Behavior In Ultimatum Game Research Articles

Do self-talk phrases affect behavior in ultimatum games?

The current study investigates whether self-talk phrases can influence behavior in Ultimatum Games. In our three self-talk treatments, participants were instructed to tell themselves (i) to keep their own interests in mind, (ii) to also think of the other person, or (iii) to take some time to contemplate their decision. We investigate how such so-called experimenter-determined strategic self-talk phrases affect behavior and emotions in comparison to a control treatment without instructed self-talk. The results demonstrate that other-focused self-talk can nudge proposers towards fair behavior, as offers were higher in this group than in the other conditions. For responders, self-talk tended to increase acceptance rates of unfair offers as compared to the condition without self-talk. This effect is significant for both other-focused and contemplation-inducing self-talk but not for self-focused self-talk. In the self-focused condition, responders were most dissatisfied with unfair offers. These findings suggest that use of self-talk can increase acceptance rates in responders, and that focusing on personal interests can undermine this effect as it negatively impacts the responders’ emotional experience. In sum, our study shows that strategic self-talk interventions can be used to affect behavior in bargaining situations.

Ultimatum Game Behavior in a Social-Preferences Vacuum Chamber

We study strategic interaction in an experimental social-preferences vacuum chamber. We mute social preferences by letting participants knowingly interact with computers. Our new design allows for indirect strategic interaction: there are several waves in which computer players inherit the behavior of human players from the previous wave. We apply our method to investigate trembling-hand perfection in a normal-form version of the ultimatum game. We find that behavior remains far off from a trembling-hand perfect equilibrium under selfish preferences even towards the end of our experiment. The likely reasons for our findings are strategic uncertainty and incomplete learning.

Social Preferences and Environmental Behavior: A Comparison of Self-Reported and Observed Behaviors

Faced with the depletion of natural resources and climate change, individuals making the choice to behave in a more environmentally conscious way is increasingly necessary. Rational choice theory suggests that individuals will only behave in pro-environmental ways if they perceive those actions to align with their own self-interests. Others, however, have highlighted instances where individuals act pro-socially or altruistically, deviating from their own self-interests for the benefit of others. The present study examines whether individuals’ social preferences are associated with engagement in pro-environmental behaviors. Specifically, drawing on a methodology from behavioral economics, we use dictator and ultimatum game behavior to measure social preferences, and we then evaluate whether heterogeneity in social preferences is associated with self-reported pro-environmental behaviors and observed recycling behavior. The results indicate that individual differences in social preferences have a modest association with self-reported pro-environmental behaviors but no association with observed recycling behavior. Self-reported pro-environmental behavior was not associated with observed recycling behavior. We also find that recycling bin proximity to classroom doors increased participation in recycling. This finding demonstrates that individuals are receptive to the proximate opportunity to recycle. This suggests increasing the ease with which people can engage in pro-environmental behaviors, such as recycling, will promote participation in these practices. Overall, our research indicates that social preferences do not seem to drive individuals to act in environmentally friendly ways. This work also provides new opportunities for future research to integrate economic games into the study of pro-environmental behaviors.

Neural Correlates of Self-Construal Priming in the Ultimatum Game.

Research from cultural and social psychology has identified a central role of self-construal, or the way one views themselves in relation to others, in social cognition. Accordingly, it is plausible that self-construal plays an instrumental role in important aspects of decision-making relating to fairness considerations. Prior research has shown that priming methodology is a useful tool to experimentally isolate the effect of self-construal on social decision-making processes. In the current study we investigated the neural effects of self-construal priming on fairness considerations, using an Ultimatum Game setup (N = 97). Based on previous findings, we predicted an interaction between the self-construal prime and gender on Ultimatum Game behavior; males primed with interdependence would reject the offer relatively more compared to independence, and vice versa for females. As previous neuro-imaging research has established an instrumental role of the anterior insula (AI) and ventromedial prefrontal cortex (vmPFC) in the rejection of unfair offers, we expected higher rejection rates to be mirrored by increased activity in these regions. However, the analyses did not confirm these predictions. As further inspection of the data revealed a habituation effect, we performed a follow-up analysis on the first block (N = 59). This subsequent analysis revealed that priming interdependence resulted in reduced AI activity compared to priming independence, although no behavioral differences were observed. The difference was theorized to result from motivations as conflict avoidance and harmony maintenance, commonly associated with interdependence. Furthermore, the analysis revealed greater vmPFC activity for females compared to males for rejected offers, although this effect was not robust when controlled for trait self-construal. These follow-up analyses suggest that self-construal priming influences insula activity, as well as implicating an underlying role of trait self-construal in observed gender differences in vmPFC activity relating to fairness considerations.

