Technology news and the U.S. economy: Time variation and structural changes

This paper examines the time varying impact of technology news shocks on the U.S. economy during the Post-World War II era using a structural time varying parameter vector autoregressive (TVP-VAR) model. The identification restrictions are derived froma standard new Keynesian dynamic stochastic general equilibrium (DSGE) model and hold for a wide range of parameter constellations. In addition, the set of restrictions is sufficient to discriminate technology news shocks from other supply and demand side disturbances - technology surprise shocks among them. Overall, there is little evidence that the variance of technology news shocks or their transmission to real activity and inflation has changed over time. However, I detect significant time variation in the endogenous monetary policy reaction to technology news shocks; responding strongly to inflation most of the time, but less during the Great Inflation period. The evidence of this paper thus supports the hypothesis that the high inflation rates of the mid and late 1970s were the result of bad policy rather than bad luck.