes own output causes an unpleasant tension for theindividual that can only be reduced by lowering the perceived con�ict of interest between

3For the exact wording of the questionnaire see Section A.1.2.4https://www.kirchkamp.de/research/shareMachine.html

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the two goals.5 �ereby, as research in social psychology has shown, people seem to actselectively and in a self-serving way when determining whether a self-interested behaviorwill have a positive or negative impact on their own self-concept or social image and usesituational excuses, if available, to justify their decision (see Rabin, 1995; Haidt and Kesebir,2010). �is allows individuals to a�ribute sel�sh actions to the context, instead of having toa�ribute it to the own self-concept and thus makes it easier to choose a sel�sh option as itenables to uphold a comfortable self- and social image.

As a result, the perceived personal responsibility of a dictator decreases when other de-ciders are involved in the decision. If the decision is shared, the dictator might only feelresponsible for a fraction of the harm caused by a self-interested decision. Furthermore, asstated by Berndsen and Manstead (2007) and Bruun and Teroni (2011), the less responsible anindividual feels, the less guilt they feel for making a sel�sh decision. In addition, the di�usedpivotality due to the uncertainty of the impact of the decision also provides an excuse to feelless responsible for the �nal outcome (see Bartling et al., 2015; Falk and Szech, 2013). �us,sharing a decision with another human makes it easier to choose a self-serving option as itallows to reduce the perceived negative consequences for the self- and social image.

Since in our experiment Option B leads to an equal payo� for all participants choosing Bcauses less harm to the social and self-image than choosing Option A, where the recipientreceives much less than the dictator(s). Dictators who value a positive perception by othersand themselves clearly higher than their own monetary output will have a clear preferencefor B. Dictators who value mainly the monetary output will prefer A. However, a dictatorwho strives to maximize own pro�ts but who, at the same time, also tries to maintain apositive self- and social image faces two con�icting desires: maximize their own output bychoosing Option A or maintain a positive self- and social image by choosing Option B.

In the SDT the �nal payo�s only depends on the choice of the dictator and thus o�ers nosituational excuse to reduce the negative impact on the self- and social image caused by asel�sh decision. Sharing a decision with another dictator allows room for the interpretationof a sel�sh behavior as bene�cial for the majority, and enables the a�ribution of a sel�shdecision to the situation or circumstance rather than to the dictator.6 We expect that dictatorsin the MDT perceive themselves to be less responsible for the �nal outcome (Hypothesis 1.i)as well as to feel less guilty for a sel�sh decision (Hypothesis 2.i) than dictators in the SDT.As a result we expect more sel�sh decisions in the MDT than in the SDT (Hypothesis 3.i).

Turning to the CDT we must ask whether computer dictators are as responsible as humandictators. Can computers be in the same way responsible for an action? In the literaturewe �nd in particular the following three conditions required to be held responsible: First, anagent needs to have action power, meaning there has to be a causal relationship between ownactions and the outcome (see Lipinski et al., 2002; May, 1992; Moore, 1999; Nissenbaum, 1994;Scheines, 2002). Second, the agent must be able to choose freely, including the competenceto act on the basis of own authentic thoughts and motivations as well as the capability tocontrol one’s own behavior (see Fischer, 1999; Johnson, 2006). �ird, to be held responsible

5�e unpleasant tension (or in a more formal speech “disutility”) is o�en described as nothing else than thefeeling of guilt (see Berndsen and Manstead, 2007; de Hooge et al., 2011; Stice, 1992).

6However, as either dictator can independently implemented the equal outcome by choosing Option B theaddition of a second dictator does not impede subjects from ensuring a fair outcome if they prefer it.

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requires the ability to consider the possible consequences an action might cause (see Bechel,1985; Friedman and Kahn, 1992). Some researchers even argue that it is necessary to becapable to su�ering or gaining from possible blame or praise and thus being culpable forwrongdoing (see Moor et al., 1985; Sherman, 1999; Wallace, 1994). �ese conditions wouldalso have to be satis�ed by a computer in order for it to be held responsible. As the causalresponsibility of a computer for an outcome cannot be denied, it neither has a free will northe freedom of action (see Floridi and Sanders, 2004; Johnson and Powers, 2005; Sparrow,2007) and is also not able to consider possible consequences of its actions in the same wayas a human (see Bechel, 1985; Friedman and Kahn, 1992; Moon and Nass, 1998). A computeris also not capable of any kind of emotions (see Asaro, 2011; Snapper, 1985; Sparrow, 2007).�is illustrates that a computer does not ful�ll the conditions under which it would makesense to hold it responsible to the same extent as a human. Research in machine and roboterethics even a�ributes only operational responsibility to the most advanced machines todaybut denies any higher form of (moral) responsibility as today’s machines are still having arelatively low level of own autonomy and ethical sensitivity (see Allen et al., 2000; DeBaets,2014; Denne�, 1997; Moor et al., 1985; Sullins, 2006).

Based on this the responsibility for a sel�sh outcome can not be shared with a computerto the same extent as with a human and the wiggle room is smaller than in a shared decisionwith another human. �us, upholding a positive self- and social image while deciding self-ishly together with a computer should not be as easy as when deciding with another human.For this reasons we expect dictators to perceive a higher level of personal responsibility forthe �nal outcome (Hypothesis 1.ii) and guilt when choosing the unfair option (Hypothesis2.ii) in the CDT than in the MDT. In addition, as sel�sh decision-making is in�uenced bythe individual’s perception of being responsible or feeling guilty for a decision, signi�cantlymore people should choose the sel�sh option if they are deciding with another human (MDT)compared to with a computer (CDT) (Hypothesis 3.ii).

Hypothesis 1 In a situation where the outcome depends on the decision of two humans (Multi-ple Dictator Treatment), participants a�ribute less responsibility to the dictator for the outcomeresulting from choosing the sel�sh option than

(i) if the outcome is determined by a single dictator (Single Dictator Treatment) or, alterna-tively,

(ii) if the outcome depends on the decision of a human and a computer (Computer DictatorTreatment).

Hypothesis 2 In a situation where the outcome depends on the decision of two humans (Multi-ple Dictator Treatment), participants a�ribute less guilt to the dictator for the outcome resultingfrom choosing the sel�sh option than



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Hypothesis 3 In a situation where the outcome depends on the decision of two humans (Mul-tiple Dictator Treatment), the sel�sh option is chosen more o�en than



5. ResultsAll sessions were run in July, October and November 2016 at the Friedrich Schiller UniversitatJena. �ree treatments were conducted with a total of 399 subjects (65.2% female).7 Most ofour subjects were students with an average age of 25 years. Participants earned on average€9.43. �e data for all statistical tests is independent for the di�erent treatments as we applieda between-subject design.

We �rst analyze how the perceived responsibility for the �nal outcome as well as thefeeling of guilt for a self-serving decision varied between the treatments before presentingthe �ndings regarding the choices made by the dictators.

