arXiv subjects

Valerio Capraro

Publications and source records attributed to Valerio Capraro.

At least 37 records · Page 2Linked to original sources

arXiv2020

The effect of nudging personal and injunctive norms on the trade-off between objective equality and efficiency

We report three pre-registered studies (total N=1,799) exploring the effect of nudging personal and injunctive norms in decisions that involve a trade-off between objective equality and efficiency. The first two studies provide evidence that: (i) nudging the personal norm has a similar effect to nudging the injunctive norm; (ii) when both norms are nudged towards the same direction, there is no additive effect; (iii) when the personal norm and the injunctive norm are nudged towards opposite directions, some people tend to follow the personal norm, while others tend to follow the injunctive norm. Study 3 tests whether these two classes of people, those who tend to follow the injunctive norm and those who tend to follow the personal norm, map onto the two sub-dimensions of Aquino and Reed's moral identity scale. We find partial evidence of this hypothesis: people higher in the symbolisation dimension are weakly more likely to follow the injunctive norm; however, we do not find any evidence that people higher in the internalisation dimension are more likely to follow the personal norm.

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arXiv2020

The evolution of trust and trustworthiness

Trust and trustworthiness form the basis for continued social and economic interactions, and they are also fundamental for cooperation, fairness, honesty, and indeed for many other forms of prosocial and moral behavior. However, trust entails risks, and building a trustworthy reputation requires effort. So how did trust and trustworthiness evolve, and under which conditions do they thrive? To find answers, we operationalize trust and trustworthiness using the trust game with the trustor's investment and the trustee's return of the investment as the two key parameters. We study this game on different networks, including the complete network, random and scale-free networks, and in the well-mixed limit. We show that in all but one case the network structure has little effect on the evolution of trust and trustworthiness. Specifically, for well-mixed populations, lattices, random and scale-free networks, we find that trust never evolves, while trustworthiness evolves with some probability depending on the game parameters and the updating dynamics. Only for the scale-free network with degree non-normalized dynamics, we find parameter values for which trust evolves but trustworthiness does not, as well as values for which both trust and trustworthiness evolve. We conclude with a discussion about mechanisms that could lead to the evolution of trust and outline directions for future work.

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arXiv2020

Priming reasoning increases intentions to wear a face covering to slow down COVID-19 transmission

Finding mechanisms to promote the use of face masks is fundamental during the second phase of the COVID-19 pandemic response, when shelter-in-place rules are relaxed and some segments of the population are allowed to circulate more freely. Here we report three pre-registered studies (total N = 1,920), using an heterogenous sample of people living in the USA, showing that priming people to "rely on their reasoning" rather than to "rely on their emotions" significantly increases their intentions to wear a face covering. Compared to the baseline, priming reasoning promotes intentions to wear a face covering, whereas priming emotion has no significant effect. These findings have theoretical and practical implications. Practically, they offer a simple and scalable intervention to promote intentions to wear a face mask. Theoretically, they shed light on the cognitive basis of intentions to wear a face covering.

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arXiv2020

The effect of norm-based messages on reading and understanding COVID-19 pandemic response governmental rules

The new coronavirus disease (COVID-19) threatens the lives of millions of people around the world, making it the largest health threat in recent times. Billions of people around the world are asked to adhere to strict shelter-in-place rules, finalised to slow down the spread of the virus. Appeals and messages are being used by leaders and policy-makers to promote pandemic response. Given the stakes at play, it is thus important for social scientists to explore which messages are most effective in promoting pandemic response. In fact, some papers in the last month have explored the effect of several messages on people's intentions to engage in pandemic response behaviour. In this paper, we make two contributions. First, we explore the effect of messages on people's actual engagement, and not on intentions. Specifically, our dependent variables are the level of understanding of official COVID-19 pandemic response governmental informative panels, measured through comprehension questions, and the time spent on reading these rules. Second, we test a novel set of appeals built through the theory of norms. One message targets the personal norm (what people think is the right thing to do), one targets the descriptive norm (what people think others are doing), and one targets the injunctive norm (what people think others approve or disapprove of). Our experiment is conducted online with a representative (with respect to gender, age, and location) sample of Italians. Norms are made salient using a flier. We find that norm-based fliers had no effect on comprehension and on time spent on the panels. These results suggest that norm-based interventions through fliers have very little impact on people's reading and understanding of COVID-19 pandemic response governmental rules.

