This paper studies the effects on electoral competition of political parties relying on monetary donations and volunteer labour for their electioneering activities. It also examines whether a recorded decline in party activism increases special-interest influence on party policy platforms....

Previous research shows that collective action to avoid a catastrophic threshold, such as a climate “tipping point,” is unaffected by uncertainty about the impact of crossing the threshold but that collective action collapses if the location of the threshold is uncertain. Theory suggests...

We investigate situations in which players make costly contributions as group members in a group conflict, and at the same time engage in contest with fellow group members to appropriate the possible reward. We introduce within group power asymmetry and complementarity in members’ efforts, and...