In-group bias in natural groups of soldiers

This study examines whether soldiers identify as soldiers rather than civilians and whether soldiers’ in-group bias is a function of their military unit (horizontal level), military rank (vertical level), or both in interaction. Our unique dataset consists of 512 German soldiers categorized by branch of service (air force, navy, and army) and status (officer candidates and officers). Based on a series of modified dictator games, our results reveal intriguing patterns. We find strong in-group bias among soldiers and robust identification as members of the military rather than civilians. Additionally, identification across branches of service is consistent and tremendously high. Furthermore, we observe an interaction between identifications across branches of service and status. Low-status groups of officer candidates exhibit significantly higher in-group bias than higher-status officers at the horizontal level (between branches of service).