Imagine that everyone in a group chooses a real number and then these numbers are combined to produce a group number. Suppose that when everyone moves strictly closer to some individual’s number, the group number either stays where it is or moves closer to this number. We call this the...

We characterize a rule for aggregating binary evaluations -- equivalently, dichotomous weak orders -- similar in spirit to the Borda rule from the preference aggregation literature. The binary evaluation framework was introduced as a general approach to aggregation by Wilson (J. Econ. Theory 10...

It is well known that many social decision procedures are manipulable through strategic behaviour. Typically, the decision procedures considered in the literature are social choice correspondences. In this paper we investigate the problem of constructing a social welfare function that is...

In the literature on social choice and fuzzy preferences, a central question is how to represent the transitivity of a fuzzy binary relation. Arguably the most general way of doing this is to assume a form of transitivity called max-star transitivity. The star operator in this formulation is...

We investigate the structure of fuzzy aggregation rules which, for every permissible profile of fuzzy individual preferences, specify a fuzzy social preference. We show that all fuzzy aggregation rules which are strategyproof and satisfy a minimal range condition are dictatorial. In other words,...