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, strategy-proofness implies the tops-only property provided that the range of the social...

Many decisions regarding the choice of public policies affect the size and composition of the population. In order to choose rationally in those situations, therefore, normative criteria must be capable of comparing states of affairs with different populations. This paper introduces a new class...