Many authors have found that the capital asset pricing model (CAPM) does not explain stock returns—possibly because it is only a special case of Merton's (1973) intertemporal CAPM under the assumption of constant investment opportunities (e.g., a constant expected equity premium). This paper explains the progress that has been made by dropping the assumption that expected returns are constant. First, the evidence on the predictability of returns is summarized; then, an example from Campbell (1993) is used to show how time-varying expected returns can lead to the rejection of the CAPM.
The authors study the welfare cost of inflation in a general equilibrium life-cycle model that includes households that live for many periods, production and capital, simple monetary and financial sectors, and a fairly elaborate government sector. The government's taxation of capital income is not indexed for inflation. They find that a plausibly calibrated version of this model has a steady state that matches a variety of facts about the postwar U.S. economy. They use the model to estimate the welfare cost of permanent, policy-induced changes in the inflation rate and find that most of the costs of inflation are direct and indirect consequences of the fact that inflation increases the effective tax rate on capital income. The cost estimates are an order of magnitude larger than other estimates in the literature.
This article analyzes how announced surprises in monetary policy actions and macroeconomic data releases affect the average rate of inflation that economic agents expect to prevail over the 10-year period following the surprise. The analysis also addresses the effect of Federal Reserve communication and surprises in monetary policy actions on perceived inflation risk over this 10-year period. The study shows that surprises in macroeconomic data releases and monetary policy actions indeed affect the expected rate of inflation. Further, there is evidence that surprises in monetary policy actions increase perceived inflation risk, whereas Federal Reserve communication reduces it.