S243. Heightened Effect of Unfairness and no Effect of Oxytocin on Ultimatum Game Behavior in Schizophrenia

S243. Heightened Effect of Unfairness and no Effect of Oxytocin on Ultimatum Game Behavior in Schizophrenia

Social Versus Moral Preferences in the Ultimatum Game: A Theoretical Model and an Experiment

In the Ultimatum Game (UG) one player, named “proposer”, has to decide how to allocate a certain amount of money between herself and a “responder”. If the offer is greater than or equal to the responder’s minimum acceptable offer (MAO), then the money is split as proposed, otherwise, neither the proposer nor the responder get anything. The UG has intrigued generations of behavioral scientists because people in experiments blatantly violate the equilibrium predictions that self-interested proposers offer the minimum available non-zero amount, and self-interested responders accept. Why are these predictions violated? Previous research has mainly focused on the role of social preferences. Little is known about the role of general moral preferences for doing the right thing, preferences that have been shown to play a major role in other social interactions (e.g., Dictator Game and Prisoner’s Dilemma). Here I develop a theoretical model and an experiment designed to pit social preferences against moral preferences. I find that, although people recognize that offering half and rejecting low offers are the morally right things to do, moral preferences have no causal impact on UG behavior. The experimental data are indeed well fit by a model according to which: (i) high UG offers are motivated by inequity aversion and, to a lesser extent, self-interest; (ii) high MAOs are motivated by inequity aversion.

No Robust Association between Static Markers of Testosterone and Facets of Socio-Economic Decision Making.

Digit ratio (2D:4D) and facial width-to-height ratio (WHR) are supposedly static indicators of testosterone exposition during prenatal and pubertal lifetime, respectively. Both measures have been linked to aggressive and assertive behavior in laboratory economic games, as well as in real world scenarios. Most of the research—often limited to male subjects—considers the associations between these behaviors, traits, and hormonal markers separately for 2D:4D and WHR. Reported associations are weak and volatile. In the present study we had independent raters assess 2D:4D and WHR in a sample of N = 175 participants who played the ultimatum game (UG). Respondent behavior in UG captures the tendency to reject unfair offers (negative reciprocity). If unfair UG offers are seen as provocations, then individuals with stronger testosterone exposition may be more prone to reject such offers. Economists argue that negative reciprocity reflects altruistic punishment, since the rejecting individual is sacrificing own resources. However, recent studies suggest that self-interest, in terms of status defense plays a substantial role in decisions to reject unfair offers. We also assessed social preferences by social value orientation and assertiveness via self-report. By applying structural equation modeling we estimated the latent level association of 2D:4D and WHR with negative reciprocity, assertiveness and prosociality in both sexes. Results revealed no robust association between any of the trait measures and hormonal markers. The measures of 2D:4D and WHR were not related with each other. Multigroup models based on sex suggested invariance of factor loadings allowing to compare hormone-behavior relationships of females and males. Only when collapsing across sex greater WHR was weakly associated with assertiveness, suggesting that individuals with wider faces tend to express greater status defense. Only the right hand 2D:4D was weakly associated with prosocial behavior, indicating that individuals with lower prenatal testosterone exposure are more cooperative. Rejection behavior in UG was not related with 2D:4D nor WHR in any of the models. There were also no curvilinear associations between 2D:4D and prosociality as theorized in the literature. Our results suggest that previous studies over-estimated the role of static markers of testosterone in accounting for aggression and competition behavior in males.

