Consumption externality is introduced into the Ramsey equilibrium model. Existence of Ramsey equilibrium is demonstrated.

In this paper, the model of endogenous fertility proposed by Becker and Barro (1988), and extended by Benhabib and Nishimura (1989) is considered. However, in their model, the uniqueness of the optimal path may fail to hold. Furthermore, the value function may not be concave, because of the...