Was the increase in income inequality in the US due to permanent shocks or merely to anincrease in the variance of transitory shocks? The implications for consumption and welfaredepend crucially on the answer to this question. We use CEX repeated cross-section data onconsumption and income to...

We prove that for any incomplete market and any concave utilityfunction the marginal propensities to consume and to save are alwayspositive. Furthermore, we introduce a class of incomplete markets thatincludes almost all well known examples of market incompleteness infinance and macroeconomics....

We prove that in a closed economy without distortionary taxation, the welfare of a representativeconsumer is summarized to a …rst order by the current and expected future values of the Solowproductivity residual in level and by the initial endowment of capital. The equivalence holds if...