Reciprocal trust mediates deep transfer of learning between games of strategic interaction

We studied transfer of learning across two games of strategic interaction. We found that the interpersonal relation between two players during and across two games influence development of reciprocal trust and transfer of learning from one game to another. We show that two types of similarities between the games affect transfer: (1) deep similarities facilitate transfer of an optimal solution across games; (2) surface similarities can either facilitate or hinder transfer depending on whether they lead players toward an optimal or sub-optimal solution in the target game. Learning an optimal solution in a context of interdependence between players is associated with development of reciprocal trust, which in turn mediates transfer of learning across games. The results can be used to inform the design of training exercises to develop strategic interaction skills.     

Facial dynamics as indicators of trustworthiness and cooperative behavior

Detecting cooperative partners in situations that have financial stakes is crucial to successful social exchange. The authors tested whether humans are sensitive to subtle facial dynamics of counterparts when deciding whether to trust and cooperate. Participants played a 2-person trust game before which the facial dynamics of the other player were manipulated using brief (<6 s) but highly realistic facial animations. Results showed that facial dynamics significantly influenced participants' (a) choice of with whom to play the game and (b) decisions to cooperate. It was also found that inferences about the other player's trustworthiness mediated these effects of facial dynamics on cooperative behavior.     

Hard and Soft Preparation Sets in Boolean Games

A fundamental problem in game theory is the possibility of reaching equilibrium outcomes with undesirable properties, e.g., inefficiency. The economics literature abounds with models that attempt to modify games in order to avoid such undesirable properties, for example through the use of subsidies and taxation, or by allowing players to undergo a bargaining phase before their decision. In this paper, we consider the effect of such transformations in Boolean games with costs, where players control propositional variables that they can set to true or false, and are primarily motivated to seek the satisfaction of some goal formula, while secondarily motivated to minimise the costs of their actions. We adopt (pure) preparation sets (prep sets) as our basic solution concept. A preparation set is a set of outcomes that contains for every player at least one best response to every outcome in the set. Prep sets are well-suited to the analysis of Boolean games, because we can naturally represent prep sets as propositional formulas, which in turn allows us to refer to prep formulas. The preference structure of Boolean games with costs makes it possible to distinguish between hard and soft prep sets. The hard prep sets of a game are sets of valuations that would be prep sets in that game no matter what the cost function of the game was. The properties defined by hard prep sets typically relate to goal-seeking behaviour, and as such these properties cannot be eliminated from games by, for example, taxation or subsidies. In contrast, soft prep sets can be eliminated by an appropriate system of incentives. Besides considering what can happen in a game by unrestricted manipulation of players’ cost function, we also investigate several mechanisms that allow groups of players to form coalitions and eliminate undesirable outcomes from the game, even when taxes or subsidies are not a possibility.     

Is behavioral pro-sociality game-specific? Pro-social preference and expectations of pro-sociality

We observed the behaviors of the same people across five games – two prisoner’s dilemma games, a trust game (in which the subject took on the role of both truster and trustee), a dictator game, and a faith game – any pair of which was separated by an interval of several months to reduce potential carry-over effects, and found strong consistency in behaviors among these games. We also found consistency between the expectations of other players’ behaviors and the player’s own behavior across games. We further found that the consistent behavioral pro-sociality observed across different games was related to the general measures of pro-social value orientation and perceiving the game situations. These findings suggest that individual and cultural differences in game behaviors can reflect both the ways in which people perceive game situations and their general social preferences.     

