This Fall semester 2010, I'll teach two courses:
Students, please apply for these courses via the regular bidding system. Then, create an account on this homepage to download all the assignments and teaching material.
Many economic models mix continuous and discrete choices, such as a consumption/savings trade-off alongside a labor participation decision. These problems have non-differentiable and non-concave value functions. We show that the value function is differentiable at optimal choices if the underlying utility function is the upper envelope of differentiable functions. Hence, we obtain first order conditions that are necessary for optimality. We do not make any concavity assumptions.