5.1. ResponsibilityWe considered di�erent kinds of responsibilities to check whether the perceived responsibil-ity for a sel�sh decision varies between the treatments. Hence, dictators were asked to statethe level of responsibility for the �nal outcome that they perceive, the level of responsibilitythey perceive for the payo� the recipient and, if existing, the the level of responsibility thatthey perceive for their co-dictators’ payo�.8

We also asked the recipients and, if existing, the passive dictators to state the level ofresponsibility they a�ribute to the dictator(s) for the �nal outcome as well as for their ownpayo� and, if existing, the payo� of the other human in the game.9

For all questions the level of responsibility was measured by a continuous scale from “Notresponsible at all” (0) to “Very responsible” (100).

5.1.1. Responsibility of the human dictator(s)

Figure 1 shows the perceived personal responsibility for the �nal outcome by the dictator(s).10

In Figure 2, the responsibility a�ributed by the recipients to the human dictator(s) is shown.11

7In total 124 subjects (62.9% female) participated in the SDT, 92 subjects (68.5% female) in the MDT and 183subjects (65% female) in the CDT. We have, thus, almost the same number of actively deciding dictators ineach treatment (see Table 5).

8For the exact wording see �estion 9 from Section A.1.2.9For the exact wording see �estion 6 and �estion 7 from Section A.1.2.

10�e Figure is split up, sharing the results for dictators who have chosen Option A on the le� and dictatorswho have chosen Option B on the right.

11Passive dictator responses are analyzed in the Appendix Section A.6.3.

10

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B

computer multiple single

Figure 1: Perceived personal responsibility by dictators(�estion 9 from Section A.1.2)

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100


Figure 2: Personal responsibility assigned to the human dictator by recipients(�estion 9 from Section A.1.2)

multiple/single multiple/computerdictator [-Inf,-11.37] (0.0000) [-Inf,5.914] (0.3495)

recipient [-Inf,1.855] (0.1042) [-Inf,0.6293] (0.0662)

Table 2: Treatment di�erence in the personal responsibility of the human dictator(s) by dic-tators and recipients

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Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B

computer multiple

Figure 3: Responsibility assigned to the computer or human co-dictator by dictators(�estion 9 from Section A.1.2)

As Table 212 shows we can clearly con�rm Hypothesis 1.i for the dictators, i.e. that the re-sponsibility for the outcome perceived by the dictator is lower if the decision is shared withanother human compared to when the dictator has to decide alone. However, the respon-sibility assigned to the dictator(s) by the recipients did not di�er signi�cantly between theSDT and the MDT. �us, we can not con�rm Hypothesis 1.i for the recipients.

�e same �gures and tables can be used to analyse Hypothesis 1.ii. While the preceivedresponsibility for the �nal decision did not di�er signi�cantly for dictators, the recipientsperceived the human dictator in the MDT as slightly more responsible for the decision thanthe computer dictator in the CDT. �us, Hypothesis 1.ii, i.e. that the personal responsibilityfor the outcome perceived by the dictator is lower if the decision is shared with anotherhuman than with a computer, can not be con�rmed for dictators but weakly be con�rmed forrecipients. Interestingly, it even seems as recipients expected a lower level of responsibilityperceived by the dictators in the CDT than in the SDT.

5.1.2. Responsibility of the co-Dictator

�e co-dictator was either a human (in the MDT) or a computer (in the CDT). Figure 3 as wellas Figure 4 show a signi�cant di�erence in responsibility assigned to the other dictator bydictators as well as by recipients between the MDT and the CDT. As Table 3 shows, dictatorsas well as recipients perceived the human dictator in the MDT on average as signi�cantlymore responsible for the �nal outcome than the computer in the CDT . However, for dictatorsthis e�ect was mainly driven by dictators who chose Option B.

When comparing the responsibility the dictators assign to themselves with the respon-

12�e following p-values are based on t-tests, unless stated otherwise.

12

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer multiple

Figure 4: Responsibility assigned to the computer or human co-dictator by recipients(�estion 9 from Section A.1.2)

Di�erence in responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-100 -50 0 50 100

A

-100 -50 0 50 100

B

computer multiple

Figure 5: Di�erence between the personal responsibility reported by the dictator and theresponsibility assigned to the computer or human co-dictator by dictators

(�estion 9 from Section A.1.2)

13


Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-50 0 50 100

computer multiple

Figure 6: Di�erence between the personal responsibility assigned to the dictator and the re-sponsibility assigned to the computer or human co-dictator by recipients


multiple/computerdictator [-Inf,-4.935] (0.0042)

recipient [-Inf,-13.06] (0.0000)

Table 3: Treatment di�erence between the personal responsibility of the human dictator andthe computer or human co-dictators’ responsibility by dictators and recipients

14

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B

computer multiple

Figure 7: Perceived personal responsibility for the active or passive co-dictator by dictators(�estion 7 from Section A.1.2)

multiple/computer pass. multiple/single resp. multiple/computer resp.dictator [8.547,Inf] (0.0014) [-Inf,2.473] (0.1269) [-Inf,5.747] (0.2814)

recipient [-Inf,6.779] (0.3505) [-2.956,Inf] (0.2614) [-Inf,-8.782] (0.0000)

Table 4: Treatment di�erence between the personal responsibility for the recipient and thepassive dictator by dictators and recipients

sibility the dictators a�ribute to their co-dictator (see Figure 5) it becomes clear that thedi�erence is more dispersed in the CDT, where dictators decided together with a computer,than in the MDT, where dictators decided together with another human dictator. Means,however, are similar (p-value 0.0637).

�e same holds true for recipients as Figure 6 shows. However, the di�erence betweenthe responsibility assigned to the dictator and to the computer in the CDT is clearly andsigni�cantly more dispersed than the di�erence between the responsibility assigned to thedictators in the MDT (p-value 0.0017).

5.1.3. Responsibility for the active or passive human co-Dictator and the Recipient

Dictators in the MDT (CDT) were asked to state how responsible they feel for the �nal payo�of the active (passive) human co-dictator, and also for the payo� of the recipient. �e personalresponsibility perceived by the dictators for the, if present, active or passive co-dictator andthe recipient are shown in Figures 7 and Figure 8. As shown in Table 4 dictators stated toperceive a signi�cantly higher level of responsibility for the payo� of the passive dictator inthe CDT than for the actively deciding dictator in the MDT. However, their perceived level of

15

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B


Figure 8: Perceived personal responsibility for the recipient by dictators(�estion 6 from Section A.1.2)

responsibility for the recipients’ payo� did not di�er signi�cantly between the treatments. Itis also important to note that the overall level of responsibility perceived by dictators for therecipients’ payo� was higher for dictators who chose Option B compared to dictators whochose Option A, in all treatments. In addition, we also asked the recipients to evaluate thelevel of responsibility they expect the dictator(s) to perceive for the payo� of the recipientand, if present, the active or passive co-passive dictator’s payo�.13

Interestingly, recipients did not expect dictators to perceive a higher level of responsibil-ity for the active dictators’ payo� than for the payo� of the passive dictator, whereas theyexpected the dictators to perceive themselves to be signi�cantly more responsible for therecipients’ payo� in the CDT than in the MDT.14

5.1.4. Responsibility Findings

�e �ndings regarding the responsibility can be summed up in three points.(a) Dictators perceived themselves to be, on average, signi�cantly less responsible for their

decision in the MDT than in the SDT but the perceived level of personal responsibility forthe decision did not di�er signi�cantly between the CDT and the MDT. Recipients, however,expected that dictators would perceive themselves to be more responsible in the CDT thanin the MDT (weak signi�cant) but did not expect dictators in the SDT to perceive themselvesto be more responsible than in the MDT.

