We consider social choice problems where a society must choose a subset from a set of objects. Specifically, we characterize the families of strategy-proof voting procedures when not all possible subsets of objects are feasible, and voters' preferences are separable or additively representable.

This paper surveys the literature on strategy-proofness from a historical perspective. While I discuss the connections with other works on incentives in mechanism design, the main emphasis is on social choice models. This article has been prepared for the Handbook of Social Choice and Welfare,...

The rule of k names can be described as follows: given a set of candidates for office, a committee chooses k members from this set by voting, and makes a list with their names. Then a single individual from outside the committee selects one of the listed names for the office. Different variants...

Barberà and Coelho (2006) documented six screening rules associated with the rule of k names that are used by different institutions around the world. Here, we study whether these screening rules satisfy stability. A set is said to be a weak Condorcet set la Gehrlein (1985) if no candidate in...

A decision-maker exhibits preference for flexibility if he always prefers any set of alternatives to its subsets, even when two of them contain the same best element. Desire for flexibility can be explained as the consequence of the agent's uncertainty along a two-stage process, where he must...

We define different concepts of group strategy-proofness for social choice functions. We discuss the connections between the defined concepts under different assumptions on their domains of definition. We characterize the social choice functions that satisfy each one of them and whose ranges...

This paper studies economies where agents exchange indivisible goods and money. Agents have potential use for all indivisible goods and the indivisible goods are differentiated. We assume that agents have quasi-linear utilities in money, have sufficient money endowments to afford any group of...

We present a model of cooperative production in which rational agents might carry out sabotage activities that decrease output. We provide necessary and sufficient conditions for the existence of a Nash equilibrium without sabotage. It is shown that the absence of sabotage in equilibrium depends...

This paper studies economies where agents exchange indivisible goods and money. Agents have potential use for all indivisible goods and the indivisible goods are differentiated. We assume that agents have quasi-linear utilities in money, have sufficient money endowments to afford any group of...

We provide an elementary proof showing how in economics with an arbitrary number of agents an arbitrary number of public goods and utility functions quasi-linear in money, any efficient and individually rational mechanism is not strategy-proof for any economy satisfying a mild regularity...