Learning (not) to yield: An experimental study of evolving ultimatum game behavior

Whether behavior converges toward rational play or fair play in repeated ultimatum games, depends on which player yields first. If responders conceded first by accepting low offers, proposers, would not need to learn to offer more. Play would thus converge toward unequal sharing. If proposers, learnt fast that low offers are doomed to be rejected and adjusted their offers accordingly, pressure, would be lifted from responders to learn to accept such offers. Play would thus converge toward equal, sharing. Here, we tested the hypothesis that it is regret—both material and strategic—which determines, how players adapt their behavior. We conducted a repeated ultimatum game experiment with, randomly changing strangers. One treatment offers players only feedback about the outcome of their, play. Another treatment offers additional information about the median outcomes in the population. We find that regret is a good predictor of the dynamics of play, in particular of proposer behavior., Except for a very short endgame phase, in which more tolerance of less equitable sharing surfaced, behavior converges toward equal sharing. Population information hardly speeds up this convergence.

How fairly do chimpanzees play the ultimatum game?

Humans can behave fairly, but can other species? Recently we tested chimpanzees on a classic human test for fairness, the Ultimatum Game, and found that they behaved similarly to humans. In humans, Ultimatum Game behavior is cited as evidence for a human sense of fairness. By that same logic, we concluded that chimpanzees behaved fairly in our recent study. However, we make a distinction between behavior and motivation. Both humans and chimpanzees behaved fairly, but determining why they did so is more challenging.

Ultimatum Game behavior in light of attachment theory

In this paper we import a mainstream psychological theory, known as attachment theory, into economics and show the implications of this theory for economic behavior by individuals in the ultimatum bargaining game. Attachment theory examines the psychological tendency to seek proximity to another person, to feel secure when that person is present, and to feel anxious when that person is absent. An individual’s attachment style can be classified along two-dimensional axes, one representing attachment “avoidance” and one representing attachment “anxiety”. Avoidant people generally feel discomfort when being close to others, have trouble trusting people and distance themselves from intimate or revealing situations. Anxious people have a fear of abandonment and of not being loved. Utilizing attachment theory, we evaluate the connection between attachment types and economic decision making, and find that in an Ultimatum Game both proposers’ and responders’ behavior can be explained by their attachment styles, as implied by the theory. We demonstrate how knowledge of the attachment type of the responder can be utilized by the proposer in order to maximize his expected income. We believe this theory has implications for economic behavior in different settings, such as negotiations, in general, and more specifically, may help explain behavior, and perhaps even anomalies, in other experimental settings.

Bargaining over waiting time in ultimatum game experiments

While preference-based explanations play an increasing role in economics and sociology, the accurate measurement of social preferences deserves more attention. Most laboratory experiments measure social preferences by studying the division of “a cake that nobody had to bake” (Güth and Kliemt, 2003). This article reports results of the first ultimatum game experiment with bargaining over waiting time. The experiment was created to avoid effects of windfall gains. In contrast to donated money, time is not endowed by the experimenter and implies a natural loss to subjects. This allows for a better measurement of the inherent conflict in the ultimatum game. We implemented three anonymity conditions; one baseline condition, one condition with anonymity among subjects and one double-blind condition in which the experimenter did not know the division of waiting time. While we expected to observe less other-regarding behavior in ultimatum game bargaining over time, our experimental results rather confirm previous ultimatum game experiments, in which people bargained over money. The modal offer was half of the waiting time and only one offer was rejected. Interestingly, anonymity did not change the results significantly. In conclusion, our experiment confirms other-regarding behavior in the ultimatum game.

The dynamics of responder behavior in ultimatum games: a meta-study

Using data aggregated from seven papers that study repeated play in standard ultimatum games with either stranger or absolute stranger matching, we show that the behavior of responders changes with experience. High offers are more likely to be accepted with experience and low offers are more likely to be rejected. At the individual level, there is a negative relationship between the likelihood that a given offer is accepted and the size of the preceding offer. We compare the results with predictions generated by static models of distributional preferences, implicitly dynamic models of preferences with reciprocity, and explicitly dynamic models of adaptive learning. The data is most consistent with models of preferences with reciprocity.

