When people behave more cooperatively toward in-group members than to out-group members, we call it "in-group favoring behavior." However, previous studies have not yet provided a satisfactory explanation for why in-group favoritism can be adaptive. In the current study, we conducted a series of simulations to explain such behaviors from an evolutionary perspective. We used the giving game and constructed a society composed of two groups, A and B. In the game, every player was given a fixed amount of resources and decided how much and to whom he gave. The results showed that the in-group favoring strategy is adaptive only when it has a strict criterion for recipients (not giving any resources to players who had helped other players who did not adopt the in-group favoring strategy). Furthermore, they showed that there were other strategies which have a strict criterion for recipients that could be adaptive as well. These findings suggest that strategies which form a circle of exchange only among themselves by excluding other strategies can be adaptive.
The aim of this study is to identify response styles among Japanese participants. Response style research has had a methodological concern that biased responses defined by the number of counts responding to certain category options run the risk of being confounded with item contents. Thus, following the approach delineated and outlined by Billiet and McClendon (2000), this study identifies response styles with the aid of structural equation modeling. Based on the premise that stable tendencies in response behavior are related to personality traits, the impact of response styles is partialed out from item responses by modeling a "style factor." Confirmatory factor analyses on two distinctive psychological scales found a significant effect of the acquiescence response style (ARS) on item responses. On the other hand, strong evidence of the (in) extreme response style (ERS) and the mid-point response style (MRS), often mentioned as Japanese response styles, was not identified.
This study examined the effects of intergroup social justice on intergroup aggression inflicted against a wrongdoer by someone who was not directly involved in the wrongdoing (third party aggression). Specifically, it focused on whether third party aggression is retaliatory aggression or not. Sixty-four participants equally or unequally received lottery tickets from a fellow ingroup member; they then observed that the fellow ingroup member or an outgroup member unequally received such tickets from another outgroup member. After this observation, participants were given the opportunity to select the level of unpleasant noise that would be experienced by the outgroup member responsible for the unequal distribution. The results suggested that intragroup social justice enhanced group identification with the ingroup, which in turn enhanced perceived unfairness of intergroup distribution only when the victim was an ingroup member. That perceived unfairness then intensified hostility and aggressive behavior against the unfair outgroup member. Finally, the relationship between the psychological mechanisms of third party aggression and intergroup conflict in the real world was discussed.
The current study investigates the influence of social factors, such as self-interest and involvement, on trust and its determinants, in the context of public decision-making in government, through two scenario experiments. In both experiments, participants' involvement (high/low) and, subsequent interest in the high-involvement condition (agreed/opposed) were manipulated and two trust models were compared: a traditional model, which regards expectation about intention and competence as the component of trust; and an SVS model, which regards perceived salient value similarity as the primary determinant of trust. Two hypotheses were tested: 1) conflict of interest diminishes trust and value similarity; 2) expectation of the government's intention consistently predicts trust in government, regardless of self-interest. The results supported both hypotheses. Implications of value similarity in the context of public decision-making are discussed.
The effects of the motivational states of public speakers, such as rejection avoidance needs, as well as the presence or absence of an audience on psychophysiological responses when expecting to make a speech were investigated. Participants delivered a three-minute speech in a room with or without an audience. Participants completed the General Affects Scales before and after the speech, and the negative affect (NA) subscale scores of the scale were used to assess their psychological state. Salivary cortisol level was measured before and after the speech as an index of their physiological response. The results indicated that speakers with high rejection avoidance needs had greater NA prior to the speech regardless of the presence or absence of an audience. Moreover, they had increased cortisol levels only when speaking in front of an audience. Speakers with low rejection avoidance needs had greater NA when speaking in front of an audience, whereas they did not show increased cortisol levels, regardless of the presence or absence of an audience. These results suggest that when a speaker expects to deliver a speech, the speaker's motivational state and the presence or absence of an audience interactively cause changes in psychophysiological responses.
Previous studies have shown the positive effects of collective efficacy on community collective actions. As a predictor of collective efficacy, while behavioral social connectedness has shown a positive effect in some studies, the effect of cognitive social connectedness is little known. In this study, the perceived intragroup relationship (Yuki, 2003) was applied in order to investigate the relation among perceived intragroup relationship, collective efficacy, and the intention of participating in community development. We distributed questionnaires to 500 citizens and analyzed data that were collected from 121 respondents. The result of correlation analysis showed a positive relation among the intention of participating, collective efficacy, intragroup relational cognition, and behavioral social connectedness. Furthermore, a determinate process model of the intention to participate was examined using path analysis. The results indicate that perceived intragroup relationship has a positive correlation with social connectedness behavior and a positive effect on collective efficacy, but social connectedness behavior does not have a significant effect on collective efficacy.