著者

三船 恒裕 横田 晋大

出版者

日本社会心理学会

雑誌

社会心理学研究 (ISSN:09161503)

巻号頁・発行日

vol.34, no.2, pp.94-101, 2018-11-30 (Released:2018-12-15)

参考文献数

28

被引用文献数

5

---

The relationships between social dominance orientation (SDO) and political attitudes and prejudice have been investigated mainly in Western societies, with little known about them in other societies, especially in Japan. In this study, we examined the external validity of the SDO scale and the relationship between SDO and discriminatory attitudes toward foreigners using samples of Japanese undergraduates and adults from the general population. Across four studies, the results confirmed the reliability of the Japanese SDO scale and found that SDO positively correlated with political conservatism, such as taking a firm stance on the “Takeshima” Island (“Dokdo” in Korean) or “Senkaku” Islands (“Diaoyu Islands” in Chinese and “Diaoyutai Islands” in Taiwanese) problems, negative and avoidant attitudes towards foreigners, and discriminatory attitudes toward Korean residents in Japan. We also found that some gender differences of political attitudes and prejudice were statistically mediated by the gender difference of SDO. These results suggest that SDO can be one of valid explanations to understand the individual differences in Japanese political and discriminatory attitudes.

著者

横田 晋大

出版者

心理学評論刊行会

雑誌

心理学評論 (ISSN:03861058)

巻号頁・発行日

vol.60, no.1, pp.15-22, 2017 (Released:2018-07-20)

参考文献数

78

被引用文献数

2

---

In this paper, the evolutionary roots of gender differences in aggressive behavior are presented. Previous studies in the field of social psychology have shown that men are more aggressive than women not only in interpersonal, but also in intergroup relationships. From an evolutionary psychological view, it is predicted that outgroup aggression is triggered by the psychological mechanisms adapted to intergroup conflict specified for males. However, social psychologists demonstrated that ingroup cooperation, but not outgroup aggression, was dominant in intergroup conflict situations in a laboratory experiment. On the other hand, in these days, some evidence in the field of cultural anthropology, ethnography, and bioarcheology have clearly shown that hunter-gatherer and forager males frequently engaged in war. I discuss whether intergroup conflict influences selection pressure on male aggressive behavior as a reproductive strategy to enhance fitness.

著者

佐倉 統 平石 界 池田 功毅 中西 大輔 横田 晋大 三浦 麻子 小森 政嗣 松村 真宏 林 香里 武田 徹 水島 希

出版者

東京大学

雑誌

基盤研究(A)

巻号頁・発行日

2013-10-21

---

放射線リスクの認知特性と社会内拡散動態を明らかにし、風評被害や差別の抑制に貢献することが目的である。個人の認知的特性を対象とする行動免疫班の実験は、放射線リスクに対する忌避感情が当初の予想より強固で制御困難であることを明らかにした。放射線リスク関連情報のツイッターでの動態を解明するソーシャルメディア班は、放射線についての否定的感情が強力であり、他の災害リスクと異なる拡散パターンを確認した。抑圧的でないリスク管理の方途を考察する社会実装班は、感染症などの過去の風評被害や差別の事例との比較分析やメディア論的考察をおこなった。研究遂行および成果発表は福島の研究者や生活者と共有することを心がけた。

著者

横田 晋大 中西 大輔

出版者

日本社会心理学会

雑誌

社会心理学研究 (ISSN:09161503)

巻号頁・発行日

vol.27, no.2, pp.75-82, 2012

---

Previous research has shown that ingroup cooperation tends to flourish in intergroup conflict situations. However, the free-rider problem remains unsolved, even in intergroup conflict situations. In this study, based on multi-group selection theory and cultural-group selection theory, we hypothesized that conformity (frequency-dependent behavior) may contribute to enhancing ingroup cooperation. The results of an evolutionary simulation revealed that ingroup cooperation and conformity can evolve in situations of intergroup conflict. When such conflict is mild, agents who cooperate with ingroup members and adjust their behavior to ingroup cooperation rates facilitate cooperation in their own group. However, no effect of conformity on ingroup cooperation was observed during intense intergroup conflict, even though conformity continued to evolve. We discuss the implications of these results and suggest avenues for future research.

