More research is needed into why France’s education system is failing the country’s growing multicultural population

France has a history of universal education that stretches back more than a century. However, this system has been marred in recent years by a decrease in student achievement, and recent reforms to address this problem have been less than effective. Paola Mattei calls into question the French education system’s ‘republican’ foundations and argues that further research is needed into the social and economic reasons why some students have lower educational outcomes

Multiplying a Gaussian Matrix by a Gaussian Vector

We provide a new and simple characterization of the multivariate generalized Laplace distribution. In particular, this result implies that the product of a Gaussian matrix with independent and identically distributed columns by an independent isotropic Gaussian vector follows a symmetric multivariate generalized Laplace distribution

Empirical Evaluation of Real World Tournaments

Computational Social Choice (ComSoc) is a rapidly developing field at the intersection of computer science, economics, social choice, and political science. The study of tournaments is fundamental to ComSoc and many results have been published about tournament solution sets and reasoning in tournaments. Theoretical results in ComSoc tend to be worst case and tell us little about performance in practice. To this end we detail some experiments on tournaments using real wold data from soccer and tennis. We make three main contributions to the understanding of tournaments using real world data from English Premier League, the German Bundesliga, and the ATP World Tour: (1) we find that the NP-hard question of finding a seeding for which a given team can win a tournament is easily solvable in real world instances, (2) using detailed and principled methodology from statistical physics we show that our real world data obeys a log-normal distribution; and (3) leveraging our log-normal distribution result and using robust statistical methods, we show that the popular Condorcet Random (CR) tournament model does not generate realistic tournament data.Comment: 2 Figure

El arte y los nuevos medios en Italia Title: Art and New Media in Italy

Maria Grazia Mattei (1950-), Italian expert in new communications technology, founder of MGM Digital Communication, with remarks by artist Fabrizio Plessi.Abstract: Maria Grazia Mattei (1950 -), experta italiana en la nueva tecnología de las comunicaciones, fundadora de MGM Digital Communication, con notas del artista Fabrizio Plessi.Culture & Arts, Cultural Center Encuentros Nro. 45 Maria Grazia Mattei Art and New Media in Italy

Ultra High Energy Cosmic Rays from charged black holes. A new theoretical possibility?

In General Relativity, there is a new field of activity concerning the study of charged stars. In a recent paper, Ray et al. have shown the possibility that the collapse of a charged star could form a charged black hole before all the charge leaves the system. In this field of view we propose a new model for UHECR and we will show that it is possible to accelerate cosmic rays up to EeV. In this talk we will compute the UHECR flux, the charged black hole density and the energy spectrum associated with them in order to reproduce experimental data. We will see that we need only a small number of these hidden sources in order to account for observed UHECR properties and we will study the limits on charge and mass of black holes.Comment: 4 pages, 2 figure

Application of the Generalized Propensity Score. Evaluation of public contributions to Piedmont enterprises.

In this article, we apply a generalization of the propensity score of Rosenbaum and Rubin (1983b). Techniques based on the propensity score have long been used for causal inference in observational studies for reducing bias caused by non-random treatment assignment. In last years, Joffe and Rosenbaum (1989) and Imbens and Hirano (2000) suggested two possible extensions to standard propensity score for ordinal and categorical treatments respectively. Propensity score techniques, allowing for continuous treatments effect evaluation, were, instead, recently proposed by Van Dick Imai (2003) and Imbens and Hirano (2004). We refer to Imbens' approach for the use of the generalized propensity score, to widen its application for continuous treatment regimes.

Exact Dimensionality Selection for Bayesian PCA

We present a Bayesian model selection approach to estimate the intrinsic dimensionality of a high-dimensional dataset. To this end, we introduce a novel formulation of the probabilisitic principal component analysis model based on a normal-gamma prior distribution. In this context, we exhibit a closed-form expression of the marginal likelihood which allows to infer an optimal number of components. We also propose a heuristic based on the expected shape of the marginal likelihood curve in order to choose the hyperparameters. In non-asymptotic frameworks, we show on simulated data that this exact dimensionality selection approach is competitive with both Bayesian and frequentist state-of-the-art methods

The Global Legal Standards Report

The IUC Independent Policy Report was drafted by the “IUC Legal Standards Research Group," organized by a Steering Committee chaired by Ugo Mattei (International University College of Turin), coordinated by Edoardo Reviglio (International University College of Turin) and Giuseppe Mastruzzo (International University College of Turin), and composed by Franco Bassanini (University of Rome “La Sapienza"), Guido Calabresi (Yale University), Antoine Garapon (Institut des Hautes Etudes sur la Justice, Paris), and Tibor Varady (Central European University, Budapest). Contributors include Eugenio Barcellona (Eastern Piedmont University), Mauro Bussani (University of Trieste), Giuliano G. Castellano (Ecole Polytechnique, Preg/CRG), Moussa Djiré (Bamako University), Liu Guanghua (Lanzhou University), Golnoosh Hakimdavar (University of Turin), John Haskell (SOAS), Jedidiah J. Kroncke (Yale Law School), Andrea Lollini (Bologna University), Alberto Lucarelli (Federico II University), Boris N. Mamlyuk, (University of Turin), Alberto Monti (Bocconi University), Sergio Ariel Muro (Torquato di Tella University), Domenico Nicolò (Mediterranean University of Reggio Calabria), and Nicola Sartori (University of Michigan).