Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We show by means of an example that the result of Arrow [Arrow, K.J. (1953), Le rôle des valeurs boursières pour la répartition la meilleure des risques, Econométrie, 41-47, CNRS, Paris; translated as The role of securities in the optimal allocation of risk bearing, Review of Economic Studies, 31, 91-96] is problematic when there exist multiple equilibrium continuations to the initial-period component of an intertemporal equilibrium.