Title: Uncertainty and the dynamics of r&d
Description: "Uncertainty varies strongly over time, rising by 50% to 100% in recessions and by up to 200% after major economic and political shocks.  This paper shows that higher uncertainty reduces the responsiveness of R&D to changes in business conditions - a "caution-effect" - making it more persistent over time.  Thus, uncertainty will play a critical role in shaping the dynamics of R&D through the business cycle, and its response to technology policy.  I also show that if firms are increasing their level of R&D then the effect of uncertainty will be negative, while if firms are reducing R&D then the effect of uncertainty will be positive"--National Bureau of Economic Research web site.