"We analyze the volatility surface vs. moneyness and time to expiration implied by MIBO options written on the MIB30, the most important Italian stock index. We specify and fit a number of models of the implied volatility surface and find that it has a rich and interesting structure that...

"A defining feature of business cycles is the comovement of inputs at the sectoral level with aggregate activity. Standard models cannot account for this phenomenon. This paper develops and estimates a two-sector dynamic general equilibrium model which can account for this key regularity. My...

"We analyze optimal monetary policy in an endogenous sticky price model. Similar models with exogenous sticky prices can deliver multiplicity of equilibria. Multiplicity of equilibria is a necessary condition for expectation traps to explain the variation across time and countries of inflation...