Furthermore, (b) dictators as well as recipients assigned less responsibility to a computerin the CDT than to a human co-dictator in the MDT.

13For the exact wording of the question see �estion 6 from Section A.1.2.14For the corresponding �gures of the recipients evaluation see Figure 24 and Figure 25 in Section A.4.3.

16

Guilt

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B


Figure 9: Perceived guilt by dictators(�estion 8 from Section A.1.2)

And �nally, (c) dictators felt signi�cantly more responsible for the payo� of the passivedictator in the CDT than for the other actively deciding dictator in the MDT which was notanticipated by the recipients, as the recipients did not expect a signi�cant di�erence in thedictators perception of responsibility towards an active or a passive dictator.

�us, Hypothesis 1.i, i.e. that the perceived personal responsibility for the outcome by thedictator is lower if the decision is shared with another human can be con�rmed for dictatorsbut not for recipients.

Hypothesis 1.ii, i.e. that the perceived personal responsibility for the outcome by the dic-tatoris lower if the decision is shared with another human than with a computer can notbe con�rmed for dictators but weakly be con�rmed for recipients. In addition, as might beexpected dictators as well as recipients perceived a computer to be less responsible than ahuman dictator.

5.2. GuiltIn all treatments dictators were asked to state their perceived guilt in case option A wouldbe implemented.15 In addition, recipients were asked to state how guilty they expect thedictator(s) to feel for a possible unequal �nal payo�.16 �e level of guilt was measured by acontinuous scale from “not guilty” (0) to “totally guilty” (100).

According to Hypothesis 2.i, we expect the perceived guilt for an unequal outcome to belower in the MDT than in the SDT. Furthermore, as stated in Hypothesis 2.ii, we expect alower level of perceived guilt if the outcome depends on the decision of two human dicta-

15For the exact wording of the question see �estion 8 from Section A.1.2.16Passive dictator responses are analyzed in the Appendix Section A.6.5.

17

Guilt

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100


Figure 10: Personal guilt assigned to the dictator(s) by recipients(�estion 8 from Section A.1.2)

Treatment Proportion choosing Acomputer dictator treatment 28/61 (45.9%)multiple dictator treatment 33/61 (54.1%)single dictator treatment 24/62 (38.7%)

Table 5: Number of sel�sh choices by treatments(for the �estion see Figure 11 in Section A.1)

tors, as in the MDT, than if the outcome depends on the decision of a human dictator and acomputer, as in the CDT.

�e dictators’ perceived level of guilt, if Option A would be implemented, is shown inFigure 9. Apparently, Hypothesis 2.i, that dictators feel less guilty in the MDT than in theSDT can not be con�rmed (p-value 0.1875). �e same also applies for Hypothesis 2.ii asdictator did not feel less guilty when deciding with another human than when deciding witha computer (p-value 0.4344).

Figure 10 also shows that the recipients did not expect the dictator(s) to feel more guiltyfor an unequal �nal outcome in the CDT than in the MDT (p-value 0.7664). �us, neitherHypothesis 2.i nor Hypothesis 2.ii can be con�rmed for dictators and recipients.

In sum, dictators did not feel signi�cantly more or less guilty for a sel�sh decision if theyhad to decide on their own, together with a computer or another human. Recipients alsoexpected no signi�cant di�erence in the dictators’ perceived level of guilt for a unequal out-come between the treatments.

18

exp. no. of A choices computer multiple single0 37.7 6.5 64.51 62.3 29.0 35.52 0.0 64.5 0.0

Table 6: Recipients’ expectations of “A” choices [%](for the �estion see Figure 12 in Section A.1)Note that in the single and computer treatments there is only a single opponent, hence, there can be no morethan one A choice.

5.3. Choices and Expected ChoicesAn overview of the sel�sh-choices per treatment can be found in Table 5.17 �e number ofsel�sh choices made by the dictators varied among the di�erent treatments. However, we�nd only weak support for Hypothesis 3.i, i.e. that when the outcome depends on the decisionof two human dictators, the sel�sh option is chosen more o�en than when the outcome isdetermined by a single dictator (p-value18 0.0630). Regarding Hypothesis 3.ii, i.e. that whenthe outcome depends on the decision of two human dictators the sel�sh option is chosenmore o�en than if the outcome depends on the decision of a human dictator and a computer,we see that the proportion of sel�sh choices in CDT is somewhere between SDT and MDT.�is is in line with our hypothesis. �e e�ect is, however, small and not signi�cant (p-valuefor more sel�shness in MDT than in CDT is 0.2344, for more sel�shness in CDT than in SDTis 0.2661).

Table 6 summarises the recipients’ expectations for the number of Option A-choices in thethree treatments. Indeed, recipients expected signi�cantly more sel�sh choices (per dictator)in MDT (p-value19 0.0001) and CDT (p-value 0.0017) than in SDT. Furthermore, recipients alsoexpected fewer sel�sh choices (per dictator) in CDT than in MDT (p-value 0.0544).

6. Conclusion�e number of decisions made by human-computer teams have already increased substan-tially in the past and will continue to increase in the future. Here we study whether humansperceive a decision shared with a computer di�erently than they perceive a decision sharedwith another human. More speci�cally, we focus on the perceived personal responsibilityand guilt for a sel�sh decision when a decision is shared with a computer instead of with an-other human. Other studies have established that humans behave more sel�shly if they shareresponsibility with other humans. We can replicate this �nding in our experiment, even forhuman-computer interactions. We �nd that, if responsibility is shared with a machine, moresel�sh choices are made than if decisions are taken alone, but fewer than if decisions aremade together with a human. However, di�erences in actual choices are not signi�cant. We

17For the binary Dictator Game interface shown to the dictators and to the recipients see Section A.1.1.18�e p values in this paragraph are based on tests for proportionality.19�e p-values in this paragraph are based on a logistic model.

19

do, however, get signi�cant e�ects in expectations: Essentially, sharing responsibility with amachine does not permit as much sel�sh behaviour as sharing it with a human, but de�nitelymuch more than when deciding alone.

We investigate two potential reasons why humans may expect fewer sel�sh decisions if thedecision is shared with a machine: responsibility and guilt. �e personal level of responsibil-ity is clearly perceived as lower once a second decision maker comes into play. Interestingly,it does not ma�er whether the second decision maker is a machine or a human. Althoughour participants a�ribute more responsibility to a human counterpart, their personal respon-sibility is reduced both with a computer and a human partner by very similar amounts. Guiltdoes not seem to be a�ected by the type of the interaction.