著者

中川 裕美 横田 晋大 中西 大輔

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

pp.90.17335, (Released:2018-12-25)

参考文献数

27

被引用文献数

1

---

This study aimed to test the validity of social identity theory (SIT) and bounded generalized reciprocity hypothesis (BGR) to explain ingroup cooperation in real social groups. Each of the validity of SIT and BGR have been discussed by social psychologists for a long time. However, recent studies indicate that both theories could explain ingroup cooperation simultaneously. Nakagawa et al. (2015) showed that ingroup cooperation among Japanese fans of a baseball team was derived from the psychological mechanisms predicted by both theories. The present study tested the reproducibility of these results when the cost of cooperation was emphasized. Japanese fans of all 12 baseball teams (N = 1,635) participated in this experiment. In each scenario, the cost of helping was emphasized, and reciprocal expectation was manipulated by knowledge about the feeling of belonging by participants and their partner’s group. The results showed that ingroup cooperation was shown by the psychological mechanism of BGR more than SIT when the cost of cooperation was emphasized.

著者

中川 裕美 横田 晋大 中西 大輔

出版者

日本社会心理学会

雑誌

社会心理学研究 (ISSN:09161503)

巻号頁・発行日

vol.30, no.3, pp.153-163, 2015-03-20 (Released:2015-06-07)

参考文献数

48

被引用文献数

4

---

In this study, we tested the theoretical validity of both Social Identity Theory (SIT) and the Bounded Generalized Reciprocity Hypothesis (BGR) for explaining in-group cooperation in real social groups. While most previous investigation on real social groups has found support for SIT, confirmatory evidence for BGR remains limited. We conducted a vignette experiment in which reciprocity was manipulated by controlling knowledge of group membership. The participants were 117 undergraduate students who were baseball fans. To control expectation of reciprocity in the experiment, we asked participants to imagine scenarios where they helped others who wore either the same baseball team T-shirts as they did or plain T-shirts. Consistent with BGR, participants tend to cooperate with in-group members when both they and their partner knew that they might be supporters of the same team. On the other hand, participants showed in-group cooperation even when only they knew their partner’s group membership. This finding coincided with SIT. These results thus further verified the theoretical validity of both SIT and BGR in real social groups.

著者

藤川 真子 横田 晋大 徳岡 大 中西 大輔

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

pp.94.22334, (Released:2023-10-31)

参考文献数

19

---

We replicated the experiment reported by Eriksson and Coultas (2009) to examine conformity bias. Conformity bias refers to the imitation behavior that most group members adopt with the probability exceeding the ratio of employment by the members in deciding their behavior. Previous studies have examined whether conformity bias can be observed in an information-seeking situation with high uncertainty. Eriksson and Coultas (2009) found no conformity bias using quizzes in which the answers were not objectively fixed as correct or incorrect (e.g., belief, preference, and norm). We replicated their experiment using questions with fixed answers. In this study (N = 120), after participants answered “yes/no” to 14 questions, they were informed of the four patterns of the distribution of the other nine participants’ responses (9, 6, 3, 0 participants said “yes”). Then, participants completed the same questions again. The results showed that conformity bias was observed. We discuss the inconsistency of the results between the previous study and our study.

著者

中西 大輔 横田 晋大

出版者

日本社会心理学会

雑誌

社会心理学研究 (ISSN:09161503)

巻号頁・発行日

vol.31, no.3, pp.193-199, 2016-03-18 (Released:2016-03-28)

参考文献数

23

---

Using evolutionary simulation, Yokota and Nakanishi (2012) have shown that majority syncing (generalized tit-for-tat strategy) is an adaptive strategy in intergroup conflict situations. When intergroup conflict is mild, agents who cooperate with ingroup members and ensure their behavior conforms to other members’ cooperation rates facilitate cooperation in their own group. This finding is supported by multi-group selection theory and by cultural group selection theory. However, this model addresses only majority-syncing as a social influence strategy. The current study introduced a minority-syncing strategy to Yokota and Nakanishi’s (2012) model. There were four conditions: Majority-syncing (agents conformed to the majority, but not to the minority), no conformity (agents did not conform), minority-syncing (agents conformed to the minority, but not to the majority), and mixed (both majority- and minority-syncing strategies were used). Computer simulation revealed that the cooperation rate decreased when minority-syncing was introduced. The cooperation rate of the no-conformity condition was higher than of both the minority and the mixed conditions. We discuss the implications of minority-syncing.

