The practical relevance of favouritism among students of the same study path is evident in lifelong memberships in fraternities or sororities or in high donations to faculties. In our study, we focus on the in-group favouritism of students by examining the trade-off of acting based on in-group...

Alliances often provide a collective good among their allies. This article offers laboratory experimental evidence that the possibility to vote for the exclusion of non-cooperating allies, i.e. ostracism, can be a powerful negative referendum to increase allies’ contributions to the collective...