Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We study the problem of aggregating expert judgments to decide the winner of a competition. Experts can be biased and then their preferences are not necessarily aligned with their judgments. Society’s optimal choice relies only on the experts’ judgments. A social choice rule (SCR) is sub-majoritarian with quota q≤n2 (being n the number of experts) if, whenever there is at least one candidate that at least q of the experts think is best, the SCR selects one of these candidates. Because the experts’ judgments are not contractual, the social planner has to design a mechanism that implements the SCR. We determine a necessary condition of impartiality on the group of experts for a sub-majoritarian SCR with quota q≥2 to be implementable in an ordinal equilibrium concept.