Actual individual preferences are neither complete (=total) nor antisymmetric in general, so that at least every must be an admissible input to a satisfactory choice rule. It is argued that the traditional notion of “indifference” in individual preferences is misleading and should be...

When preferences are single-peaked (Black (1948),Black et al. (1958)) or group separable Ballester and Haeringer (2011), majority voting equilibria exist. Group separability has probably not received as much attention as single-peak separability because there are no intuitive assumptions about...