Publisher:
The Johns Hopkins University, Department of Economics, Baltimore, MD
Abstract:
Several authors have argued that if the labor share of income is used as the proxy for real marginal cost, then the sticky-price version of the New Keynesian Phillips Curve does a good job of approximating US inflation dynamics. However, this paper argues that the labor share is an inappropriate measure of real marginal cost for two reasons: it is countercyclical whereas theory predicts marginal cost should be procyclical, and it employs a counterfactual assumption about the behavior of labor over the business cycle. Relaxing this assumption to a more realistic one leads to a measure of marginal cost that is markedly procyclical. Testing this improved measure of marginal cost then produces results that are contradictory to the entire underlying model of the NKPC. Thus I conclude that the NKPC fails to give a sound explanation of inflation dynamics.