亲社会视频游戏中的合作对博弈决策中合作行为的影响

以38名大学生和研究生为被试,采用Chicken Game实验范式测量合作行为,考察了单人和双人合作模式游戏后,性别和游戏习惯对玩家在博弈决策中合作行为的影响。结果表明：（1）双人合作模式游戏可以促进玩家在博弈决策中的合作行为;（2）双人合作模式游戏后,男玩家（相比女玩家）在博弈决策中的合作行为更多;（3）玩游戏的习惯影响博弈决策中的合作行为,相比于经常习惯与现实朋友玩游戏和独自玩游戏的玩家,经常习惯与网友玩游戏的玩家在双人合作模式游戏后的合作行为更多。本研究不仅证实了一般学习模型,也证实了亲社会合作类视频游戏可以有效促进博弈决策中的合作行为。     

影响博弈结果的方法效应研究

最后通谍博弈和独裁者博弈是实验经济学的经典博弈,也被心理学家用来研究人的公平和利他行为。该研究考查了经济学和心理学通常的报酬支付方式、博弈中待分配的金额是否影响博弈结果,以及两个博弈进行组内实验时是否会产生顺序效应。结果发现支付方式和金额不影响博弈结果,但有顺序效应产生。该研究对国内研究者进一步借用这两个博弈的相关研究打下了一定的方法学基础。     

The Soritical Centipede

Two philosophical questions arise about rationality in centipede games that are logically prior to attempts to apply the formal tools of game theory to this topic. First, given that the players have common knowledge of mutual rationality and common knowledge that they are each motivated solely to maximize their own profits, is there a backwards‐induction argument that (i) employs only familiar non‐technical concepts about rationality, (ii) leads to the conclusion that the first player is rationally obligated to end the game at the first step, (iii) is deductively valid, (iv) employs premises all of which are prima facie highly plausible, and (v) is prima facie sound (in virtue of features (iii) and (iv))? Second, if there is such an argument, then is it actually sound, or is it instead defective somehow despite being prima facie sound? Addressing these two questions is our project. We present a backwards‐induction argument that is prima facie sound; we argue that it is an instance of the notorious sorites paradox, and hence that the concepts of rational obligatoriness and rational permissibility are vague; and we briefly address the potential consequences of all this for the foundations of game theory and decision theory.     

Short- and Long-Term Effects of Video Game Violence on Interpersonal Trust

Two studies investigate the psychological processes underlying short- and long-term effects of video game violence on interpersonal trust. Study 1 demonstrates that interacting with physically aggressive virtual agents decreases players' trust in subsequent interactions. This effect was stronger for players who were dispositionally sensitive to victimization. In Study 2, long-term effects of adolescents' frequent exposure to video game violence on interpersonal trust and victim sensitivity were investigated. Cross-lagged path analyses show that the reported frequency of playing violent video games reduced interpersonal trust over a period of 12 months, particularly among victim-sensitive players. These findings are in line with the sensitivity to mean intentions (SeMI) model, and they suggest that interpersonal mistrust is a relevant long-term outcome of frequent exposure to video game violence.     

Investor's Pessimistic and False Belief About Trustworthiness and Stake Size in Trust Decision1

Trust is a vital element of any society. Previous studies using trust games have provided insight into understandings of trusting behavior. However, investors' behaviors can be confounded by their risk preferences in the game, and little is known about the relationship between stake size and beliefs of others' good intentions underlying trust. We thus used a variant of the trust game and conducted two experiments to examine how stake size affects investors' beliefs about receivers' trustworthiness, with model-based analyses. We showed that, when holding all else equal, investors trusted more, but their expectations of reciprocation declined as stake size increased. However, actual receivers' reciprocation rates showed the opposite trend to investors' pessimistic beliefs. Furthermore, following previous studies in social psychology, we hypothesized that investors' social preferences (social value orientation) moderated the beliefs underlying trust, but they had no explanatory powers in investors' expectations of reciprocation. These results suggest that peoples' naive beliefs about stake size play a more important role in trust decisions than expected.     

Media violence and the self: The impact of personalized gaming characters in aggressive video games on aggressive behavior

A recent development in video games is that players can design and personalize their own in-game characters. It was predicted that this innovation could lead to elevations in the intensity of the psychological effects of video games. The present study confirmed this hypothesis, revealing that participants who played an aggressive video game using their own, personalized character exhibited higher levels of aggressive behavior than participants who played an aggressive game with a non-personalized character. The aggressive behavior levels of the own-character players also exceeded those of individuals who played a non-aggressive game, regardless of whether or not they used a personalized character. Process analyses revealed that participants playing a violent video game with a personalized game character experienced more arousal and self-activation than they did when playing with an impersonal, default game character, which in turn increased aggressive responses.     