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arXiv2020

The effect of messaging and gender on intentions to wear a face covering to slow down COVID-19 transmission

Now that various countries are or will soon be moving towards relaxing shelter-in-place rules, it is important that people use a face covering, to avoid an exponential resurgence of the spreading of the coronavirus disease (COVID-19). Here we report a pre-registered online experiment (N=2,459) using a heterogenous, although not representative, sample of people living in the USA, where we test the relative effect of messages highlighting that the coronavirus is a threat to "you" vs "your family" vs "your community" vs "your country" on self-reported intentions to wear a face covering. Results show that focusing on "your community" promotes intentions to wear a face covering relative to the baseline; the trend is the same when comparing "your community" to the other conditions, but not significant. We also conducted pre-registered analyses of gender differences on intentions to wear a face covering. We find that men less than women intend to wear a face covering, but this difference almost disappears in counties where wearing a face covering is mandatory. We also find that men less than women believe that they will be seriously affected by the coronavirus, and this partly mediates gender differences in intentions to wear a face covering (this is particularly ironic because official statistics actually show that men are affected by the COVID-19 more seriously than women). Finally, we also find gender differences in self-reported negative emotions felt when wearing a face covering. Men more than women agree that wearing a face covering is shameful, not cool, a sign of weakness, and a stigma; and these gender differences also mediate gender differences in intentions to wear a face covering.

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arXiv2020

Does observability amplify sensitivity to moral frames? Evaluating a reputation-based account of moral preferences

A growing body of work suggests that people are sensitive to moral framing in economic games involving prosociality, suggesting that people hold moral preferences for doing the "right thing". What gives rise to these preferences? Here, we evaluate the explanatory power of a reputation-based account, which proposes that people respond to moral frames because they are motivated to look good in the eyes of others. Across two pre-registered experiments (total N = 3,610), we investigated whether reputational incentives amplify sensitivity to framing effects. Both experiments manipulated (i) whether moral or neutral framing was used to describe a Trade-Off Game (in which participants chose between prioritizing equality or efficiency) and (ii) whether Trade-Off Game choices were observable to a social partner in a subsequent Trust Game. We find that framing effects are relatively insensitive to reputational incentives: observability did not significantly amplify sensitivity to moral framing. However, our results are not inconsistent with the possibility that observability has some amplification effect; quantitatively, the observed framing effect was 74% as large when decisions were private as when they were observable. These results suggest that moral frames may tap into moral preferences that are relatively deeply internalized, and that power of moral frames to promote prosociality may not be strongly enhanced by making the morally-framed behavior observable to others.

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arXiv2020

"Do the Right Thing" for Whom? An Experiment on Ingroup Favouritism, Group Assorting and Moral Suasion

In this paper we investigate the effect of moral suasion on ingroup favouritism. We report a well-powered, pre-registered, two-stage 2x2 mixed-design experiment. In the first stage, groups are formed on the basis of how participants answer to a set of questions, concerning non-morally relevant issues in one treatment (assorting on non-moral preferences), and morally relevant issues in another treatment (assorting on moral preferences). In the second stage, participants choose how to split a given amount of money between participants of their own group and participants of the other group, first in the baseline setting and then in a setting where they are told to do what they believe to be morally right (moral suasion). Our main results are: (i) in the baseline, participants tend to favour their own group to a greater extent when groups are assorted according to moral preferences, compared to when they are assorted according to non-moral preferences; (ii) the net effect of moral suasion is to decrease ingroup favouritism, but there is also a non-negligible proportion of participants for whom moral suasion increases ingroup favouritism; (iii) the effect of moral suasion is substantially stable across group assorting and four pre-registered individual characteristics (gender, political orientation, religiosity, pro-life vs pro-choice ethical convictions).

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arXiv2020

Lying on networks: The role of structure and topology in promoting honesty

Lies can have a negating impact on governments, companies, and the society as a whole. Understanding the dynamics of lying is therefore of crucial importance across different fields of research. While lying has been studied before in well-mixed populations, it is a fact that real interactions are rarely well-mixed. Indeed, they are usually structured and thus best described by networks. Here we therefore use the Monte Carlo method to study the evolution of lying in the sender-receiver game in a one-parameter family of networks, systematically covering complete networks, small-world networks, and one-dimensional rings. We show that lies which benefit the sender at a cost to the receiver, the so-called black lies, are less likely to proliferate on networks than they do in well-mixed populations. Honesty is thus more likely to evolve, but only when the benefit for the sender is smaller than the cost for the receiver. Moreover, this effect is particularly strong in small-world networks, but less so in the one-dimensional ring. For lies that favor the receiver at a cost to the sender, the so-called altruistic white lies, we show that honesty is also more likely to evolve than it is in well-mixed populations. But contrary to black lies, this effect is more expressed in the one-dimensional ring, whereas in small-world networks it is present only when the cost to the sender is greater than the benefit for the receiver. Lastly, for lies that benefit both the sender and the receiver, the so-called Pareto white lies, we show that the network structure actually favors the evolution of lying, but this only when the benefit for the sender is slightly greater than the benefit for the receiver. In this case again the small-world topology acts as an amplifier of the effect, while other network topologies fail to do the same.

