A note on poor-institution traps in international fiscal policy games

This note explores the link between the effort level to strengthen institutional quality and the nature of the fiscal policy game among interdependent economies plagued by corruption. Every country has a lower incentive to improve public governance when the effort made abroad to remedy institutional deficiencies becomes weaker. More importantly, the model highlights a possible trade-off between fighting corruption in interrelated developing countries and promoting fiscal policy coordination among them: cooperation goes together with the acceptance of more corruption. It follows that poor-institution traps can be Pareto-improving.Corruption; Fiscal policy; International coordination

Hugues Faure, 1928–2003: The unique adventure of his life

Hugues Faure was not only one of the greatest pioneers of the study of the Quaternary and a man of outstanding personality, with the highest integrity, an uncommon strength of character, with a lot of kindness and generosity, but also a man who made his dreams, conceived in the inhospitable solitudes of the Sahara, come true. He was very young when he chose his way: barely 10 years old and his passion for geology already filled his life. It was in Africa, a continent he discovered at his earliest years as a field-geologist, and deeply loved, that he nursed and matured many of his most stimulating ideas on Quaternary environmental change. It was in the desert that he built up his exceptional personality and found his truth, which finally allowed him to accomplish his destiny. Hugues Faure was born in Paris, on the 11th March 1928, the son of a jeweller. The comfortable circumstances of the family were darkened by his father's death when Hugues was only 3 years old. As a consequence of this sad event, Hugues used to spend in England most of his school holidays far from his family. Then during World War 2, he lived the exodus on the roads of France, cycling under the bombs, with his dog in his basket. He was 12 years old, and it was the end of his youth. His passion for earth sciences had began before the age of ten, when he started collecting flint and fossils from the chalk of the Paris Basin, and decided to stop playing piano, so as to devote himself to Geology. Hugues graduated in Mathematics from Lycée Jacques-Decour in 1948, and in Sciences from the Faculté des Sciences de Paris Sorbonne in 1949. On the same year he enrolled as a geologist of the “France of Overseas”, then as a hydrogeologist at the French Geological Survey (BRGM) (1949–1963), so as to work in Africa

Electron-impact rotational excitation of symetric-top molecular ions

We present electron-impact rotational excitation calculations for polyatomic molecular ions. The theory developed in this paper is an extension of the work of Rabadán et al (Rabadán I, Sarpal B K and Tennyson J 1998 J. Phys. B: At. Mol. Opt. Phys. 31 2077) on linear molecular ions to the case of symmetric-top species. The H3+ and H3O+ ions, as well as their deuterated forms D3+ and D3O+, are used as test cases and cross sections are obtained at various levels of approximation for impact energies up to 5 eV. As in the linear case, the widely used Coulomb–Born (CB) approximation is found to be unreliable in two major aspects: transitions with ΔJ > 1 are entirely dominated by short-range interactions and threshold effects are important at very low energies. Electron collisional selection rules are found to be consistent with the CB theory. In particular, dominant transitions are those for which ΔJ ≤ 2 and ΔK = 0

Horocyclic invariance of Ruelle resonant states for contact Anosov flows in dimension 3

We show that for smooth contact Anosov flows in dimension 3, the resonant states associated to the first band of Ruelle resonances are distributions that are killed by the unstable derivative.Comment: 23 page

Convergence of generalized urn models to non-equilibrium attractors

Generalized Polya urn models have been used to model the establishment dynamics of a small founding population consisting of k different genotypes or strategies. As population sizes get large, these population processes are well-approximated by a mean limit ordinary differential equation whose state space is the k simplex. We prove that if this mean limit ODE has an attractor at which the temporal averages of the population growth rate is positive, then there is a positive probability of the population not going extinct (i.e. growing without bound) and its distribution converging to the attractor. Conversely, when the temporal averages of the population growth rate is negative along this attractor, the population distribution does not converge to the attractor. For the stochastic analog of the replicator equations which can exhibit non-equilibrium dynamics, we show that verifying the conditions for convergence and non-convergence reduces to a simple algebraic problem. We also apply these results to selection-mutation dynamics to illustrate convergence to periodic solutions of these population genetics models with positive probability.Comment: 29 pages, 2 figure

Consistency of vanishing smooth fictitious play

We discuss consistency of Vanishing Smooth Fictitious Play, a strategy in the context of game theory, which can be regarded as a smooth fictitious play procedure, where the smoothing parameter is time-dependent and asymptotically vanishes. This answers a question initially raised by Drew Fudenberg and Satoru Takahashi.Comment: 17 page