Nash-implementation of competitive equilibria via a bounded mechanismJournal articleGaël Giraud and Hubert Stahn, Review of Economic Design, Volume 17, Issue 1, pp. 43-62, 2013

We deal with the problem of providing incentives for the implementation of competitive outcomes in a pure-exchange economy with finitely many households. We construct a feasible price-quantity mechanism, which fully implements Walras equilibria via Nash equilibria in fairly general environments. Traders’ preferences need neither to be ordered nor continuous. In addition, the mechanism is such that no pure strategy is weakly dominated, hence is bounded (in the sense of Jackson 1992 ). In particular it makes no use of any integer game. Copyright Springer-Verlag Berlin Heidelberg 2013

Potential Conflict and Inefficiencies Arising in Agri-environmental ManagementJournal articleElsa Martin and Hubert Stahn, Journal of Agricultural Economics, Volume 64, Issue 2, pp. 423-445, 2013

We characterise the welfare implications of uncoordinated policy decisions in the presence of multiple externalities, illustrated with an aquifer. We concentrate on the problem of coordination that can occur when distinct agricultural and water authorities implement their respective policies (to optimise food production and groundwater use) with environmental concerns in mind. We represent this problem as an open-loop Nash game, which compares the game-theoretical solution to a centrally planned solution. We show that the inefficiencies arise from differences in the account taken of relevant costs by different authorities. We demonstrate that the magnitude of the inefficiency generated by the absence of coordination of our authorities varies depending on the weights put on environmental benefits by each authority, and discuss the implications of analysis for future research and policy.

Doit-on réguler l'appropriation des connaissances ?Journal articleHubert Stahn and Elsa Martin, Revue d'économie politique, Volume 122, Issue 4, pp. 599-623, 2012

In this work, we propose to look at the stock of knowledge that can be patented by private labs. We consider this stock as a common. It changes over time according to the number of patents and to a by-product of the University research activity. We first show that the competition between strategic labs generate, in the short run, an over-extraction of the stock of knowledge. This reduces, in the long run, the patent activity. We finally show that the taxation of patents is an efficient tool in order to regulate the knowledge privatization process.

Waste Management and Household Effort: Toward an Enhanced ADF PolicyJournal articleStéphanie Lemaitre and Hubert Stahn, Annals of Economics and Statistics, Issue 107-108, pp. 133-152, 2012

Advance Disposal Fees (ADF) are quite popular in waste management policies, but they discourage any waste reduction effort at the household level. We propose a tiered ADF policy that enhances this system by giving households the possibility to sign a waste reduction contract in return for a lower fee. These contracts satisfy incentive, budget-balancing and participation constraints. For these feasible contracts, we show that the enriched ADF policy is welfare improving and always induces a waste reduction effort.

Voluntary agreements with Industries - participation incentives with industry-wide targets: a commentJournal articleHubert Stahn and Anne-sarah Chiambretto, Economics Bulletin, Volume 31, Issue 1, pp. 116-121, 2011

This comment reexamines the problem of free-riding in pre-emptive collective environmental voluntary agreements (VA) analysed by Dawson and Segerson in the context of VAs with a global emission target and a pigouvian tax used as a threat. Completely remaining in the authors' framework, we here reconsider their results about efficiency. While they claim it provides the optimal amount of environmental quality but inefficiently, we show that there exists an optimal threat under which the equilibrium of the game is a cost-effective VA. This result gives an additional indication on the way VAs should be used to be efficient.

Should we reallocate patent fees to the universities?Journal articleHubert Stahn and Elsa Martin, Economics of Innovation and New Technology, Volume 20, Issue 7, pp. 681-700, 2011

In knowledge economies, patent agencies are often viewed as a relevant instrument of an efficient innovation policy. This paper brings a new support to that idea. We claim that these agencies should play an increasing role in the regulation of the relation between private R&D labs and public fundamental research units especially concerning the question of the appropriation of free usable research results. Since these two institutions work with opposite institutional arrangements (see P.S. Dasgupta and P.A. David. 1987. Information disclosure and the economics of science and technology. In Arrow and the accent of modern economic theory , ed. G.R. Feiwel, 519–42. New York: State University of New York Press), we essentially argue that there is, on the one hand, an over-appropriation of these results while, on the other hand, there is also an under-provision of free usable results issued from more fundamental research. We show how a public patent office can restore efficiency.

Individuals doubts and policy implementation: Risk premium and contingent valuationJournal articleHubert Stahn and Agnès Tomini, Environmental Economics, Volume 2, Issue 2, pp. 8-18, 2011

This paper is concerned with discrete choice contingent value estimate when the respondents are uncertain about the environmental amenities. Within a class of indirect utility functions often used in empirical studies, the authors put forwards the effect of the risk premium on the willingness to pay (WTP). Then, it is shown how this risk premium also
modifies the estimation procedure. A Monte Carlo simulation concludes the paper by putting forward a misestimation of the WTP. When this uncertainty is ignored, more precisely, the authors focus on the effect of the risk premium.

Pourrait-on réallouer des redevances acceptables de pompage de l'eau souterraine de la Crau à l'association d'irrigants de la zone ?Journal articleHubert Stahn and Elsa Martin, Revue d'économie régionale et urbaine, Issue 3, pp. 517-548, 2009

Many aquifers, such as the Crau one, located in South-East of France, are not only exploited in order to satisfy human needs but are also replenished thanks to some farmers who are irrigating their crops according to old practices. Because of the positive externality hence induced, groundwater management is much more complicated than as usual, when only the withdrawals have to be slowed down. It is why we are going to consider in a new way the role of a local agency which is going to be in charge of the aquifer management. We will show that she can always implement a global fiscal scheme both being able to slow down the aquifer overexploitation by different non-atomistic users and to induce its optimal replenishment thanks to a watering association activity.

On Shapley-Shubik equilibria with financial marketsJournal articleGaël Giraud and Hubert Stahn, Economic Theory, Volume 35, Issue 3, pp. 469-496, 2008

No abstract is available for this item.

Environmental Taxation and Vertical Cournot Oligopolies: How Eco-industries MatterJournal articleJoan Canton, Antoine Soubeyran and Hubert Stahn, Environmental & Resource Economics, Volume 40, Issue 3, pp. 369-382, 2008

No abstract is available for this item.