Instrumental variables (IV) estimation of a demand equation using time series data is shown to produce a weighted average derivative of heterogeneous potential demand functions. This result adapts recent work on the causal interpretation of two-stage least squares estimates to the simultaneous...

Sir John Hick's Value and Capital provided the theoretical foundation for an important element of modern macroeconomics. Intertemporal substitution - deferral or acceleration of economic activity in response to the real interest rate and other incentives - is the mechanism generally relied upon...

Macroeconomic research on consumption has been influenced profoundly by rational expectations. First, rational expectations together with the hypothesis of constant expected real interest rates implies that consumption should evolve as a random walk. Much of the research of the past decade has...

We analyze the implications of household-level adjustment costs for the dynamics of aggregate consumption. We show that an economy in which agents have ldquo;consumption commitmentsrdquo; is approximately equivalent to a habit formation model in which the habit stock is a weighted average of...

Standard consumption models assume a notional consumption flow that does not distinguish between nondurable and durable consumption. Such notional-consumption models generate notional marginal propensities to consume (MPC). By contrast, empirical work and policy discussions often highlight...