This paper studies the interaction of agents' collateral price beliefs, credit constraint and aggregate economic activity over the business cycle. Learning strengthens the role of collateral constraints in aggregate fluctuations. Under Heterogeneous learning rules, numerical simulations...

This comment shows that the "optimality" conditions in Assenza and Berardi (2009, JEDC) "Learning in a Credit Economy" imply that agents' "optimal" choices are either suboptimal or infeasible. It presents the correct optimality conditions and discusses the effect on the E-stability condition of...