the Labor Market of Italian Politicians, Second Version

We analyze the career profiles of Italian legislators in the post-war period. Using a unique, newly collected dataset that contains detailed information on all the politicians who have been elected to the Italian Parliament between 1948 and 2008, we address a number of important issues that pertain to their career paths prior to election to Parliament, their parliamentary careers, and their post-Parliament employment. Our data span two institutional regimes: Italy’s First Republic (1948-1994) and the Second Republic (1994-present), characterized by different electoral rules and party structures. We first present a brief overview of the Italian political system. We then provide a comprehensive view of the career profiles of Italian legislators over the entire sample period, and highlight the major differences between the First and the Second Republic. We also compare the profiles of Italian legislators to those of the members of the United States Congress. We then use our data to address a number of questions that pertain to the selection of Italian politicians, their labor market, and their overall quality. We also draw some general conclusions that contribute to the debate about the relative efficacy and desirability of alternative policies regarding the selection and the compensation of elected representatives.politicians, parties, political careers

The Labor Market of Italian Politicians

Like voters (the represented), politicians (the representees) are the heart and soul of representative democracy. But isnt being a politician just like any other job? After we get past the rhetoric, is politics any different than other occupations? In the political sector, voters, parties and politicians represent the counterparts of consumers, firms and workers/managers in the market sector. In fact, the analogy is much deeper than it may appear at first sight. In the market sector, consumers determine to a large extent the success of a firm and ultimately the managements fate. However, managers are chosen by the firms, which typically have an objective that is different from those of consumers and managers. Likewise, while in all democratic systems the voters ultimately determine who is elected, it is typically the case that political parties nominate candidates for public office. Furthermore, the objectives of voters and parties with respect to the selection of candidates may differ, and are constrained by the career ambitions of individuals with political aspirations. But then, what really makes a career in the political sector different from a career in any other economic sector? There are at least three distinctive features that characterize the labor market in the political sector. First, politicians are typically under the spotlight, receiving the attention of the media and of a variety of citizens organizations. This makes politics a showcase, where politicians in office can display their political skills, while it might be more difficult for individuals working in the market sector to reveal their market ability. Second, inter-party competition for potential politicians is likely to be of secondary importance, as ideological preferences are more likely to attract individuals toward specific parties at the beginning of their political careers. Third, it is often the case that political parties take care of their losers by reserving partys positions to defeated incumbents. As a result, while individual careers within the political sector are inevitably linked to the opportunities available within parties, the extent to which individual endowments of political and market skills are correlated, or experience in the political (market) sector is also valuable in the market (political) sector, links the labor markets of the two sectors. This link affects the selection of politicians, the politicians careers, and the relationship between parties and voters.voters, parties, political sector

Two-dimensional Hybrid Simulations of Kinetic Plasma Turbulence: Current and Vorticity vs Proton Temperature

Proton temperature anisotropies between the directions parallel and perpendicular to the mean magnetic field are usually observed in the solar wind plasma. Here, we employ a high-resolution hybrid particle-in-cell simulation in order to investigate the relation between spatial properties of the proton temperature and the peaks in the current density and in the flow vorticity. Our results indicate that, although regions where the proton temperature is enhanced and temperature anisotropies are larger correspond approximately to regions where many thin current sheets form, no firm quantitative evidence supports the idea of a direct causality between the two phenomena. On the other hand, quite a clear correlation between the behavior of the proton temperature and the out-of-plane vorticity is obtained.Comment: 4 pages, 2 figures, Proceedings of the Fourteenth International Solar Wind Conferenc

Solar wind turbulence from MHD to sub-ion scales: high-resolution hybrid simulations

We present results from a high-resolution and large-scale hybrid (fluid electrons and particle-in-cell protons) two-dimensional numerical simulation of decaying turbulence. Two distinct spectral regions (separated by a smooth break at proton scales) develop with clear power-law scaling, each one occupying about a decade in wave numbers. The simulation results exhibit simultaneously several properties of the observed solar wind fluctuations: spectral indices of the magnetic, kinetic, and residual energy spectra in the magneto-hydrodynamic (MHD) inertial range along with a flattening of the electric field spectrum, an increase in magnetic compressibility, and a strong coupling of the cascade with the density and the parallel component of the magnetic fluctuations at sub-proton scales. Our findings support the interpretation that in the solar wind large-scale MHD fluctuations naturally evolve beyond proton scales into a turbulent regime that is governed by the generalized Ohm's law.Comment: 5 pages, 5 figures; introduction and conclusions changed, references updated, accepted for publication in ApJ

High-resolution hybrid simulations of kinetic plasma turbulence at proton scales

We investigate properties of plasma turbulence from magneto-hydrodynamic (MHD) to sub-ion scales by means of two-dimensional, high-resolution hybrid particle-in-cell simulations. We impose an initial ambient magnetic field, perpendicular to the simulation box, and we add a spectrum of large-scale magnetic and kinetic fluctuations, with energy equipartition and vanishing correlation. Once the turbulence is fully developed, we observe a MHD inertial range, where the spectra of the perpendicular magnetic field and the perpendicular proton bulk velocity fluctuations exhibit power-law scaling with spectral indices of -5/3 and -3/2, respectively. This behavior is extended over a full decade in wavevectors and is very stable in time. A transition is observed around proton scales. At sub-ion scales, both spectra steepen, with the former still following a power law with a spectral index of ~-3. A -2.8 slope is observed in the density and parallel magnetic fluctuations, highlighting the presence of compressive effects at kinetic scales. The spectrum of the perpendicular electric fluctuations follows that of the proton bulk velocity at MHD scales, and flattens at small scales. All these features, which we carefully tested against variations of many parameters, are in good agreement with solar wind observations. The turbulent cascade leads to on overall proton energization with similar heating rates in the parallel and perpendicular directions. While the parallel proton heating is found to be independent on the resistivity, the number of particles per cell and the resolution employed, the perpendicular proton temperature strongly depends on these parameters.Comment: 15 pages, 13 figures, submitted to Ap

Morse inequalities for the Koszul complex of multi-persistence

In this paper, we define the homological Morse numbers of a filtered cell complex in terms of the relative homology of nested filtration pieces and derive inequalities relating these numbers to the Betti tables of the multi-parameter persistence modules of the considered filtration. Using the Mayer-Vietoris spectral sequence we first obtain strong and weak Morse inequalities involving the above quantities, and then we improve the weak inequalities achieving a sharp lower bound for phonological Morse numbers. Furthermore, we prove a sharp upper bound for homological Morse numbers, expressed again in terms of the Betti tables

Multidimensional persistent homology is stable

Multidimensional persistence studies topological features of shapes by analyzing the lower level sets of vector-valued functions. The rank invariant completely determines the multidimensional analogue of persistent homology groups. We prove that multidimensional rank invariants are stable with respect to function perturbations. More precisely, we construct a distance between rank invariants such that small changes of the function imply only small changes of the rank invariant. This result can be obtained by assuming the function to be just continuous. Multidimensional stability opens the way to a stable shape comparison methodology based on multidimensional persistence.Comment: 14 pages, 3 figure