著者

横田 晋大 結城 雅樹

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

vol.80, no.3, pp.246-251, 2009 (Released:2012-03-14)

参考文献数

28

被引用文献数

5 2

---

Recent research has suggested that two distinct psychological processes lead to ingroup favoritism in the minimal group paradigm (MGP) : the motivation to gain positive intergroup distinctiveness, and the motivation to maintain intragroup cooperation. In this study, we tested a hypothesis based on the adaptationist perspective, that different situational cues suggesting intergroup threat or intragroup interdependence would elicit ingroup favoritism via these distinct psychological processes. Ninety-one Japanese undergraduates participated in a minimal group experiment and performed a reward allocation task. The results supported our predictions. Participants did not show ingroup favoritism in the control condition, where only pure ingroup-outgroup categorization was made. However, they showed ingroup favoritism when they were exposed to intergroup threat in an ostensibly unrelated task prior to reward allocation (intergroup threat condition). Moreover, a positive correlation between ingroup favoritism and the motivation to maximize positive intergroup distinctiveness was observed only in the intergroup threat condition. Likewise, participants showed ingroup favoritism in the interdependence condition, where they were presented with cues suggesting interdependence within the ingroup. The significance and implications of the findings are discussed.

著者

横田 晋大 中西 大輔

出版者

広島修道大学

雑誌

広島修大論集 (ISSN:18831400)

巻号頁・発行日

vol.51, no.2, pp.23-36, 2011-02-28

著者

中川 裕美 横田 晋大 中西 大輔

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

pp.93.21316, (Released:2022-08-30)

参考文献数

29

---

The present study investigated the replicability of a series of Nakagawa et al.’s research. The findings in the previous studies showed ingroup cooperation based on the Social Identity Theory (SIT) and the Bounded Generalized Reciprocity hypothesis (BGR). The cost of cooperation can moderate the relationship between ingroup collaboration and the expectation of reciprocity. However, none of the studies explicitly addressed outgroup members. Consequently, these studies are limited in SIT validity. Research should investigate whether people become more cooperative within an ingroup versus an outgroup. Therefore, we measured ingroup cooperation using the vignette study of Nakagawa et al. (2015). We added an outgroup member version to maintain the salience of the intergroup situation. Our results reproduce Nakagawa et al.’s research and show that cooperation within an ingroup is more significant than that with an outgroup, based on the generated psychological mechanisms of both theories.

著者

横田 晋大 中西 大輔 ヨコタ クニヒロ ナカニシ ダイスケ Kunihiro Yokota Daisuke Nakanishi

出版者

広島修道大学学術交流センター

雑誌

広島修大論集

巻号頁・発行日

vol.51, no.2, pp.23-36, 2011-02-28

著者

中川 裕美 横田 晋大 中西 大輔

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

vol.90, no.1, pp.87-92, 2019 (Released:2019-04-25)

参考文献数

27

被引用文献数

1

---

This study aimed to test the validity of social identity theory (SIT) and bounded generalized reciprocity hypothesis (BGR) to explain ingroup cooperation in real social groups. Each of the validity of SIT and BGR have been discussed by social psychologists for a long time. However, recent studies indicate that both theories could explain ingroup cooperation simultaneously. Nakagawa et al. (2015) showed that ingroup cooperation among Japanese fans of a baseball team was derived from the psychological mechanisms predicted by both theories. The present study tested the reproducibility of these results when the cost of cooperation was emphasized. Japanese fans of all 12 baseball teams (N = 1,635) participated in this experiment. In each scenario, the cost of helping was emphasized, and reciprocal expectation was manipulated by knowledge about the feeling of belonging by participants and their partner’s group. The results showed that ingroup cooperation was shown by the psychological mechanism of BGR more than SIT when the cost of cooperation was emphasized.

