Sebastien Buttet

A Simple Treatment of the Liquidity Trap for Intermediate Macroeconomics Courses

Several leading undergraduate intermediate macroeconomics textbooks now include a simple reduced-form New Keynesian model of short-run dynamics (alongside the IS-LM model). Unfortunately, there is no accompanying description of how the zero lower bound on nominal interest rates affects the model. In this article, the authors show how the aforementioned model can easily be modified to teach undergraduate students about the significance of the zero lower bound for economic performance and policy. This acquires additional significance because economies such as the United States and Japan have been close to the zero lower bound since 2008 and 1995, respectively. The authors show that when the zero lower bound is introduced, an additional long-run equilibrium exists. This equilibrium is unstable and can lead to a deflationary spiral.

Toward a quantitative theory of food consumption choices and body weight

We propose a calibrated dynamic model of food consumption choices and body weight to study changes in daily caloric intake, weight, and the away-from-home share of calories consumed by adult men and women in the U.S. during the period between 1971 and 2006. Calibration reveals substantial preference heterogeneity between men and women. For example, utility losses stemming from weight gains are ten times greater for women compared to men. Counterfactual experiments show that changes in food prices and household income account for half of the increase in weight of adult men, but only a small fraction of womens weight. We argue that quantitative models of food consumption choices and body weight have a unique role to play in future research in the economics of obesity.

Macroeconomic Stabilization When The Natural Real Interest Rate Is Falling

The authors modify the Dynamic Aggregate Demand-Dynamic Aggregate Supply model in Mankiws widely used intermediate macroeconomics textbook to discuss monetary policy when the natural real interest rate is falling over time. Their results highlight a new role for the central banks inflation target as a tool of macroeconomic stabilization. They show that even when the zero lower bound is not binding, a prudent central bank must match every decrease in the natural real interest rate with an equal increase in the target rate of inflation in order to stabilize the risk of the economy falling into a deflationary spiral, which is an acute case of simultaneously falling output and inflation in which the economys self-correcting forces are inactive.