Interactive decision-making in people with schizotypal traits: A game theory approach

Studies that have investigated whether deficits in social cognition observed in schizophrenia are also present in schizotypal individuals have largely been inconclusive, and none of these studies have examined social interactive behavior. Here, we investigated interactive decision-making behavior in individuals differing in the amount of schizotypal symptoms using tasks derived from Game Theory. In total 1691 undergraduate students were screened with the Schizotypal Personality Questionnaire-Brief version. We selected 69 people distributed across the full schizotypal continuum to participate in Ultimatum and Dictator Games in which they played against human and non-human, computer partners. The results showed that higher levels of schizotypal symptoms, particularly positive and disorganized schizotypy, were related to proposing higher offers to all partners. Additionally, the amount of interpersonal schizotypal symptoms was associated with an increased acceptance rate of very unfair offers from human partners, possibly reflecting a blunted emotional response to such offers. We conclude that positive and disorganized schizotypal symptoms are associated with less adequate bargaining behavior, similar to what has been recently observed in patients with schizophrenia. The observed similarities on Ultimatum Game behavior between patients with schizophrenia and individuals with more schizotypal symptoms contribute to the growing evidence that social cognitive deficits may represent a marker of vulnerability to schizophrenia.

Bargaining Over Time in Ultimatum Game Experiments

We report the first ultimatum game experiment with bargaining over waiting time. The experiment was created to avoid effects of windfall gains. In contrast to donated money, time is not endowed by the experimenter and implies a natural loss to the subjects. This allows for a better measurement of the inherent conflict in the ultimatum game.We implemented three anonymity conditions; one baseline condition, one condition with anonymity among the subjects and one double-blind condition in which the experimenter did not know the division of waiting time. While we expected to observe less other-regarding behavior in ultimatum game bargaining over time, our experimental results rather confirm previous ultimatum game experiments, in which people bargained over money. The modal offer was half of the waiting time and only one offer was rejected. Interestingly, anonymity did not change the results significantly. In conclusion, our experiment confirms other-regarding behavior in the ultimatum game.

Personality and Birth Order in Monozygotic Twins Adopted Apart: A Test of Sulloway's Theory; Research Reviews: Twin Births and Cancer Risk in Mothers, Male Sexual Dysfunction, Twin Study of Ultimatum Game Behavior; Human Interest: ‘The Land of Twins’, Twin-Like Reunion-I, Twin-Like Reunion-II

A brief overview of Sulloway's (1996) theory of birth order and personality is presented. A reared apart twin approach for testing his personality findings regarding openness to experience and conscientiousness in first borns and later borns is described. This is followed by summaries of three recent twin studies. The topics include cancer risk in mother of twins, sexual dysfunction in males and responder behavior during ultimatum games. This article concludes with a discussion of twinning rates and rituals among the Yoruba of western Nigeria, and descriptions of two unusual reunions between siblings and twins.

Testing subgame perfection apart from fairness in ultimatum games

We present an experiment designed to separate the two commonplace explanations for behavior in ultimatum games—subjects’ concern for fairness versus the failure of subgame perfection as an equilibrium re…nement. We employ a tournament structure of the bargaining interaction to eliminate the potential for fairness to in‡uence behavior. Comparing the results

Advice and behavior in intergenerational ultimatum games: An experimental approach

In the real world, when people play a game, they often receive advice from those that have played it before them. Such advice can facilitate the creation of a convention of behavior. This paper studies the impact of advice on the behavior subjects who engage in a non-overlapping generational Ultimatum game where after a subject plays he is replaced by another subject to whom he can offer advice. Our results document the fact that allowing advice fosters the creation of a convention of behavior in Ultimatum games. In addition, by reading the advice offered we conclude that arguments of fairness are rarely used to justify the offers of Senders but are relied upon to justify rejections by Receivers.

What does the Ultimatum Game mean in the real world?

The predictive validity of the ultimatum game (UG) for cross-cultural differences in real-world behavior has not yet been established. We discuss results of a recent meta-analysis (Oosterbeek et al 2004), which examined UG behavior across large-scale societies and found that the mean percent offers rejected was positively correlated with social expenditure.

Relative versus Absolute Speed of Adjustment in Strategic Environments: Responder Behavior in Ultimatum Games

Learning models predict that the relative speed at which players in a game adjust their behavior has a critical influence on long term behavior. In an ultimatum game, the prediction is that proposers learn not to make small offers faster than responders learn not to reject them. We experimentally test whether relative speed of learning has the predicted effect, by manipulating the amount of experience accumulated by proposers and responders. The experiment allows the predicted learning by responders to be observed, for the first time.

Economic‐Psychological Reflections on Custom in the Economy

This comment is part of a symposium on Ekkehart Schlicht, On Custom in the Economy (1998)