Expectations matter for economic activity. To the extent that they are fundamentally unwarranted, they represent "undue optimism or pessimism" (Pigou, 1927). In this paper, we identify empirically the effect of undue optimism/pessism ("optimism shocks") on economic activity. In a first step, we...

We provide a nonlinear characterization of the macroeconomic impact of microeconomic productivity shocks in terms of reduced-form non-parametric elasticities for efficient economies. We also show how microeconomic parameters are mapped to these reduced-form general equilibrium elasticities. In...

This paper explores the importance of investment-specific technology changes in anticipated TFP fluctuations. To this end, we identify two types of news shocks with the maximum forecast error variance approach: news shocks to TFP and news shocks to the relative price of investment. We show in a...