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arXiv2019

Preferences for efficiency, rather than preferences for morality, drive cooperation in the one-shot Stag-Hunt Game

Recent work highlights that cooperation in the one-shot Prisoner's dilemma (PD) is primarily driven by moral preferences for doing the right thing, rather than social preferences for equity or efficiency. By contrast, little is known on what motivates cooperation in the Stag-Hunt Game (SHG). Cooperation in the SHG fundamentally differs from cooperation in the PD in that it is not costly, but risky: players have no temptation to deviate from the cooperative outcome, but cooperation only pays off if the other player cooperates. Here, we provide data from a large (N=436), pre-registered, experiment. Contrary to what has been observed for the PD, we find that SHG cooperation is primarily driven by preferences for efficiency, rather than preferences for doing the right thing.

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arXiv2019

On the heterogeneity of people's (dis)honest behavior along two dimensions: Cost of lying and cost of acquiring information

This paper studies lying in a novel context. Previous work has focused on situations in which people are either fully aware of the economic consequences of all available actions (e.g., die-under-cup paradigm), or they are uncertain, but this uncertainty cannot be cleared in any way (e.g., sender-receiver game). On the contrary, in reality, people oftentimes know that they will have a chance to lie, they are initially uncertain about the economic consequences of the available actions, but they can invest resources (e.g., time) to find them out. Here we capture the essence of this type of situations by means of a novel decision problem. Two experiments provide evidence of four empirical regularities regarding the distribution of choices, and suggest that participants vary along two dimensions: the moral cost of lying, and the cost of investing time to find out the payoffs associated to the available actions. Taking inspiration from these observations, we introduce a model that is consistent with the main empirical results.

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arXiv2019

The evolution of lying in well-mixed populations

Lies can have profoundly negative consequences for individuals, groups, and even for societies. Understanding how lying evolves and when it proliferates is therefore of significant importance for our personal and societal well-being. To that effect, we here study the sender-receiver game in well-mixed populations with methods of statistical physics. We use the Monte Carlo method to determine the stationary frequencies of liars and believers for four different lie types. We consider altruistic white lies that favor the receiver at a cost to the sender, black lies that favor the sender at a cost to the receiver, spiteful lies that harm both the sender and the receiver, and Pareto white lies that favor both the sender and the receiver. We find that spiteful lies give rise to trivial behavior, where senders quickly learn that their best strategy is to send a truthful message, whilst receivers likewise quickly learn that their best strategy is to believe the sender's message. For altruistic white lies and black lies, we find that most senders lie while most receivers do not believe the sender's message, but the exact frequencies of liars and non-believers depend significantly on the payoffs, and they also evolve non-monotonically before reaching the stationary state. Lastly, for Pareto white lies we observe the most complex dynamics, with the possibility of both lying and believing evolving with all frequencies between 0 and 1 in dependence on the payoffs. We discuss the implications of these results for moral behavior in human experiments.

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arXiv2019

The Effect of Social Information in the Dictator Game with a Taking Option

We experimentally study how redistribution choices are affected by positive and negative information regarding the behaviour of a previous participant in a dictator game with a taking option. We use the strategy method to identify behavioural "types", and thus distinguish "conformists" from "counter-conformists", and unconditional choosers. Unconditional choosers make up the greatest proportion of types (about 80%) while only about 20% of subjects condition their responses to social information. We find that both conformity and counter-conformity are driven by a desire to be seen as moral (the "symbolization" dimension of moral identity). The main difference is that, conformity is also driven by a sensitivity to what others think ("attention to social comparison"). Unconditional giving (about 30% of players) on the other hand is mainly driven by the centrality of moral identity to the self (the "internalization" dimension of moral identity). Social information thus seems to mainly affect those who care about being seen to be moral. The direction of effect however depends on how sensitive one is to what others think.

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arXiv2019

Increasing altruistic and cooperative behaviour with simple moral nudges

The conflict between pro-self and pro-social behaviour is at the core of many key problems of our time, as, for example, the reduction of air pollution and the redistribution of scarce resources. For the well-being of our societies, it is thus crucial to find mechanisms to promote pro-social choices over egoistic ones. Particularly important, because cheap and easy to implement, are those mechanisms that can change people's behaviour without forbidding any options or significantly changing their economic incentives, the so-called "nudges". Previous research has found that moral nudges (e.g., making norms salient) can promote pro-social behaviour. However, little is known about whether their effect persists over time and spills across context. This question is key in light of research showing that pro-social actions are often followed by selfish actions, thus suggesting that some moral manipulations may backfire. Here we present a class of simple moral nudges that have a great positive impact on pro-sociality. In Studies 1-4 (total N = 1,400), we use economic games to demonstrate that asking subjects to self-report "what they think is the morally right thing to do" does not only increase pro-sociality in the choice immediately after, but also in subsequent choices, and even when the social context changes. In Study 5, we explore whether moral nudges promote charity donations to humanitarian organisations in a large (N=1,800) crowdfunding campaign. We find that, in this context, moral nudges increase donations by about 44 percent.

