Reinforcing the patent system? Effects of patent fences and knowledge diffusion on the development of new industries, technical progress and social welfare

This article extends the industry dynamics model of Vallée & Yildizoglu (2006) in order to carry out a richer theoretical analysis of the consequences of a stronger patent system. This model explicitly takes into account the potentially positive effects of patents: publication of patents participates to the building of a collective knowledge stock on which new innovations can rely, and dropped patents can provide a source of technological progress for firms that are lagging behind the leaders of the industry. These dimensions of the patent system are used to question the negative results of Vallée & Yildizoglu (2006). The main results of the new model show that these positive effects do not counterbalance the negative effects of a stronger patent system on social welfare and global technological progress, even if it is a source of better protection and higher profits for the firms. The model also considers the effect of patents on the survival of the newly founded industries and on their development.Innovation, Technical progress, Patent system, Intellectual property rights (IPR), Technology policy

Learning the optimal buffer-stock consumption rule of Carroll

This article questions the rather pessimistic conclusions of Allen et Carroll (2001) about the ability of consumer to learn the optimal buffer-stock based consumption rule. To this aim, we develop an agent based model where alternative learning schemes can be compared in terms of the consumption behaviour that they yield. We show that neither purely adaptive learning, nor social learning based on imitation can ensure satisfactory consumption behaviours. By contrast, if the agents can form adaptive expectations, based on an evolving individual mental model, their behaviour becomes much more interesting in terms of its regularity, and its ability to improve performance (which is as a clear manifestation of learning). Our results indicate that assumptions on bounded rationality, and on adaptive expectations are perfectly compatible with sound and realistic economic behaviour, which, in some cases, can even converge to the optimal solution. This framework may therefore be used to develop macroeconomic models with adaptive dynamics.Consumption decisions; Learning; Expectations; Adaptive behaviour, Computational economics

Motivations and determinants of technological innovations. A theoretical survey (In French)

The aim of this paper is to present the theoretical literature dedicated to the analysis of the motivations and the determinants of firms\' technological innovations. To this end, we follow a strategy of presentation that starts with the simplest possible framework in which the innovation can occur (Robinson Crusoe economy), and that encompasses gradually richer economic contexts. The discussion is hence organized in a progressive logic, ranging from purely individual motivations and conditions of innovations (in the case of Robinson, alone on his island), towards the more complex case where the innovative activities take place in an international framework, under particular institutional configurations, depending on the considered countries. The intermediate stages successively introduce the following economic phenomena: demand, sectoral dimensions, competition, public authorities, and finally, international competition.Technological innovation, Industrial economics, Evolutionary economics