We develop a model of common agency with complete information and general preferences with nontransferable utility, and we prove that the principals' Nash equilibrium in truthful strategies implements an efficient action. We apply this theory to the construction of a positive model of public...

This paper analyses optimal irreversible investment policy when profits are subject to a multiplicative geometric Brownian motion shock. The marginal product of capital is increasing initially and decreasing thereafter. In the latter range, optimal policy is familiar: capacity is added gradually...