Our results underline the importance of an open discussion of hybrid-decision situations.In future, it might not only be important to address the technical question of what we canachieve by using computers but also how humans perceive computer actions and how hisin�uences their own decision-making.

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A. Appendix for Online PublicationIn addition to the data used to test your hypotheses we collected some further data thatwe provide here. We also present some additional information on the interfaces and ques-tions used. Data and Methods can be found at https://www.kirchkamp.de/research/shareMachine.html.

A.1. Interfaces and�estionsIn this section the interfaces as well as the questions used in the experiment are presented.

A.1.1. Dictator Game Interface

In the MDT as well as in the CDT dictators used the interface sketched in Figure 11 to entertheir decision. Recipients used the interface sketched in Figure 12 to enter their guess.

Please make a decision:Option A

(will be implemented if player X and player Y choose A)

Player X receives 6 ECUPlayer Y receives 6 ECUPlayer Z receives 1 ECU

Option A

Option B(will be implemented if player X and player Y choose B)


Option B

Figure 11: Dictator Game interface for dictators

Players X and Y are confronted with the following decision-making situation:Option A

(will be implemented if player X and player Y choose A)


Option B(will be implemented if player X and player Y choose B)


What do you think: how many players in your group will choose option A?Your assessment does not a�ect the outcome of the game.

Your assessment:0 players1 player2 players

OK

Figure 12: Dictator Game interface for recipients

�e interfaces for dictators and recipients in the SDT were similar to the interfaces used inthe MDT and in the CDT with the exception that there were just two players, of which onewas a dictator who would gain an advantage if Option A becomes implemented. Accordingly,recipient in the SDT were just asked regarding their guess for Player X’s choice.

27



A.1.2. �estions

To determine the levels of responsibility and guilt that the dictators perceived all subjectswere asked to answer some questions. �e questions were asked right a�er the decisionand before the �nal outcome and payo� was announced. �ey di�ered slightly between thetreatments as they were adjusted to the di�erent situations. �e questions used in the MDTfor the subject in the roll of Player X are presented below as an example. �e used answermethod is presented in brackets. �e same questions were asked in the CDT, however “PlayerY” was replaced by “the computer”. �e questions were also asked in the SDT, except for the�rst three question. �e questions for Player Y in the MDT were very similar to the questionsasked to Player X. In the SDT the questions were altered as Player Y did not decide on herown. In the SDT the questions for Player Y were similar to the questions asked to Player Zin the CDT and MDT as all of them were recipients. Recipients were asked what they expectPlayer X to do.

While dictators were asked directly recipients and passive dictators were asked indirectly.For example, recipients and passive dictators, were asked how responsible and guilty theyperceive the dictator(s) and what they expect the dictator(s) would do in a speci�c situation.We also asked the recipients and passive dictators to estimate how responsible and guilty thedictators perceive themselves for a decision in the experiment as well as in the manipulationcheck.

1. How would you have decided, if you would have made the decision on your own?[Slider from “Option A” to “Option B”] (for an analysis of the answers given see SectionsA.2.1, A.4.1, A.6.1)

2. What likelihood did you assume for Player Y to choose Option A (Player X receives 6ECU, Player Y receives 6 ECU, Player Z receives 1 ECU)? [Slider from “Player Y alwayschooses A” to “Player Y always chooses B”] (for an analysis of the answers given seeSections A.2.2, A.4.2, A.6.2)

3. Did the likelihood you assumed for Player Y to choose Option A (Player X receives 6ECU, Player Y receives 6 ECU, Player Z receives 1 ECU) a�ect your decision? [Radiobu�ons “YES”; “NO”] (for an analysis of the answers given see Sections A.2.3)

4. Why did you choose Option A (Player X receives 6 ECU, Player Y receives 6 ECU,Player Z receives 1 ECU)? [Open question with a maximum of 100 characters] / Whydid you choose Option B (Player X receives 5 ECU, Player Y receives 5 ECU, Player Zreceives 5 ECU)? [Open question with a maximum of 100 characters] (for the answersgiven see online dataset)

5. What could be additional reasons for choosing option A(player X receives 6 ECU,player Y receives 6 ECU, player Z receives 1 ECU)? [Open question with a maximumof 100 characters] (for the answers given see online dataset)

6. I feel responsible for the payo� of Player Z. [Slider from “Very responsible” to “Notresponsible at all”] (for an analysis of the answers given see Sections 5.1, A.4.3, A.6.3)

28

7. I feel responsible for the payo� of Player Y. [Slider from “Very responsible” to “Notresponsible at all”] (for an analysis of the answers given see Sections 5.1, A.4.3, A.6.3)

8. Option A will be implemented if you and the other player chose A. In this case, PlayerX receives 6 ECU, Player Y receives 6 ECU and Player Z receives 1 ECU. Do you feelgulity in this case? [Slider from “I feel very guilty” to “I do not feel guilty at all”] (foran analysis of the answers given see Sections 5.2, A.6.5)

9. Option A will be implemented if you and the other player chose A. In this case, PlayerX receives 6 ECU, Player Y receives 6 ECU and Player Z receives 1 ECU. Please adjustthe slide control, so that it shows how you perceive your responsibility as well asthe responsiility of the other player if option A is implemented. [Slider from “I amfully responsible” to “I am not responsible” and slider from “My fellow player is fullyresponsible” to “My fellow player is not responsible”] (for an analysis of the answersgiven see Sections 5.1, A.4.3, A.6.3)

In addition to these questions, a manipulation check was conducted in all treatments. Sub-jects participating in the MDT were asked in the manipulation check how responsible andguilty they would feel for the �nal payo� if the decision of one of the dictators would bemade by a computer instead of a human.20 Subjects participating in the CDT were asked inthe manipulation check how responsible and guilty they would feel for the �nal decision ina situation similar to the MDT (two humans decide together which option should be imple-mented instead of a computer).21 In the SDT subjects were asked in the manipulation checkhow responsible and guilty they would feel for the �nal decision if a computer instead ofthemselves would decide which option will be implemented.22 As an example, the questionsfor Player X used in the MDT manipulation check are presented below.

1. How responsible would you feel in this situation for the payo� of Player Y? [Radiobu�ons “As responsible as in the experiment” ; “More responsible than in the experiment” ;“Less responsible than in the experiment”] (for an analysis of the answers given seeSections A.3.2, A.5.2, A.7.2)

20�e wording of the manipulation check in the MDT was “Imagine, now the decision of player X [Y] is made bya computer. �e likelihood the computer chooses Option A (Player X receives 6 ECU, Player Y receives 6 ECU andPlayer Z receives 1 ECU) or Option B (Player X receives 5 ECU, Player Y receives 5 ECU and Player Z receives1 ECU) is as high as the likelihood experimental subjects chose Option A or Option B in a former experiment.Example: If three out of ten participants in a former experiment, whose decision a�ected the payment, chosea particular option the computer would choose that option with a probability of 30%. �e participants in theformer experiment were not told that their decision would a�ect a computer’s decision in this experiment.Please compare this decision-making situation with the one Player X and Player Y are confronted with in thisexperiment.”.

