In this chapter, we seek to review some of the central concepts and results in the literature on positionalist voting rules, which goes back to Borda (1781) . After the introduction of the basic notation and definitions in earlier parts of the chapter, we explore in Section 3 the distinction...

This paper reviews recent research on the aggregation of heterogeneous time preferences. Main results are illustrated in simple Ramsey models with two or three agents who differ in their discount factors. We employ an intertemporal view on these models and argue that preferences of a decision...

We consider the problem of ranking sets of objects, the members of which are mutually compatible. Assuming that each object is either good or bad, we axiomatically characterize three cardinality-based rules which arise naturally in this dichotomous setting. They are what we call the symmetric...

We consider the problem of allocating infinitely divisible commodities among a group of agents. Especially, we focus on the case where there are several commodities to be allocated, and agents have continuous, strictly convex, and separable preferences. In this paper, we establish that the...

We analyze bankruptcy problems with an indivisible object, where real owners and outside traders want to allocate an indivisible object among them with monetary compensation. The object might be a company that has gone bankrupt or a house left by a parent who has died, and so on. We show that...

This paper studies the possibility of secure implementation (Saijo, T., T. Sjöström, and T. Yamato (2007) "Secure Implementation," Theoretical Economics 2, pp. 203-229) in divisible and non-excludable public good economies with quasi-linear utility functions. Although Saijo, Sjöström, and...

We study strategy-proof rules for choosing between two alternatives. We consider the full preference domain which allows for indifference. In this framework, for strategy-proof rules, ontoness does not imply efficiency. We weaken the requirement of efficiency to ontoness and characterizes the...

This paper analyzes strategy-proof collective choice rules when individuals have single-crossing preferences on a finite and ordered set of social alternatives. It shows that a social choice rule is anonymous, unanimous, and strategy-proof on a maximal single-crossing domain if and only if it is...

We propose and axiomatically characterize, within Harsanyi's impartial observer setting, a utilitarian social welfare function (SWF) that can accommodate concerns for procedural fairness. Under our proposal, concerns for procedural fairness in social welfare assessments are inherited from...

This paper reviews recent research on the aggregation of heterogeneous time preferences. Main results are illustrated in simple Ramsey models with two or three agents who differ in their discount factors. We employ an intertemporal view on these models and argue that preferences of a decision...