Alliances and negotiations: an incomplete information example

We study a bargaining game between an individual and an 'alliance' in the sense of Manzini and Mariotti (J Econ Theory 121: 128-41, 2005), in which the opponent of the alliance is incompletely informed about the relative strengths of its members. The best equilibrium outcome for the alliance under a unanimity rule is not attainable with a non-unanimity rule. However, unlike in the complete information model, less than optimal outcomes and delays may occur with positive probability even under unanimity, depending on the prior beliefs and the preferences of the agents.