Does competition affect moral behavior? This fundamental question has been debated among leading scholars for centuries, and more recently, it has been tested in experimental studies yielding a body of rather inconclusive empirical evidence. A potential source of ambivalent empirical results on the same hypothesis is design heterogeneity—variation in true effect sizes across various reasonable experimental research protocols. To provide further evidence on whether competition affects moral behavior and to examine whether the generalizability of a single experimental study is jeopardized by design heterogeneity, we invited independent research teams to contribute experimental designs to a crowd-sourced project. In a large-scale online data collection, 18,123 experimental participants were randomly allocated to 45 randomly selected experimental designs out of 95 submitted designs. We find a small adverse effect of competition on moral behavior in a meta-analysis of the pooled data. The crowd-sourced design of our study allows for a clean identification and estimation of the variation in effect sizes above and beyond what could be expected due to sampling variance. We find substantial design heterogeneity—estimated to be about 1.6 times as large as the average standard error of effect size estimates of the 45 research designs—indicating that the informativeness and generalizability of results based on a single experimental design are limited. Drawing strong conclusions about the underlying hypotheses in the presence of substantive design heterogeneity requires moving toward much larger data collections on various experimental designs testing the same hypothesis.

In this study, we investigate whether and to what extent community managers in online collaborative communities can stimulate community activities through their engagement. Using a novel data set of 22 large online idea crowdsourcing campaigns, we find that moderate but steady manager activities are adequate to enhance community participation. Moreover, we show that appreciation, motivation, and intellectual stimulation by community managers are positively associated with community participation but that the effectiveness of these communication strategies depends on the form of participation managers wish to encourage. Finally, the data reveal that community manager activities requiring more effort, such as media file uploads vs. simple written comments, have a stronger effect on community participation.

Using administrative data for West Germany, this paper investigates whether part of the urban wage premium stems from greater competition in denser labor markets. We show that employers possess less wage-setting power in denser markets. We further document that an important part of the observed urban wage premia can be explained by greater competition in denser labor markets.

The mission of a job affects the type of worker attracted to an organization but may also provide incentives to an existing workforce. We conducted a natural field experiment with 246 short-term workers. We randomly allocated some of these workers to either a prosocial or a commercial job. Our data suggest that the mission of a job has a performance-enhancing motivational impact on particular individuals only, those with a prosocial attitude. However, the mission is very important if it has been actively selected. Those workers who have chosen to contribute to a social cause outperform the ones randomly assigned to the same job by about half a standard deviation. This effect seems to be a universal phenomenon that is not driven by information about the alternative job, the choice itself, or a particular subgroup.

Refugee integration requires broad support from the host society, but only a minority is actively engaged. Given that most individuals reciprocate kind behavior, we examine the idea that the proportion of supporters will increase as a reciprocal response to refugees’ contributions to society through volunteering. Our nationwide survey experiment shows that citizens’ intentions to contribute time and money rise significantly when they learn about refugees’ pro-social activities. However, we find a substantial heterogeneity in the observed treatment effects. Individuals with a high reciprocal inclination show higher willingness to contribute time, while individuals with a lower reciprocal inclination are ready to contribute money after learning about the refugees' good deeds. Information regarding the possibility to establish a mutual support relationship with the refugees does not generally increase the willingness to contribute time or money beyond the information on refugees’ general contributions to the society. We complement this investigation with experiments in the lab and the field that confirm our findings for actual behavior.