The game of political entry with truly effective identical players

This paper presents a general formal model for analyzing political entry decisions in strategic contexts. The model focuses on dichotomous entry decisions made by potential entrants in a full information setting. The players in the proposed entry game are truly effective equals. That is, they share common payoffs (their preferences are identical) and an individual's entry decision always affects his and the other players' payoffs. We illustrate the relevance and applicability of the model to the study of diverse issues such as voluntary contribution to the provision of public goods (e.g. private charitable contributions or individual participation in organizational decision-making) and the formation of exclusive and non-exclusive benefit groups (e.g. clubs, political parties, labor unions). Within the above-mentioned particular contexts two issues are of paramount significance. First, the characterization of the equilibrium and efficient entry (participation) levels. Second, the comparison between these levels. Both issues are briefly analyzed. It is shown that the equilibrium number of entrants can be efficient or inefficient depending on the specific form of the players' payoff functions. In particular, depending on the degree of excludability of non-entrants from the benefits accruing to entrants, on the degree of subtractability of the benefits, on whether the benefits are increasing or decreasing with the number of entrants and on the costs of entry.