Strategy-proof social choice

The Structure of Strategy-Proof Social Choice Part II: Non-Dictatorship, Anonymity and Neutrality*

Domains of generalized single-peaked preferences are classified in terms of the extent to which they enable well-behaved strategy-proof social choice. Generalizing the Gibbard-Satterthwaite Theorem, we characterize the domains that admit non-dictatorial strategy-proof social choice functions. We also provide characterizations of the domains that enable locally non-dictatorial, anonymous, and ne...

On domains that admit well-behaved strategy-proof social choice functions

In this paper, we investigate domains which admit “well-behaved”, strategy-proof social choice functions. We show that if the number of voters is even, then every domain that satisfies a richness condition and admits an anonymous, tops-only, unanimous and strategy-proof social choice function, must be semi-single-peaked. Conversely every semi-single-peaked domain admits an anonymous, tops-only,...

Characterization of Domains Admitting Strategy-Proof and Non-Dictatorial Social Choice Functions with Infinite Sets of Alternatives

We show, with an example, that the theorem on the characterization of the domains admitting strategy-proof and non-dictatorial social choice functions by Kalai and Muller (1977) does not hold when the set of alternatives is infinite. We consider two ways of overcoming this problem. The first identifies a set of domains admitting strategy-proof and non-dictatorial social choice functions when th...

An introduction to strategy-proof social choice functions

Strategy-Proofness and the Tops-Only Property

A social choice function satisfies the tops-only property if the chosen alternative only depends on each person’s report of his most-preferred alternatives on the range of this function. On many domains, strategyproofness implies the tops-only property, provided that the range of the social choice function satisfies some regularity condition. The existing proofs of this result are model specifi...

On strategy-proof social choice under categorization

In this paper, I consider the social choice problems such that (i) the set of alternatives can be categorized into two groups based on some prominent and objective feature and (ii) the agents have strict preferences over the candidates. I introduce a notion of linear dichotomous domains to describe a class of plausible preference profiles in these social choice problems. My main result is a cha...