Life-Cycle Portfolio Choice with Liquid and Illiquid Financial Assets

Traditionally quantitative models that have studied households' port- folio choice have focused exclusively on the different risk properties of alternative financial assets. In the present paper we take a different ap- proach and assume that assets also differ in their liquidity. We construct a model where agents face uninsurable idiosyncratic shocks to labor earn- ings. Earnings are paid in the form of a liquid asset that is needed to buy consumption goods. A second, risky asset, called stock is also available, however a fixed transaction cost is needed to buy or sell this asset. When the transaction cost is calibrated to match the observed infrequency in households' trading, the model generates patterns of portfolio stock allo- cations over age and wealth that are constant or moderately increasing, thus more in line with the empirical evidence compared to conventional models.