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arXiv2019

Shall we turn off the media? Global information can destroy local cooperation in the one-dimensional ring

In this paper we investigate the evolution of cooperation when the interaction structure is strictly local, and hence fitness only depends on local behaviors, while the competition structure is partly global, and hence selection can happen also between distant agents. We explore this novel setup by means of numerical simulations in a model where agents are arranged in a one-dimensional ring. Preliminary results suggest that the extent of global comparison systematically favors defection under strong selection, while its effect under weak selection is less systematic, but overall still favors defection. Further, the extent of global comparison seems to reduce sensibly fixation times.

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arXiv2019

Gender differences in the equity-efficiency trade-off

Gender differences in human behaviour have attracted generations of social scientists, who have explored whether males and females act differently in domains involving competition, risk taking, cooperation, altruism, honesty, as well as many others. Yet, little is known about gender differences in the equity-efficiency trade-off. It has been suggested that females are more equitable than males, but the empirical evidence is weak and inconclusive. This gap is particularly important, because people in power of redistributing resources often face a conflict between equity and efficiency, to the point that this trade-off has been named as "the central problem in distributive justice". The recently introduced Trade-Off Game (TOG) - in which a decision-maker has to unilaterally choose between being equitable or being efficient - offers a unique opportunity to fill this gap. To this end, I analyse gender differences on a large dataset including all N=5,056 TOG decisions collected by my research group since we introduced this game. The results show that females prefer equity over efficiency to a greater extent than males do. These findings suggest that males and females have different preferences for resource distribution, and point to new avenues for future research.

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arXiv2019

Priming intuition disfavors instrumental harm but not impartial beneficence

Understanding the cognitive underpinnings of moral judgment is one of most pressing problems in psychological science. Some highly-cited studies suggest that reliance on intuition decreases utilitarian (expected welfare maximizing) judgments in sacrificial moral dilemmas in which one has to decide whether to instrumentally harm (IH) one person to save a greater number of people. However, recent work suggests that such dilemmas are limited in that they fail to capture the positive, defining core of utilitarianism: commitment to impartial beneficence (IB). Accordingly, a new two-dimensional model of utilitarian judgment has been proposed that distinguishes IH and IB components. The role of intuition on this new model has not been studied. Does relying on intuition disfavor utilitarian choices only along the dimension of instrumental harm or does it also do so along the dimension of impartial beneficence? To answer this question, we conducted three studies (total N = 970, two preregistered) using conceptual priming of intuition versus deliberation on moral judgments. Our evidence converges on an interaction effect, with intuition decreasing utilitarian judgments in IH - as suggested by previous work - but failing to do so in IB. These findings bolster the recently proposed two-dimensional model of utilitarian moral judgment, and point to new avenues for future research.

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arXiv2019

The power of moral words: Loaded language generates framing effects in the extreme dictator game

Understanding whether preferences are sensitive to the frame has been a major topic of debate in the last decades. For example, several works have explored whether the dictator game in the give frame gives rise to a different rate of pro-sociality than the same game in the take frame, leading to mixed results. Here we contribute to this debate with two experiments. In Study 1 ($N=567$) we implement an extreme dictator game in which the dictator either gets \$0.50 and the recipient gets nothing, or the opposite (i.e., the recipient gets \$0.50 and the dictator gets nothing). We experimentally manipulate the words describing the available actions using six terms, from very negative (e.g., stealing) to very positive (e.g., donating) connotations. We find that the rate of pro-sociality is affected by the words used to describe the available actions. In Study 2 ($N=221$) we ask brand new participants to rate each of the words used in Study 1 from ``extremely wrong'' to ``extremely right'' . We find that these moral judgments explain the framing effect in Study 1. In sum, our studies provide evidence that framing effects in an extreme Dictator game can be generated using morally loaded language.

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arXiv2019

Time pressure and honesty in a deception game

Previous experiments have found mixed results on whether honesty is intuitive or requires deliberation. Here we add to this literature by building on prior work of Capraro (2017). We report a large study (N=1,389) manipulating time pressure vs time delay in a deception game. We find that, in this setting, people are more honest under time pressure, and that this result is not driven by confounds present in earlier work.

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