Violent and nonviolent video games produce opposing effects on aggressive and prosocial outcomes

Experimental studies routinely show that participants who play a violent game are more aggressive immediately following game play than participants who play a nonviolent game. The underlying assumption is that nonviolent games have no effect on aggression, whereas violent games increase it. The current studies demonstrate that, although violent game exposure increases aggression, nonviolent video game exposure decreases aggressive thoughts and feelings (Exp 1) and aggressive behavior (Exp 2). When participants assessed after a delay were compared to those measured immediately following game play, violent game players showed decreased aggressive thoughts, feelings and behavior, whereas nonviolent game players showed increases in these outcomes. Experiment 3 extended these findings by showing that exposure to nonviolent puzzle-solving games with no expressly prosocial content increases prosocial thoughts, relative to both violent game exposure and, on some measures, a no-game control condition. Implications of these findings for models of media effects are discussed.     

Mutual support in games: Some properties of Berge equilibria

The Berge equilibrium concept formalizes mutual support among players motivated by the altruistic social value orientation in games. We prove some basic results for Berge equilibria and their relations to Nash equilibria, and we provide a straightforward method for finding Berge equilibria in n-player games. We explore some specific examples, and we explain how the Berge equilibrium provides a compelling model of cooperation in social dilemmas. We show that the Berge equilibrium also explains coordination in some common interest games and is partially successful in explaining the payoff dominance phenomenon, and we comment that the theory of team reasoning provides alternative solutions to these problems.     

Real brands in imaginary worlds: investigating players' experiences of brand placement in digital games

• This paper explores the development of brand placement in digital games using focus groups with game‐players. Growth in in‐game brand placement is explained by game developers' financial and creative priorities and experimentation in marketerss' use of media. The external context of game‐play is then examined based on explanations of the non‐material aspects of consumer behaviour. Internal game processes are also reviewed, including psychological processes that are likely to be of interest to marketers. The reported experiences of players are then considered in terms of these processes. Findings seem to support the use of brand placement in games. Players easily recall encounters with brands during game‐play and are generally positive about these experiences, suggesting that brands increase realism because it allows individuals to create and explore consumption‐based daydreams. However, some players reject brand placement, preferring in‐game fantasies that are independent of mundane commodities. The findings also raise issues related to the ways in which individuals may use digital games to reflect on our consumer society and this raises a question of the degree to which digital games may support or oppose existing consumer cultures. Other problems for managers wishing to use this technique were revealed by the repetitive nature of games which may cause message wear‐out, and by playerss' frustration with aspects of a game which may lead to negative evaluations of in‐game brands.

Copyright © 2006 John Wiley & Sons, Ltd.     

Subgames within Large Games and the Heuristic of Imitation

We study repeated normal form games where the number of players is large. We argue that it is interesting to look at such games as being divided into subgames, each of which we call a neighbourhood. The structure of such a game is given by a graph G whose nodes are players and edges denote visibility. The neighbourhoods are maximal cliques in G. The game proceeds in rounds where in each round the players of every clique X of G play a strategic form game among each other. A player at a node v strategises based on what she can observe, i.e., the strategies and the outcomes in the previous round of the players at vertices adjacent to v. Based on this, the player may switch strategies in the same neighbourhood, or migrate to another neighbourhood. We are interested in addressing questions regarding the eventual stability of such games. We incrementally impose constraints on the ‘types’ of the players. First, we look at players who are unconstrained in their strategising abilities, in that, players who may use unbounded memory. We then consider the case of memoryless players. We show that in both these cases the eventual stability of the game can be characterised in terms of potentials. We then introduce a simple modal logic in which the types of the players can be specified. We show that when the players play according to these specified types, it can be effectively decided whether the game stabilises. Finally, we look at the important heuristic of imitation. Simple imitative strategies can be specified in the logic introduced by us. We show that in a population of optimisers and imitators, we can decide how ‘worse-off’ the imitators are by playing imitative strategies rather than optimal ones.     

