This paper uses a DSGE model to examine the effects of an expansion in government spending in a liquidity trap. If the liquidity trap is very prolonged, the spending multiplier can be much larger than in normal circumstances, and the budgetary costs minimal. But given this "fiscal free lunch,"...

Because policymakers may consider the state of the economy when setting taxes, endogeneity bias can arise in regression models that estimate relationships between economic variables and taxes. This paper quantifies the policy endogeneity bias and estimates the impact of R&D tax incentives on R&D...

This overview examines conditions for reliable economic policy analysis based on econometric models, focusing on the econometric concepts of exogeneity, cointegration, causality, and invariance. Weak, strong, and super exogeneity are discussed in general; and these concepts are then applied to...