Jean-Pierre Amigues

Resource-augmenting R&D with heterogeneous labor supply

The effective labor possibilities frontier (ELPF) is defined as the set of statically efficient allocations of labor inputs in the competing tasks of production and R&D. It is concave if labor is heterogeneous. In an R&D-based growth model with an essential non-renewable natural resource, the shape of the ELPF affects the optimal speed of the transition. If resource endowment is poor, transition is slower and involves a smaller R&D effort, and slower growth in per capita consumption, in the case of a heterogeneous labor force as compared to a homogeneous one. Policies that modify the distribution of skills in the population imply shifts of the ELPF. We provide a taxonomy of possible shifts of the ELPF, and link them to education policy or demographic trends.

De l'usage optimal de divers types de ressources naturelles

A partial equilibrium analysis shows that a pool of natural resources with constant unit costs of extraction has to be exploited in strict increasing cost order. Kemp and Long [1980] have shown that it is not necessarily the case in a general equilibrium framework. In a consumption-leisure trade-off model, we show that the optimal order of exploitation is never strict, and that for a set of model parameters, the resources exploitation paths may be inderteminate although the consumption-leisure paths are perfectly determinated.

Rational pricing of groundwater with a growing population

When population is increasing, characterizing the optimal water consumption path is complicated by the fact that the underlying dynamics of the water stock is contingent on the level of the stock itself. We propose a method of constructing the optimal path in this case. Since population is increasing, the optimal consumption path may involve refraining at times from consuming the totality of the surface water flow in order to restock in groundwater for future consumption. The aquifer then serves as a means to achieve welfare increasing intertemporal transfers of surface water. Therefore the aquifer itself, as distinct from the stock of water it serves to store, may have value and the marginal valuation of water when groundwater stocks are being drawn upon should, for this reason, differ at times from the marginal valuation of water when it is drawn strictly from surface water.

Bertrand and Cournot Equilibrium Price Paths in a Nonrenewable Resource Differentiated Product Duopoly

In this paper, we report on some results concerning the comparison of Cournot and Bertrand equilibrium price paths in the case of a differentiated nonrenewable resource extraction duopoly. In the Cournot model of oligopoly the strategy variables of the firms are the quantities produced. In the Bertrand model, on the other hand, prices are the strategy variables.

De quelques spécificités de la valorisation des ressources naturelles semi-renouvelables

We study the optimal valuation of semi-renewable resources, like groundwater, under different assumptions as to the evolution of the population. When the population is either constant or decreasing, valuations of flow and stock resources are identical. With an increasing population however, an optimal consumption policy may involve refraining from consuming the flow in order to restock for future consumption. In this case, the marginal valuation of the resource as a flow or as a stock may differ at times.

Gravières et vins de Bordeaux

Sand and gravel mining is one of the main extractive industries in France. Extraction implies generally a loss of some agricultural potential, i.e. the destruction of some agricultural asset. Such a problem has recently arisen in the Bordeaux area, well known for its wine. In this paper, we show how the gravel extraction and agricultural output paths will be determined in a system of competitive markets.