21�e corresponding wording of the manipulation check in the CDT was “Imagine, now the decision would notbe made by a computer but by player Y[X] him/herself. Please compare this decision situation to the situationyou were confronted with in this experiment.”.

22�e adjusted �rst sentence of the manipulation check in SDT was “Imagine, now the decision of player X ismade by a computer.”

29

2. How responsible would you feel in this situation for the payo� of Player Z? [Radiobu�ons “As responsible as in the experiment” ; “More responsible than in the experiment” ;“Less responsible than in the experiment”] (for an analysis of the answers given seeSections A.3.3, A.5.3, A.7.3)

3. How guilty would you feel if you and the computer both chose Option A and thereforeOption A (Player X receives 6 ECU, Player Y receives 6 ECU, Player Z receives 1 ECU)would be implemented? [Radio bu�ons “As guilty as in the experiment” ; “More guiltythan in the experiment” ; “Less guilty than in the experiment”] (for an analysis of theanswers given see Sections A.3.4, A.5.4, A.7.4)

4. Option A will be implemented if you and the computer chose Option A. In this case,Player X receives 6 ECU, Player Y receives 6 ECU and Player Z receives 1 ECU. Pleaseadjust the slide control, so that it shows your preceived responsibility as well as theresponsibility you assign to the computer if option A is implemented.[Slider from “I amresponsible” to “I am not responsible” and slider from “�e computer is fully responsible”to “�e computer is not responsible”] (for an analysis of the answers given see SectionsA.3.1, A.5.1, A.7.1)

A.2. Dictator: Further MeasurementsIn addition to question regarding the perceived responsibility and guilt for the outcome weasked the dictators further questions about their expectations. Even if these questions arenot necessary to our research question the results may be interesting for others.

A.2.1. Deciding Alone

Subjects were able to insert their assessment by a continuous scale from “Option A” (0) to“Option B” (100). A large proportion of the actively deciding dictators in the CDT and in theMDT who had chosen Option A stated that they would have chosen Option A if they wouldhave had to decide on their own as Figure 13 shows. �is was stronger for dictators in theCDT than for dictators in the MDT (p-value 0.0000). In accordance, dictators in the MDT aswell as in the CDT who had chosen Option B stated a higher probability of choosing OptionB if they would have had to decide alone.

A.2.2. Expectation Regarding the Behavior of the Other Human Dictator orComputer

�e expectation was measured by a continuous scale from “Player [Computer] choose alwaysA” (0) to “Player [Computer] choose always B” (100). Dictators expected the other human orcomputer dictator to make a choice similar to their own as Figure 14. Interestingly, dictatorsin the MDT expected the other human dictator to choose Option A signi�cantly more o�enthan dictators in the CDT expected the computer to choose Option A (p-value 0.0011). �isresult was mainly driven by dictators in the MDT who had chosen Option A (p-value 0.0001).

30

Propensity to choose Option B

Empi

rical

CDF

0.0

0.2

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1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B

computer multiple

Figure 13: Deciding alone (as a hypothetical single dictator) by actively deciding dictators(�estion 1 from Section A.1.2)

Expected probability of choosing Option B

Empi

rical

CDF

0.0

0.2

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0.6

0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B

computer multiple

Figure 14: Expected other dictators’ choice as seen by actively deciding dictators(�estion 2 from Section A.1.2)

31

Responsibility

Empi

rical

CDF

0.0

0.2

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0.8

1.0

0 20 40 60 80 100

A

0 20 40 60 80 100

B


Figure 15: Perceived personal responsibility in the manipulation check by dictators(�estion 4 from Section A.1.2)

A.2.3. Influence on Own Decision

Dictators could either choose “YES” or “NO”. In both treatments, the MDT and the CDT, thefraction of dictators who stated that they took the expected decision of the other decider intoaccount when making their own decision was very similar (34.4% in the MDT and by 36.1%in the CDT).

A.3. Dictator: Manipulation CheckDictators participating in the MDT [CDT] were asked to state the responsibility and guiltthey would perceive for the outcome as well as the level of responsibility they would assignto the other dictator if, contrary to the game they just played, they would have to decidetogether with a computer [another human dictator]. Dictators participating in the SDT wereasked to state how responsible they would feel for the outcome if a computer would decideinstead of themselves.23

A.3.1. Manipulation Check: Perceived Own and Others Responsibility

�e perceived responsibility was measured by a continuous scale from “Not responsible atall” (0) to “Very responsible” (100). �e personal responsibility perceived by the dictators inthe manipulation check is shown in Figure 15. Dictators in the SDT stated to perceive them-selves to be not very responsible if the decision would be made by a computer. Interestingly,dictators in the CDT stated to perceive themselves to be less responsible for the �nal payo�

23A detailed description of the manipultation check can be found in Section A.1.2.

32

Change in responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-100 -50 0 50

A

-100 -50 0 50

B


Figure 16: Change in personal responsibility in the manipulation check by dictators�e �gure shows the di�erence between the personal responsibility in the hypothetical situation described inSection A.3 and the personal responsibility in the actual experiment as perceived by the dictators (as shown inFigure 1).

if they would have to decide with another human dictator, than dictators in the MDT, whowould have to decide with a computer instead of another human dictator (p-value 0.0011).

For a comparison of the relative change between the perceived personal responsibility inthe hypothetical situation and the perceived personal responsibility in the actual experimentsee Figure 16. In line with Hypothesis 1.i , dictators in the SDT stated that they would feelless responsible if a computer would decide on their behalf (p-value 0.0000). In line withHypothesis 1.ii, the perceived personal responsibility also increased for dictators in the MDTwhen their counterpart would be replaced by a computer (p-value 0.0130). Interestingly, theperceived personal responsibility did not decrease signi�cantly for dictators in the CDT whentheir counterpart would be replaced by a human (p-value 0.5806).

�e responsibility assigned to the other dictator by the dictators in the manipulation checkis shown in Figure 17. Signi�cantly more responsibility was assigned to a potential humandictator in the CDT maipulation check compared to a potential computer dictator in the MDT(p-value 0.0001).

�e increase or decrease in the responsibility assigned to the other dictator between thehypothetical situation and the actual experiment is shown in Figure 18. In line with Hypoth-esis 1.ii, responsibility a�ributed to the other player in the CDT increases signi�cantly oncethe other player is no longer a computer (p-value 0.0196). Similarly, responsibility decreasessigni�cantly in the MDT once the other player is no longer a human (p-value 0.0000).

33

Rresponsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100


Figure 17: Personal responsibility assigned to a human or computer co-dictator in the ma-nipulation check by dictators


Di�erence in personal responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-100 -50 0 50 100

A

-100 -50 0 50 100

B

computer multiple

Figure 18: Di�erence between the responsibility assigned to a human or computer co-dictatorin the manipulation check by dictators

�e Figure shows the di�erence in the personal responsibility assigned by the dictator to the human or computerco-dictator between the hypothetical situation (described in Section A.3) and the actual experiment (as shownin Figure 3).

