Three essays on strategy-proofnesschoosing intervals and locating public goods

Résumé

Voting is a very commonly used method to collect opinions in order to adopt social decisions. Usually the members of a group of individuals have different opinions about issues or different preferences over alternative courses of action, and voting procedures are intended to facilitate a satisfactory connection between social choices and individual preferences or opinions. In fact, there are many types of voting procedures and then it is useful to distinguish among them by looking at their properties, expressed in terms of axioms, that some of them may or may not satisfy. In this thesis, we study the existence of strategy-proof voting procedures in different contexts. In chapter 1, we study the existence of strategy-proof voting procedures in a context where a group of individuals must choose an interval. In chapter 2, we consider the problem of a government that has to locate two identical public facilities on a line. Finally, in chapter 3 we study the problem of locating a public bad on a line.