Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
In this paper we consider the problem of implementation when a principal hires many agents and is not able to monitor their actions. We distinguish two cases: (i) when actions are mutually observable among agents, (ii) when actions are not observable at all. In (i), there is a mechanism in which the first-best arises as a unique perfect equilibrium. In (ii), we show by two examples that typically there are multiple equilibria if the principal merely offers a set of optimal sharing rules. However, we prove that the principal can use these optimal sharing rules as a starting point and construct a multi-stage mechanism that has a unique second-best perfect Bayesian equilibrium.