How social preferences influence the stability of a climate coalition

This study examines the impact of social preferences on the individual incentives of participating in climate coalitions with laboratory experimental evidences. The theoretical result suggests that, when a player was inequality-neutral, a dominant strategy equilibrium could exist. However, individuals with social preference may lead a vacillated coalition formation. Joining or not joining depend on the player was critical or non-critical to an effective coalition respectively. The laboratory experimental result shows that players were inequality-averse and the coalition was usually larger than the equilibrium size but unstable. The inequality-averse attitudes have significantly positive impact on the incentives of participation. Particularly, when they are non-critical players, egalitarians are likely to give up the free riding benefit by joining a coalition. Our findings help to understand the climate coalition formation.