34

Treatment

Resp

onsib

ility

computer multiple

less

sam

em

ore

A B A B

Figure 19: Change in personal responsibility for the active or passive co-dictator in the ma-nipulation check by dictators


A.3.2. Manipulation Check: Responsibility for the Other Dictator

�e perceived responsibility was measured by using three statements: “Same level of respon-sibility as in the experiment before”, “More responsible as in the experiment before” and “Lessresponsible as in the experiment before”. Results are shown in Figure 19. Hypothesis 1.ii sug-gests that dictators in the CDT who would share their decision with a human instead of acomputer would feel less responsible for the payo� of the other dictator than before. �is iscon�rmed by a binomial test (p-value from a binomial test 0.0000). Similarly we expect thatdictators in the MDT who would share their decision with a computer feel more responsiblefor the payo� of the other dictator. However, this was not the case (p-value from a binomialtest 0.2005).

A.3.3. Manipulation Check: Responsibility for the Recipient

�e perceived responsibility was measured by using three statements: “Same level of respon-sibility as in the experiment before”, “More responsible as in the experiment before” and “Lessresponsible as in the experiment before”. Details are shown in Figure 20. In line with Hypoth-esis 1.i we expected the dictators in the SDT to feel less responsibility if the decision wouldbe made by a computer and not by themselves. As we see in Figure 20, these dictators indeedfelt signi�cantly less responsibility for the payo� of the recipient (p-value from a binomialtest 0.0000). In line with Hypothesis 1.ii we expected dictators in the CDT to feel less respon-sible once they can share the burden of their choice with a human instead of a computer andvice versa. Again, this was con�rmed by the results (see Figure 20) (p-value from a binomialtest 0.0009). Similarly, we expected dictators in the MDT to feel more responsible for thepayo� of the recipient once their human counterpart is replaced with a computer. �e e�ect,

35

Treatment

Resp

onsib

ility


less

sam

em

ore

A B A B A B

Figure 20: Change in personal responsibility for the recipient in the manipulation check bydictators


however, was only small and not signi�cant (p-value from a binomial test 0.2005).

A.3.4. Manipulation Check: Perceived Guilt

�e perceived guilt was measured as “Same level of guilt as in the experiment before”, “Moreguilt as in the experiment before” and “Less guilt as in the experiment before”. Details are shownin Figure 21. In line with Hypothesis 2.i we expected dictators in the SDT to feel less guiltywhen the actual decision is taken by a computer and not by the dictators. As we see in Figure21 the dictators felt indeed signi�cantly less guilty (p-value from a binomial test 0.0000).

In line with Hypothesis 2.ii we did expect dictators in the CDT to feel less guilty once theycan share the burden of their choice with a human instead of a computer and vice versa.Figure 21 shows such a tendency, but the e�ect is not signi�cant (p-value from a binomial test0.3269). Similarly, we expected dictators in the MDT to feel more guilty once their humancounterpart is replaced with a computer. However, this e�ect was also not signi�cant (p-value from a binomial test 0.0963).

A.4. Recipient: Further MeasurementsSimilar to the questions for the dictator(s) presented in Section A.1.2 we asked the recipientsin all treatments about their expectations regarding the dictators’ behavior and perceptionof responsibility and guilt. Even if these questions are not needed to answer our researchquestions the results might be interesting for others.

36

Treatment

Guilt


less

sam

em

ore

A B A B A B

Figure 21: Change in personal guilt in the manipulation check by dictators(�estion 3 from Section A.1.2)


Recipients were able to insert their assessment by a continuous scale from “Option A” (0)to “Option B” (100). A large proportion of the recipients in the CDT stated that they wouldexpect that the dictators choose Option A if they he would have had to decide on their own(see Figure 22). �is result was even slightly stronger in the MDT.

A.4.2. Expectation Regarding the Behavior of the Human Dictator(s) or Computer

�e expectation was measured by a continuous scale from “Player choose always Option A” (0)to “Player choose always Option B” (100). �e result is shown in Figure 23. Recipients in theSDT expected that the dictators choose Option B with a higher probability than recipients inthe MDT (p-value 0.0006). Furthermore, the recipients’ expectation regarding the choice ofthe human dictators in the MDT and in the CDT did not di�er signi�cantly (p-value 0.2191).

A.4.3. Assigned Responsibility for the Other Dictator and Recipient

�e assigned responsibility was measured by a continuous scale from “not responsible at all”(0) to “totally responsible” (100). Figure 24 shows, recipients did not expect that the dictatorwould perceive to be more or less responsible for the payo� of the other bene�ting dictatorin the MDT, where the other bene�ting dictator decided on her on, than in the CDT, wherethe decision of the other bene�ting dictator was made by a computer (p-value 0.3505).

However, as Figure 25 shows, recipients perceptions regarding the responsibility of thedictator for the recipients’ payo� di�ered between the treatments. While the assigned re-sponsibility did not di�er signi�cantly between the SDT and the MDT (p-value 0.2614), re-cipients perceived the dictator to be signi�cantly less responsible for their payo� in the CDT

37


Empi

rical

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computer multiple

Figure 22: Expectation of recipients for dictators who are deciding alone (as a hypotheticalsingle player)



Empi

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Figure 23: Expected human dictators’ choice by recipients(�estion 2 from Section A.1.2)

38

Responsibility

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Figure 24: Personal responsibility assigned to the dictator(s) for the active or passive dictatorby recipients


Responsibility

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Figure 25: Responsibility assigned to the dictator(s) for the recipient by recipients(�estion 6 from Section A.1.2)

39

Responsibility (according to recipients’s judgement)

Empi

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CDF

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…for passive dictator

0 20 40 60 80 100

…for recipient

responsibility of computer responsibility of human

Figure 26: Di�erence in responsibility assigned to the dictator(s) for the passive dictator andthe recipient by recipients

than in the MDT (p-value 0.0000).In addition, recipient in the CDT stated that they perceive a human dictator to be more

responsible for the �nal payo� of the passive dictator as well as for the payo� of the recipientthan a computer dictator, as shown in Figure 26.

A.5. Recipient: Manipulation CheckRecipients participating in the MDT [CDT] were asked to state how responsible and guiltydictators might perceive themselves to be for the �nal outcome if, contrary to the game theyjust played, they would have to decide together with a computer [another human]. Recipientsparticipating in SDT were asked to state how responsible they expect the dictators to perceivethemselves for the �nal outcome, if a computer would decide on their behalf.24

A.5.1. Manipulation Check: Assigned Responsibility to Human Dictator(s) andComputer

�e responsibility of the dictator for the �nal payo� as perceived by the recipients in themanipulation check is shown in Figure 27. Recipients in the SDT perceived the dictator to beless responsible if the decision would be made by a computer. Interestingly, recipients alsoperceived the dictator in the CDT to be signi�cantly less responsible for the �nal payo� ifshe would have to decide together with another human compared to dictators in the MDT,who would have to decide with a computer instead of another human (p-value 0.0149). Fora comparison of the relative changes in the recipients’ perception of the responsibility of

24For the wording of the manipulation check see Section A.1.2. It was the same as for the dictators.

