A technical note on finite best-worst random utility model representations

This paper investigates the random utility representation of best-worst choice probabilities (picking the best and the worst alternative from an offered set). Doignon (2023) presented a complete characterization of the best-worst-choice polytope on four alternatives. Moreover, using polytope methods he showed that the Block-Marschak inequalities for best-worst choices are not sufficient for a random utility representation of best-worst choices for sets of four or more alternatives. Following the approach of Falmagne (1978), we present novel necessary and sufficient conditions for the construction of a probability measure on the set of rankings for a set of four alternatives implying a random utility representation.