著者

品田 瑞穂 山岸 俊男 谷田 林士 高橋 知里 犬飼 佳吾 小泉 径子 横田 晋大 三船 恒裕 高岸 治人 堀田 結孝 橋本 博文

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

vol.81, no.2, pp.149-157, 2010 (Released:2010-09-09)

参考文献数

31

被引用文献数

1 1

---

Cooperation in interdependent relationships is based on reciprocity in repeated interactions. However, cooperation in one-shot relationships cannot be explained by reciprocity. Frank, Gilovich, & Regan (1993) argued that cooperative behavior in one-shot interactions can be adaptive if cooperators displayed particular signals and people were able to distinguish cooperators from non-cooperators by decoding these signals. We argue that attractiveness and facial expressiveness are signals of cooperators. We conducted an experiment to examine if these signals influence the detection accuracy of cooperative behavior. Our participants (blind to the target's behavior in a Trust Game) viewed 30-seconds video-clips. Each video-clip was comprised of a cooperator and a non-cooperator in a Trust Game. The participants judged which one of the pair gave more money to the other participant. We found that participants were able to detect cooperators with a higher accuracy than chance. Furthermore, participants rated male non-cooperators as more attractive than male cooperators, and rated cooperators more expressive than non-cooperators. Further analyses showed that attractiveness inhibited detection accuracy while facial expressiveness fostered it.

著者

横田 晋大 中西 大輔

出版者

日本社会心理学会

雑誌

社会心理学研究 (ISSN:09161503)

巻号頁・発行日

vol.27, no.2, pp.75-82, 2012-01-31 (Released:2017-02-22)

---

Previous research has shown that ingroup cooperation tends to flourish in intergroup conflict situations. However, the free-rider problem remains unsolved, even in intergroup conflict situations. In this study, based on multi-group selection theory and cultural-group selection theory, we hypothesized that conformity (frequency-dependent behavior) may contribute to enhancing ingroup cooperation. The results of an evolutionary simulation revealed that ingroup cooperation and conformity can evolve in situations of intergroup conflict. When such conflict is mild, agents who cooperate with ingroup members and adjust their behavior to ingroup cooperation rates facilitate cooperation in their own group. However, no effect of conformity on ingroup cooperation was observed during intense intergroup conflict, even though conformity continued to evolve. We discuss the implications of these results and suggest avenues for future research.

著者

横田 晋大 結城 雅樹

出版者

北海道心理学会

雑誌

北海道心理学研究 (ISSN:09182756)

巻号頁・発行日

vol.33, pp.11-26, 2010-03-31

---

近年,適応論に基づく研究において,人が様々な種類の外集団からの脅威に対抗するために,脅威の種類に応じた多様な心理メカニズムと行動傾向を持つ可能性に注目が集まっている。本研究では,外集団脅威への適応心理メカニズムの性差を検討した。男性には,外集団からの資源の強奪や暴力 (“妨害脅威”) に対抗するための心理メカニズムが,女性には,外集団から未知の病原体の感染 (“感染脅威”) に対抗するための心理メカニズムが備わっているという仮説を立て,実験室実験にて検証した。大学生166名が参加し,事前に外集団脅威の状況手がかりの有無と種類(妨害vs. 感染)を操作した後,最小条件集団状況で報酬分配課題を行った。その結果,予測通り,妨害脅威条件では男性でのみ,感染脅威条件では女性のみで差別行動が見られた。しかし,予測と異なり,脅威の手がかりが存在しない統制条件においても,男性の差別行動が見られた。

著者

横田 晋大 三船 恒裕 杉浦 仁美

出版者

広島修道大学

雑誌

基盤研究(C)

