This paper studies coalition formation under asymmetric information. An outside party offers private payments in order to influence the collective decision over an unpopular reform. The willingness to accept such payments is private information. The paper demonstrates that a supermajority...

This paper studies coalition formation under asymmetric information. An outside party offers private payments in order to influence the collective decision over an unpopular reform. The willingness to accept such payments is private information. The paper demonstrates that a supermajority...

This paper studies the advantages that a coalition of agents obtains by forming a voting bloc to pool their votes and cast them all together. We identify the necessary and sufficient conditions for an agent to benefit from the formation of the voting bloc, both if the agent is a member of the...

Experiments evaluate the fit of human behaviour to the Shapley-Shubik power index (SSPI), a formula of voter power. Groups of six subjects with differing votes divide a fixed purse by majority rule in online chat rooms. Earnings proxy for measured power. Chat rooms and processes for selecting...

This paper studies coalitional strategy-proofness of social choice correspondences that map preference profiles into sets of alternatives. In particular, we focus on the Pareto rule, which associates the set of Pareto optimal alternatives with each preference profile, and examine whether or not...

One feature of legislative bargaining in naturally occurring settings is that the distribution of seats or voting weights often does not accurately reflect bargaining power. Game-theoretic predictions about payoffs and coalition formation are insensitive to nominal differences in vote...

This chapter gives a flavour of recent theoretical work on coalition formation and political parties. I survey recent work on both pre-election coalition formation and post election coalition (or government) formation. A number of alternative rationales for the formation of parties are compared...

This paper studies the advantages that a coalition of agents obtains by forming a voting bloc to pool their votes and cast them all together. We identify the necessary and sufficient conditions for an agent to benefit from the formation of the voting bloc, both if the agent is a member of the...

When collective choices are made in more than one round and with different groups of decision-makers, so-called election inversions may take place, where each group have different majority outcomes. We identify two versions of such compound majority paradoxes specifically, but not exclusively,...

A stable government is by definition not dominated by any other government. However, it may happen that all governments are dominated. In graph-theoretic terms this means that the dominance graph does not possess a source. In this paper we are able to deal with this case by a clever combination...