Non-exclusive group contests: An experimental analysis

We experimentally study a non-exclusive group contest in which contestants actively participate in multiple groups simultaneously. We compare the results of this contest to those of an exclusive group contest in which each contestant belongs to a single group. In contrast to theoretical predictions, we find that the non-exclusive group contest generates less aggregate effort than the equivalent exclusive group contest. We hypothesize that groups in the non-exclusive group contest are less responsive to their rival group’s effort than those in the exclusive group contest. Likewise, on the individual level, players in the non-exclusive group contest are more likely to free-ride on their group members’ contributions. Our data indicate that non-free-riders in the non-exclusive group contest are more likely, over time, to allocate their effort toward a single group. This finding is consistent with previous findings that players facing a complex strategy space tend to focus on specific winning combinations. Moreover, given that players are affected by their group members’ contributions, they tend to exert their effort primarily toward a single group. Taken together, our findings suggest that a non-exclusive group contest may evolve, over time, into an exclusive group contest.