巻号頁・発行日

2018-04-01

---

2019年度では、場面想定法を用いた質問紙実験を2度実施した。まず、申請内容にもある、外集団攻撃を行う人物への魅力度評価を行った(2019年7月)。結果は、男性戦士仮説を支持するものではなく、協力的な人物への評価が高いことが示されるのみであった。この結果を受け、本研究の仮説と方法を修正した。男性戦士仮説で述べられている、集団間葛藤により男性の繁殖成功度の向上は、内集団成員からもたらされるというよりもむしろ、外集団から資源を奪うことにある。そのため、質問紙実験において、集団間状況で外集団攻撃の生起を測定するIPD-MDにおいて、各集団の性比の教示を操作し、外集団攻撃が生起するか否かを検討した(2020年1月)。その結果、男性は、男性のみの集団間関係において外集団攻撃の傾向が見られた。しかし、外集団に異性が一人含まれているという教示は外集団攻撃に影響は与えていなかった。以上の結果は、2020年度の日本社会心理学会および日本人間進化行動学会にて発表予定である。

著者

平石 界 池田 功毅 中西 大輔 横田 晋大

出版者

慶應義塾大学

雑誌

基盤研究(B)

巻号頁・発行日

2016-04-01

---

2017年度は、「評価的条件付けによる風評被害の導出」実験、「確率見積りバイアスの検討」実験を進めつつ、本研究プロジェクトの基盤となった前プロジェクトによって収集したWeb調査データに継続させる形で本プロジェクトで収集したWeb調査データを合わせた分析を行った。「評価的条件付けによる風評被害の導出」実験については、分担研究者の池田(学振/中京大学)のもと、ネガティブな評価条件づけと脳波測定を組み合わせた実験のセッティングを進めた。「確率見積りバイアスの検討」実験について、前年度に作成した実験プログラムを用いて、クラウドソーシングを用いて一般サンプルからのデータ収集の予備実験を行った。大学生を対象とした実験室実験の場合と異なり、クラウドソーシングならではの問題点が浮かび上がる一方、より優れた実験デザインでの実施が可能となることが示されたため、実験プログラムのアップデートを進めた。2013年度より継続して、福島第一原発事故に関連して、放射能リスク認知にかんするWeb調査を行ってきた。2014年3月以来、2017年2月まで。放射能を含む様々な種類のリスク認知にかんして、同一サンプルからの、福島第一原発事故の3年後、4年後、6年後の継続データを取得してきたが、6年を経てもなお放射能へのリスク認知にほとんど変化は生じていないことが示された(池田・平石・中西・横田, 2017)。この知見の頑健さを確認するために、異なるサンプルに対して同一項目のWeb調査を2018年3月に実施した。一方、放射能リスク認知への科学リテラシーの影響については、3度のWeb調査を経て、一貫してリテラシーの高さが偏ったリスク認知を低減させないという結果が得られている(中西・横田・井川, 2017)。本知見については論文を投稿中である。

著者

三船 恒裕 横田 晋大

出版者

日本社会心理学会

雑誌

社会心理学研究 = Japanese journal of social psychology (ISSN:09161503)

巻号頁・発行日

vol.34, no.2, pp.94-101, 2018-11

著者

中川 裕美 横田 晋大 中西 大輔

出版者

The Japanese Society of Social Psychology

雑誌

社会心理学研究 (ISSN:09161503)

巻号頁・発行日

vol.30, no.3, pp.153-163, 2015

---

In this study, we tested the theoretical validity of both Social Identity Theory (SIT) and the Bounded Generalized Reciprocity Hypothesis (BGR) for explaining in-group cooperation in real social groups. While most previous investigation on real social groups has found support for SIT, confirmatory evidence for BGR remains limited. We conducted a vignette experiment in which reciprocity was manipulated by controlling knowledge of group membership. The participants were 117 undergraduate students who were baseball fans. To control expectation of reciprocity in the experiment, we asked participants to imagine scenarios where they helped others who wore either the same baseball team T-shirts as they did or plain T-shirts. Consistent with BGR, participants tend to cooperate with in-group members when both they and their partner knew that they might be supporters of the same team. On the other hand, participants showed in-group cooperation even when only they knew their partner's group membership. This finding coincided with SIT. These results thus further verified the theoretical validity of both SIT and BGR in real social groups.