40

Responsibility

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Figure 27: Expected human dictators’ personal responsibility in the manipulation check byrecipients


the dictator(s) for their own payo� in the hypothetical situation in the actual experiment bythe recipient see Figure 28. In line with Hypothesis 1.i , recipients in the SDT expected thedictator to feel less responsible if a computer would decide on her behalf (p-value 0.0000).However, contrary to Hypothesis 1.ii, recipients did not expect the dictators to feel signi�-cantly more responsible in the MDT when their counterpart would be replaced by a computer(p-value 0.5205). �e same applies for the CDT where recipients did not expect the dictatorsto feel responsible if their counterpart would be replaced by a human (p-value 0.1527).

�e responsibility assigned in the manipulation check to the other dictator (either hu-man or computer) perceived by the recipients is shown in Figure 29. Recipients in the SDTperceived the computer as signi�cantly more responsible than the recipient in the MDT (p-value 0.0031). As expected, recipients perceived the human dictator in the CDT to be moreresponsible for the �nal payo� than the computer dictator in the MDT (p-value 0.0001).

For a comparison of the relative change in the responsibility of the other dictator(s) be-tween the hypothetical situation and the actual experiment as perceived by the recipients seeFigure 30. Recipients in the MDT would perceive a computer dictator to be less responsiblethan a human dictator (p-value 0.0000). Correspondingly, recipient in the CDT also wouldperceive a human dictator to be signi�cantly more responsible than a computer dictator (p-value 0.0242).

A.5.2. Manipulation Check: Responsibility for the Other Dictator

�e perceived responsibility was measured from “Same level of responsibility as in the exper-iment before”, “More responsible as in the experiment before” and “Less responsible as in the

41


Empi

rical

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Figure 28: Change in personal responsibility assigned to the human dictator in the manipu-lation check by recipients

�e Figure shows the di�erence in the personal responsibility that the recipients expect the dictator(s) to per-ceive for their decision between the hypothetical situation (described in Section A.3) and the personal respon-sibility in the actual experiment (as shown in Figure 6).

Responsibility

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Figure 29: Expected responsibility assigned to a human or computer co-dictator in the ma-nipulation check by recipients


42

Di�erence in personal responsibility

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computer multiple

Figure 30: Di�erence in responsibility assigned to a computer or human co-dictator in themanipulation check by recipients

�e Figure shows the di�erence in the personal responsibility assigned by the recipients to the computer orhuman dictator between the hypothetical situation (described in Section A.3) and the actual experiment (asshown in Figure 6).

Treatment

Resp

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computer multiple

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Figure 31: Change in perceived personal responsibility of the dictator(s) for the active orpassive co-dictator in the manipulation check by recipients


43

Treatment

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Figure 32: Change in perceived personal responsibility of the dictator(s) for the recipient inthe manipulation check by recipients


experiment before”. Details are shown in Figure 31. Hypothesis 1.ii suggests that dictators inthe CDT who are confronted with a situation where they have to share their decision with ahuman instead of a computer would feel less responsible than before. �is is also expectedby recipients as Figure 31 shows (p-value from a binomial test 0.0000). Similarly we expecteddictators in the MDT who would have to share their decision with a computer would feelmore responsible. However, this can not be con�rmed based on the answers of the recipients(p-value 0.1435).


�e perceived responsibility was measured from “Same level of responsibility as in the exper-iment before”, “More responsible as in the experiment before” and “Less responsible as in theexperiment before”. In line with Hypothesis 1.i we expected dictators in the SDT to feel lessresponsibility when the decision is taken by a computer and not by the player herself. Re-cipients also expected that the dictator would feel signi�cantly less responsibility as Figure32 (p-value from a binomial test 0.0001).

Hypothesis 1.ii suggests that dictators in the CDT who would have to share their decisionwith a human instead of a computer would feel less responsible than before. However, thiswas not expected by recipients (p-value from a binomial test 0.2005). Similarly we expectedthat dictators in the MDT who now share their decision with a computer instead of anotherhuman would feel more responsible. �is was also not expected by the recipients (p-value0.0636).

44

Treatment

Guilt


less

sam

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ore

Figure 33: Change in perceived personal guilt of the dictator(s) in the manipulation check byrecipient



�e perceived guilt was measured as “Same level of guilt as in the experiment before”, “Moreguilt as in the experiment before” and “Less guilt as in the experiment before”. In line withHypothesis 2.i we expected dictators in the SDT to feel less guilty when the decision is takenby a computer and not by the dictator herself. �is was also expected by the recipients asFigure 33 shows (p-value from a binomial test 0.0000).

In line with Hypothesis 2.ii we expected dictators in the CDT to feel less guilty once theycan share the burden of their choice with a human. Figure 33 shows that such a tendency wasalso expected by the recipients, but the e�ect is not signi�cant (p-value from a binomial test0.0576). Similarly, we expected dictators in the MDT to feel more guilty once their humancounterpart is replaced with a computer. However, this was not expected by the recipients(p-value from a binomial test 1.0000).

A.6. Passive dictator: Further MeasurementsSimilar to the questions for the dictators presented in Section A.1.2 we asked the passive dic-tators in the CDT about their expectations regarding the dictators’ behavior and perceptionof responsibility and guilt. Even if these questions are not necessary to our research questionthe results may be interesting for others.


Passive dictators were able to insert their assessment by a continuous scale from “Option A”(0) to “Option B” (100). A large proportion of the passive dictators stated that they expect

45


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computer

Figure 34: Expectation of passive dictators for dictators who are deciding alone (as a hypo-thetical single player)


that the dictators choose Option A if they would have to decide on their own as Figure 34shows.

A.6.2. Expectation Regarding the Behavior of the Dictator(s)

�e expectation was measured by a continuous scale from “Player choose always A” (0) to“Player choose always B” (100). A large proportion of the passive dictators stated that theywould expect the dictator to choose Option A as Figure 35 shows.

A.6.3. Assigned Responsibility for the Decision to the Dictator(s) and theComputer

�e assigned responsibility was measured by a continuous scale from “not responsible atall” (0) to “totally responsible” (100). Figure 36 shows how responsible the passive dictatorsperceived the dictator to be for the �nal outcome in the CDT. A large proportion of thepassive dictators perceived the dictator to be very responsible for the �nal decision.

Figure 37 shows how responsible the passive dictators perceived the computer to be forthe �nal decision in the CDT. �ere is no detectable evidence of any trend.

However, by looking at the di�erence between the responsibility assigned to the dictatorand to the computer it becomes clear that a large proportion of the passive dictators hold thedictator as far more responsible for the �nal outcome than the computer (see Figure 38).

46


Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 35: Expected human dictators’ choice by passive dictators(�estion 2 from Section A.1.2)

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 36: Personal responsibility assigned to the human dictator by passive dictators(�estion 9 from Section A.1.2)

47

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 37: Responsibility assigned to the computer dictator by passive dictators(�estion 9 from Section A.1.2)


Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-50 0 50 100

computer

Figure 38: Di�erence between the personal responsibility assigned to the dictator and theresponsibility assigned to the computer co-dictator by passive dictators

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Responsibility

Empi

rical

CDF

0.0

0.2

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0.6

0.8

1.0

20 40 60 80 100

computer

Figure 39: Personal responsibility assigned to the human dictator for the passive dictator bypassive dictators


A.6.4. Assigned Responsibility for the Other Dictator and Recipient

�e assigned responsibility was measured by a continuous scale from “not responsible at all”(0) to “totally responsible” (100). A large proportion of the passive dictators stated that theyhold the dictator as very responsible for the payo� they receive as Figure 39 shows.

