Bertrand Wigniolle

Cash-in-advance constraints, bubbles and monetary policy

In this paper, we study the equilibrium dynamics of an overlapping generations model with capital, money and cash-in-advance constraints. At each period, the economy can experience two different regimes: either the cash-inadvance constraint is binding and money is a dominated asset, or the constraint is strictly satisfied and money has the same return as capital. When the second regime occurs, we say that the economy experiences a temporary bubble. We show the existence of temporary bubbles, and we prove that cyclical equilibria may exist. In these equilibria, the economy experiences some periods without bubbles and some periods with bubbles. We also show that monetary creation can be used in order to eliminate temporary bubbles.

Pareto-Efficiency and Endogenous Fertility: A Simple Model

Pareto-efficiency of the competitive equilibrium is studied for a simple economy with overlapping generations and endogenous fertility. For CES utility and production functions, the properties of the economy are closely related to the two elasticities of substitution. The competitive equilibrium exists and is unique if the sum of the two elasticities is not less than one. For certain parameters, the equilibrium is both in under-accumulation and inefficient. When the sum of the two elasticities is greater than two, an equilibrium converging in under-accumulation is Pareto-efficient.

Fertility in the absence of self-control

This paper studies the quantity–quality trade-off model of fertility, under the assumption of hyperbolic discounting. It shows that the lack of self-control may play a different role in a developed economy and in a developing one. In the first case, characterized by a positive investment in quality, the lack of self-control may tend to reduce fertility. In the second case, it is possible that the lack of self-control leads to both no investment in quality and a higher fertility rate. It is also proved that if parents cannot commit on their investment in quality, a small change of parameters may lead to a jump in fertility and education.