Near-Rationality, Heterogeneity, and Aggregate Consumption

The simple permanent-income model provides a good description of the medium-long run behavior of aggregate non-durables consumption, but fails to describe its short run behavior. In this paper I, present a non-representative agent model with near-rational macroeconomic units a la Akerlof-Yellen that simultaneously explains the observed excess smoothness of consumption to wealth innovations and the excess sensitivity of consumption to lagged income changes. This models also explains conditional asymmetries found in the data: in good times, consumers respond more promptly to positive than negative wealth shocks; while the opposite is true in bad times. In spite of the presence of large non-diversifiable idiosyncratic uncertainty, the estimated dollar equivalent utility cost of the macroeconomic near-rational strategy required to explain the aggregate facts is only about 0.037 percent of consumption per year, where [gamma] is the coefficient of relative risk aversion. Copyright 1995 by Ohio State University Press.