In or out? The paradox of exclusionary mechanisms in keeping cooperation going

The question of who's in and who's out is not as straightforward as it seems when understanding the dynamics of exclusion in everyday life. This dissertation explores the intricate dynamics of cooperation and exclusionary mechanisms in social networks and groups by combining insights from formal theoretical modeling and empirical analysis, incorporating perspectives from multiple disciplines. From the stability of social value orientations over time to the contextual influence on cooperation dynamics, this dissertation provides novel and nuanced views on the ways in which exclusion encourages cooperative behavior among individuals and – more importantly- when exclusion fails to promote cooperation. The research findings pave the way for future research in the field of exclusion, both theoretically and empirically, and highlight a downside for excluded defectors: If there is no “in” after exclusion, they may fall into a spiral of defection with a difficult road ahead for (if ever) reaching cooperation “at the end of the tunnel.”