Several recent papers have proposed recursive Lagrangian-basedmethods for solving dynamic contracting problems. Thesemethods give rise to Bellman operators that incorporate either a dual inf-sup or a saddle point operation. We give conditions that ensure the Bellman operator implied by a dual recursive formulation is contractive. JEL codes: C61, C73, D82, E61.

We consider the static and dynamic models of Cournot duopoly with tax evasion. In the dynamic model we introduce the time delay and we analyze the local stability of the stationary state. There is a critical value of the delay when the Hopf bifurcation occurs. Mathematics Subject Classification: 34K18, 47N10; Jel Classification: C61, C62, H26

We provide necessary optimality conditions for a general class of discounted infinitehorizon dynamic optimization problems. As part of the resulting maximum principle we obtain explicit bounds on the adjoint variable, stronger than the transversality conditions in Arrow–Kurz form. r 2005 Elsevier B.V. All rights reserved. JEL classification: C60; C61

This paper develops a theory of regular Markov perfect equilibria in dynamic stochastic games. We show that almost all dynamic stochastic games have a finite number of locally isolated Markov perfect equilibria that are all regular. These equilibria are essential and strongly stable. Moreover, they all admit purification. JEL classification numbers: C73, C61, C62.

In this paper we deal with the utility maximization problem with a general utility function. We derive a new approach in which we reduce the utility maximization problem with general utility to the study of a fully-coupled Forward-Backward Stochastic Differential Equation (FBSDE). AMS Subject Classification: Primary 60H10, 93E20 JEL Classification: C61, D52, D53

The paper proposes an Euler equation technique for analyzing the stability of differentiable stochastic programs. The main innovation is to use marginal reward directly as a Foster–Lyapunov function. This allows us to extend known stability results for stochastic optimal growth models, both weakening hypotheses and strengthening conclusions. JEL classification: C61; C62; O41