Abstract: Many situational factors can affect individuals’ intention to donate money. For instance, previous studies have proved that background music and sweet smell can promote individuals’ prosocial behaviors. Individuals always experience crowded environments and under such conditions they sometimes have to response to money donation appeals. No previous research has explored the influence of individuals’ crowding perception on money donation behavior. To fill this gap, in the present study we propose and prove that individuals’ crowding perception can facilitate their money donation behavior. Individual’s physical proximity is close when exposure to crowding and so with psychological distance. Individuals feel higher self-others overlap and lower self-other distinction in crowded environments than non-crowded environments. Further those feeling induce a group level identity which threat to individual self-concept clarity. Individuals seek a balance between self-identity and collective identity. However, those crowded environments with dehumanizing characteristic blur self-identity and further activates the individuals’ need for self-expression. The larger the group, the stronger the need for self-expression. The need for self-expression activated by crowding perception makes individuals be more concerned about the moral cues and respond more positively to the monetary donation appeals. Simply put, individual response to money donation appeals positively in crowded environments as it can satisfy the need for self-expression which evoked by crowding perception. Four Studies (474 participants contained) were conducted to test the crowding perception on money donation by applying three different stimuli to manipulate crowding perception and by measuring two types of monetary donation in three contexts. Specifically, the stimuli of the donation appeal scenario and money donation measurement items in study 1 study 2A and study 2B are different. Based on study 2A, study 2B changes the scenario of donation appeal, and further shown a converging evidence that crowding perception increases the intention of money donation. Based on study 2B, study 3 changes the crowding manipulation stimuli again, and further verifies the mediation effect of need for self-expression. The results of all four studies show that the crowding perception promotes individuals’ money donation behavior. Taking the result of study 1 as an example: compared with the non-crowded condition, the participants are more willing to donate money in the crowded condition (M crowded = 5.575，SD = 1.303；M non-crowded =4.451，SD=1.362；F（1,126）= 22.736，p < .001，ηp2 = .153）. The result of study 4 reveals the mediation of need for self-expression in the influence of crowding on money donation intention (β= .3940， 95% CI = [.0835, .8700]). In conclusion, individuals’ need for self-expression is activated by the crowding (vs. non-crowding) perception. Individuals in crowded condition have a stronger need for self-expression and are driven to be more responsive to money donation appeals. They show stronger intention to donate money, and have more monthly and annual money donations. The present study enriches the antecedents research of monetary donation by exploring the effect of the perception of crowding in the environment. More importantly, the present study innovatively explores the mediation role of individual’s need for self-expression in the influence of crowding perception on money donation. It makes the most contribution and is the highlight of our present work. The research results further deepen the existing crowding research and expand the theoretical applicability of prosocial behavior in non-profit organizations.

Key words: crowding perception, money donation, need for self-expression

摘要： 通过四个实验（474名被试），采用三种不同的刺激物操纵拥挤感，在三种不同情境下测量两类金钱捐赠行为，来探索拥挤感对金钱捐赠的影响。结果发现：拥挤感强（vs. 弱）的被试有更高的金钱捐赠意愿、更高的月度和年度捐赠金额；其中个体的自我表达需要发挥中介作用，即体验到强拥挤感的个体的自我表达需要更强，为了满足这一需要，更积极响应金钱捐赠的呼吁。

关键词: 拥挤感知 金钱捐赠 自我表达需要