�e result of the responsibility assigned by the passive dictators to the computer is shownin Figure 40. A large proportion of the passive dictators stated that they hold the computeralso responsible for the the payo� they receive.

By looking at the di�erence between the responsibility assigned to the dictator and to thecomputer it becomes clear that a large proportion of the passive dictators hold the humandictator more responsible for their payo� than the computer as shown in Figure 41. However,the di�erence is not signi�cant (p-value 0.0797).

�e result for the responsibility assigned by the passive dictators for the recipients’ payo�to the dictator is shown in Figure 42.

�e result for the responsibility a�ributed to the computer is shown in Figure 43. A largeproportion of the passive dictators stated that they hold the dictator as very responsible andthe computer as responsible for the �nal payo� the recipient receives.

By looking at the di�erence between the responsibility for the payo� of the recipient at-tributed to the dictator and to the computer by the passive dictator (see Figure 44) it becomesclear that a large proportion of the passive dictators hold the dictator more responsible forthe payo� of the recipient than the computer (p-value 0.0060).

49

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 40: Responsibility assigned to the computer for the passive dictator by passivedictators



Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-50 0 50 100

computer

Figure 41: Di�erence between the personl responsibility assigned to the human dictator andthe responsibility assigned to the computer for the passive dictator by passivedictators

50

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

20 40 60 80 100

computer

Figure 42: Personal responsibility assigned to the human dictator for the recipient by passivedictators


Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 43: Responsibility assigned to the computer for the recipient by passive dictators(�estion 6 from Section A.1.2)

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Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-50 0 50 100

computer

Figure 44: Di�erence in responsibility assigned to the human dictator and to the computerfor the recipient by passive dictators

Guilt

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 45: Expected personal guilt of the dictator(s) by passive dictators(�estion 8 from Section A.1.2)

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Responsibility

Empi

rical

CDF

0.0

0.2

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0.6

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1.0

0 20 40 60 80 100

computer

Figure 46: Expected human dictators’ personal responsibility in the manipulation check bypassive dictators


A.6.5. Assigned Guilt

�e perceived guilt was measured by a continuous scale from “not guilty at all” (0) to “totallyguilty” (100). �e a�ributed guilt to the dictator seems to be distributed more or less equallywith no trend identi�able as shown in Figure 45.

A.7. Passive dictator: Manipulation CheckPassive dictators participating in the CDT were asked to state how responsible and guiltythey think the dictator might perceive themselves for the outcome if, contrary to the gamejust played, the dictator would have to decide together with a another human instead of acomputer.25

A.7.1. Manipulation Check: Assigned Responsibility to human Dictator(s) andComputer

How responsible the passive dictators expected the dictators to feel for the outcome in themanipulation check is shown in Figure 46.

For a comparison of the relative changes between the responsibility expected by the pas-sive dictator to be perceived by the dictator(s) for the outcome in the hypothetical situationand in the actual experiment see Figure 47. A large proportion of the passive dictators ex-pected the dictators to perceive themselves as less responsible if their counterpart is a humaninstead of a computer, however, the di�erence is not signi�cant (p-value 0.0691).

25�e wording of the manipulation check was the same as for recipients.

53


Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-60 -40 -20 0 20 40

computer

Figure 47: Change in personal responsibility assigned to the human dictator in the manipu-lation check by passive dictators

�e Figure shows the di�erence in the personal responsibility that the passive dictator expect the dictator toperceive for the decision between the hypothetical situation (described in Section A.3) and the actual experiment(as shown in Figure 38).

Responsibility

Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

0 20 40 60 80 100

computer

Figure 48: Expected personal responsibility assigned to a human co-dictator in the manipu-lation check by passive dictators


54


Empi

rical

CDF

0.0

0.2

0.4

0.6

0.8

1.0

-50 0 50 100

computer

Figure 49: Di�erence in responsibility assigned a computer or human co-dictator in the ma-nipulation check by passive dictators

�e Figure shows the di�erence in the personal responsibility assigned by the passive dictator to the humandictator between the hypothetical situation (described in Section A.3) and the actual experiment (as shown inFigure 38).

�e responsibility expected by the passive dictators to be perceived by the now humandictator for the �nal payo� in the manipulation check is shown in Figure 48. Passive dictatorsperceived the human dictator in the CDT to be very responsible for the �nal payo�.

For a comparison of the relative changes in the responsiblility assigned between the hu-man dictator(s) in the hypothetical situation and the computer in the actual experiment seeFigure 49. It can be seen clearly, that passive dictators perceived a human dictator to be moreresponsible for the �nal decision than a computer (p-value 0.0002).

A.7.2. Manipulation Check: Responsibility for the Passive Dictator

�e perceived responsibility was measured from “Same level of responsibility as in the ex-periment before”, “More responsible as in the experiment before” and “Less responsible as in theexperiment before”. Hypothesis 1.ii would suggest that dictators in the CDT who would sharetheir decision with a human instead of a computer would feel less responsible than beforefor the payo� of the other dictator as Figure 50 shows. �is was also expected by the passivedictators (p-value from a binomial test 0.0003).


�e perceived responsibility was measured from “Same level of responsibility as in the exper-iment before”, “More responsible as in the experiment before” and “Less responsible as in theexperiment before”. Hypothesis 1.ii suggests that dictators in the CDT who share their deci-sion with a human instead of a computer feel less responsible than before for the payo� of

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Treatment

Resp

onsib

ility

computer

less

sam

em

ore

Figure 50: Change in the perceived personal responsibility of the dictator for the passive co-dictator in the manipulation check by passive dictators


Treatment

Resp

onsib

ility

computer

less

sam

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ore

Figure 51: Change in perceived personal responsibility of the dictator for the recipient in themanipulation check by passive dictators


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Treatment

Guilt

computer

less

sam

em

ore

Figure 52: Change in perceived personal guilt of the dictator in the manipulation check bypassive dictators


the recipient. �is was also expected by the passive dictators as Figure 51 shows (p-valuefrom a binomial test 0.0079).


�e perceived guilt was measured as “Same level of guilt as in the experiment before”, “Moreguilt as in the experiment before” and “Less guilt as in the experiment before”. Details areshown in Figure 52. In line with Hypothesis 2.ii dictators in the CDT were expected to feelless guilty once they can share the burden of their choice with a human as Figure 52 shows.�is was also expected by the passive dictators (p-value from a binomial test 0.0005).

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'Sharing Responsibility with a Machine'Latane and Nida, 1981) as well as the perceived guilt (see...

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Transcript of 'Sharing Responsibility with a Machine'Latane and Nida, 1981) as well as the perceived guilt (see...