We compare methods to solve for optimal policies in heterogeneous agent-models with and without aggregate shocks, considering the optimal provision of a public good in a heterogeneous-agent economy. We first use a method based on transitions that we modify to neutralize the effect of the initial...

We set up a model where asset price bubbles due to risk shifting can be moderated by capital requirements. However, imperfect information about the ratio of required capital, or, in the context of the sub-prime crisis, the extent of regulatory arbitrage, introduces uncertainty about the risk...