At the zero lower bound, the central bank's inability to offset shocks endogenously generates volatility. In this setting, an increase in uncertainty about future shocks causes significant contractions in the economy and may lead to non-existence of an equilibrium. The form of the monetary...

Can increased uncertainty about the future cause a contraction in output and its components? An identified uncertainty shock in the data causes significant declines in output, consumption, investment, and hours worked. Standard general-equilibrium models with flexible prices cannot reproduce...