Collective rationality in interactive decisions: evidence for team reasoning

Decision theory and game theory rest on a fundamental assumption that players seek to maximize their individual utilities, but in some interactive decisions it seems intuitively reasonable to aim to maximize the utility of the group of players as a whole. Such team reasoning requires collective preferences and a distinctive mode of reasoning from preferences to decisions. Findings from two experiments provide evidence for collective preferences and team reasoning. In lifelike vignettes (Experiment 1) and abstract games (Experiment 2) with certain structural properties, most players preferred team-reasoning strategies to strategies supporting unique Nash equilibria, although individually rational players should choose equilibrium strategies. These findings suggest that team reasoning predicts strategy choices more powerfully than orthodox game theory in some games.     

The impact of differing audience sizes on referees and team performance from a North American perspective

The COVID-19 pandemic provides a natural experimental framework to comprehensively test the effect of crowds on both referees and players. We examine this from a North American perspective, using data from three major leagues: the National Basketball Association (NBA), National Football League (NFL) and National Hockey League (NHL). In all three leagues in the 2020–2021 season, matches were played either in empty stadiums or before diverse audience sizes. We find that the lockdown affects NBA and NFL results, by lowering the prospects of winning and the expected scoring points of the home team, when games are played without an audience. Conversely, the lockdown does not substantially influence the outcomes of NHL games. We also examine the effect of audience size on game outcomes using historical observations from the past decade, when no lockdown measures were in force. Interestingly, a larger audience size increases the chance of winning and the expected scoring points of the visiting team for NFL games. No significant effect of the audience size on match outcomes is observed for NBA or NHL games. Regarding referee decisions, spectators do not significantly influence referee calls of NHL matches. As for NBA and NFL, the lockdown significantly increases the total number of referee calls but does not prompt more biased decisions towards either of the teams. Finally, a larger audience leads to referee calls more favourable to the visiting team for NFL games. These results extend the literature regarding crowd pressure on the behaviour of players and officials, with an indication that the specific sports activity has a pivotal role in the response to a cheering audience.     

Effect of playing violent video games cooperatively or competitively on subsequent cooperative behavior

Research on video games has yielded consistent findings that violent video games increase aggression and decrease prosocial behavior. However, these studies typically examined single-player games. Of interest is the effect of cooperative play in a violent video game on subsequent cooperative or competitive behavior. Participants played Halo II (a first-person shooter game) cooperatively or competitively and then completed a modified prisoner's dilemma task to assess competitive and cooperative behavior. Compared with the competitive play conditions, players in the cooperative condition engaged in more tit-for-tat behaviors-a pattern of behavior that typically precedes cooperative behavior. The social context of game play influenced subsequent behavior more than the content of the game that was played.     

Inconsistencies in extensive games

In certain finite extensive games with perfect information, Cristina Bicchieri (1989) derives a logical contradiction from the assumptions that players are rational and that they have common knowledge of the theory of the game. She argues that this may account for play outside the Nash equilibrium. She also claims that no inconsistency arises if the players have the minimal beliefs necessary to perform backward induction. We here show that another contradiction can be derived even with minimal beliefs, so there is no paradox of common knowledge specifically. These inconsistencies do not make play outside Nash equilibrium plausible, but rather indicate that the epistemic specification must incorporate a system for belief revision. Whether rationality is common knowledge is not the issue.     

Physical Attractiveness and Altruism in Two Modified Dictator Games

Several studies find that male individuals are more altruistic toward attractive women, suggesting altruism may serve as a courtship display. Many studies exploring this phenomenon have used vignettes and facial images. We tested the sexual selection hypothesis as an explanation for altruistic behavior, where players played the dictator game with “live” participants. Two studies were conducted (Study 1, n = 212; Study 2, n = 188) where we manipulated stakes and anonymity between participants to explore the relationship between the dictator’s allocations and their perceived attractiveness of the recipient. We found no relationship between attractiveness and altruism. Dictators were consistently fair when allocating stakes, irrespective of the recipients’ attractiveness.