The impact of the residential sphere on the territorial development (In French)

The residential sphere is developing according to householders localization and revenue. The sphere division (residential, productive and public) is difficult to apply because the frontiers are blurred, but it is useful to take into account new economic evolutions.\r\nThe residential sphere share is growing quickly in the global employment in France since 1990 to the detriment of the of the productive sphere share. This movement exists also in all regions and in numerous employment areas. It is explained by internal factors (productivity, consumption structure) and external factors (international competition). This economy is more important in the South and in the West of France which are more attractive for households. \r\nThe residential sphere contributes to economic development by numerous employment creations and best ability to resist to globalisation shocks; it leads often to reduction of inequality between territories. But this contribution is limited because productivity growth, wage level and job quality are lowest than in productive sphere. Residential growth cannot be generalized and his future depends of the continuity of growth of householders mobility and public and social budgets. \r\nresidential sphere, Productive sphere; employment, territories, development

The Core of the Participatory Budgeting Problem

In participatory budgeting, communities collectively decide on the allocation of public tax dollars for local public projects. In this work, we consider the question of fairly aggregating the preferences of community members to determine an allocation of funds to projects. This problem is different from standard fair resource allocation because of public goods: The allocated goods benefit all users simultaneously. Fairness is crucial in participatory decision making, since generating equitable outcomes is an important goal of these processes. We argue that the classic game theoretic notion of core captures fairness in the setting. To compute the core, we first develop a novel characterization of a public goods market equilibrium called the Lindahl equilibrium, which is always a core solution. We then provide the first (to our knowledge) polynomial time algorithm for computing such an equilibrium for a broad set of utility functions; our algorithm also generalizes (in a non-trivial way) the well-known concept of proportional fairness. We use our theoretical insights to perform experiments on real participatory budgeting voting data. We empirically show that the core can be efficiently computed for utility functions that naturally model our practical setting, and examine the relation of the core with the familiar welfare objective. Finally, we address concerns of incentives and mechanism design by developing a randomized approximately dominant-strategy truthful mechanism building on the exponential mechanism from differential privacy

On the global well-posedness of discrete Boltzmann systems with chemical reaction

Classificação AMS: 76P05, 35A05, 35L50We study an initial-boundary value problem in one-space dimension for the discrete Boltzmann equation extended to a diatomic gas undergoing both elastic multiple collisions and chemical reactions. By integration of conservation equations, we prove a global existence result in the half-space for small initial data $\,N_0\in\,\mathcal{B}^1_+\cap L^1$.Fundação para a Ciência e a Tecnologia (FCT) - Programa Operacional "Ciência, Tecnologia, Inovação" (POCTI)

What medium-term growth rates after the crisis?

The financial crisis originated in the United States in 2007 and, then, spread in all the economies of the world. After a drop in activity of historic magnitude, first signs of recovery were recorded in 2009. However, our study of previous banking crises that have taken place in OECD countries over the last forty years leads one to expect a very gradual return of growth rates to their pre-crisis values, with long-lasting losses for the level of GDP. According to our estimations, average losses observed during past banking crises occurred through a reduction in capital stocks, an increase in unemployment rates and a drop in participation rates. Conversely, past banking crises seemed to have had little impact on total factor productivity. In France, the 1992-1993 crisis, which shares some common features with the current crisis, had also long-lasting negative impacts on the employment and unemployment rates. Employment-rate losses were fairly similar for men and women. Ten years passed before the overall unemployment rate returned to its pre-crisis level. Based on various post-crisis scenarios, we illustrate the mechanical medium-term impact of the current crisis on public finances, whithout any fiscal adjustment after 2012. Even in the scenario of a complete recovery by 2018 of GDP losses recorded in 2008 and 2009, the impact on the public debt would exceed 20 % of GDP ten years after the crisis as a result of declining revenues and increasing interest payments. The impact would be still higher in less favourable scenarios.financial crisis, medium-term growth

The impact of the residential sphere on the territorial development (In French)

The residential sphere is developing according to householders localization and revenue. The sphere division (residential, productive and public) is difficult to apply because the frontiers are blurred, but it is useful to take into account new economic evolutions.\r\nThe residential sphere share is growing quickly in the global employment in France since 1990 to the detriment of the of the productive sphere share. This movement exists also in all regions and in numerous employment areas. It is explained by internal factors (productivity, consumption structure) and external factors (international competition). This economy is more important in the South and in the West of France which are more attractive for households. The residential sphere contributes to economic development by numerous employment creations and best ability to resist to globalisation shocks; it leads often to reduction of inequality between territories. But this contribution is limited because productivity growth, wage level and job quality are lowest than in productive sphere. Residential growth cannot be generalized and his future depends of the continuity of growth of householders mobility and public and social budgets. \r\nresidential sphere, Productive sphere; employment, territories, development

The MESANGE model: re-estimation on National Accounts base 2000 / Part 2 Version with chained-linked volumes

Mesange is a medium-size quarterly macro-econometric model of the French economy (about 500 equations, three sectors). The model describes short-term Keynesian dynamics and its long-term equilibrium is driven by supply-side determinants. Its reestimation on data from the national accounts base 2000 with fixed-base volumes is presented in a recent working paper (Klein and Simon, 2010). This first version of the model has been optimized for simulation use. Other applications of the Mesange model (short-term forecasting, analyses of the past) required its adaptation to the published data from the quarterly accounts with chained-linked volumes, as well as the integration of the recent crisis episode. A second version of the Mesange model has, therefore, been developed for this purpose. This version is presented in this working paper. First, the problems raised for macroeconomic modelling by national accounts with chained-linked volumes are explained and the solutions chosen to adapt the model to these new conventions are discussed. The applications of the version of the model with chained-linked volumes are, then, explained and illustrated with examples. Last, the main reestimated equations are detailed. The differences with respect to the version of the model with fixed-base volumes are commented. They stem from estimations based on non-identical data, but also from the different uses made of the two versions of Mesange and the resulting various needs and constraints that have conditioned the methodological choices that have been made. As for the version of the model with chained-linked volumes, priority has been given to the quality of the adjustment to the data rather than to the underlying theoretical framework. Nonetheless, the philosophy and general structure of the two versions of the model remain very much alike.macroeconometric model, estimation, chained-linked volumes, short-term forecasting, contribution analysis

Multidimensional simple waves in fully relativistic fluids

A special version of multi--dimensional simple waves given in [G. Boillat, {\it J. Math. Phys.} {\bf 11}, 1482-3 (1970)] and [G.M. Webb, R. Ratkiewicz, M. Brio and G.P. Zank, {\it J. Plasma Phys.} {\bf 59}, 417-460 (1998)] is employed for fully relativistic fluid and plasma flows. Three essential modes: vortex, entropy and sound modes are derived where each of them is different from its nonrelativistic analogue. Vortex and entropy modes are formally solved in both the laboratory frame and the wave frame (co-moving with the wave front) while the sound mode is formally solved only in the wave frame at ultra-relativistic temperatures. In addition, the surface which is the boundary between the permitted and forbidden regions of the solution is introduced and determined. Finally a symmetry analysis is performed for the vortex mode equation up to both point and contact transformations. Fundamental invariants and a form of general solutions of point transformations along with some specific examples are also derived.Comment: 21 page