Indivisibility, irreversibility, and the demand for consumer durables

Abstract

A deeper understanding of the volatility of expenditures on consumer durables is sought in the properties of those goods and the transactions by which they are acquired: durability, indivisibility, and irreversibility. When these properties constrain optimization we find: 1) variation in the lengths of endogenously determined replacement cycles rather than stock-level adjustments may account for much of the volatility, 2) the qualitative nature of an individual consumer's response to a shock depends on the age of his existing unit relative to its optimal replacement age when the shock occurs, 3) the aggregate distribution of unit ages relative to their optimal replacement ages conditions the aggregate response to shocks, and 4) shocks actually change that distribution. A simple aggregation methodology is demonstrated which depicts exaggerated aggregate reactions to shocks.