We implement a new approach for the identification of "news shocks" about future technology. In a VAR featuring a measure of aggregate technology and several forward-looking variables, we identify the news shock as the shock orthogonal to technology innovations that best explains future...

This paper is a non-technical and somewhat philosophical essay, that seeks to investigate the relationship between economics and reality. More precisely, it asks how reality in the form empirical evidence does or does not influence economic thinking and theory. In particular, which role do...

What drives countercyclical volatility? A large literature has documented that many economic variables are more disperse in recessions, but this could either occur because shocks get bigger or because firms respond more to shocks which are the same size. Existing evidence that the dispersion of...

We develop a framework to estimate the aggregate capital-labor elasticity of substitution by aggregating the actions of individual plants, and use it to assess the decline in labor's share of income in the US manufacturing sector. The aggregate elasticity reflects substitution within plants and...

The Real Business Cycle (RBC) research program has grown spectacularly over the last decade, as its concepts and methods have diffused into mainstream macroeconomics. Yet, there is increasing skepticism that technology shocks are a major source of business fluctuations. This chapter exposits the...

This paper studies how stable over time are the so-called "structural parameters" of dynamic stochastic general equilibrium (DSGE) models. To answer this question, we estimate a medium-scale DSGE model with real and nominal rigidities using U.S. data. In our model, we allow for parameter...

This paper starts from two sets of facts about Continental Europe.The first is the steady increase in unemployment since the early 1970s. The second is the evolution of the capital share, an initial decline in the 1970s, followed by a much larger increase since the mid-1980s. The paper then...

Dynamic optimizing models with an IS-LM-type structure and slow price adjustments have been used for much recent monetary policy analysis, but usually with capital and investment treated as exogenous a significant restriction. This paper demonstrates that investment decisions can be endogenized...

This paper reviews the role of temporary price and wage rigidities in explaining the dynamic relationship between money, real output, and inflation. It summarizes microeconomic data on price and wage setting behavior, and argues that staggered price and wage setting models provide the most...

Ideas are different from nearly all other economic goods in that they are nonrivalrous. This nonrivalry implies that production possibilities are likely to be characterized by increasing returns to scale, an insight that has profound implications for economic growth. The purpose of this chapter...