Showing papers by "Paris West University Nanterre La Défense published in 2016"

Interactions Between Risk Taking, Capital, and Reinsurance for Property–Liability Insurance Firms

Abstract: Financial theory has long recognized the structural relationship between capital and risk. This article posits reinsurance usage as a new endogenous decision variable and analyzes its effect on this decision mix from a sample of U.S. property–liability insurance firms. Empirical results obtained from a simultaneous equation model confirm the mutual interactions among capital, reinsurance and risk taking. Risk taking is positively related to capital, which highlights the effectiveness of regulatory mechanisms and the relevance of the capital buffer hypothesis. Reinsurance is negatively associated with capital, for which it displays a substitutive effect. These results seem to vary with the insurers’ level of capitalization, affiliation with a group, size, and organizational form. Unlike other decision variables, the capital ratio is adjusted to its target level.

Relaxation therapy and anxiety, self-esteem, and emotional regulation among adults with intellectual disabilities: A randomized controlled trial.

Abstract: This pilot study is a randomized controlled trial on the effects of relaxation on anxiety, self-esteem, and emotional regulation in adults with intellectual disabilities (ID) working in a center of supported employment in France. We studied 30 adults with mild or moderate ID who were split at random into a relaxation group (RG, 15 subjects), who completed 10 sessions of relaxation therapy, and a control group (CG, 15 subjects), who were on a waiting list. The method used is the pretest and posttest. Variables were assessed by the State-Trait Anxiety Inventory form Y scale, the Rosenberg Self-Esteem scale, and the Emotion Regulation Questionnaire. We found that in the RG, relaxation significantly reduced state anxiety, t(14, 15) = 17.8***, d = -0.72, and improved self-esteem, t(14, 15) = -7.7***, d = 1.03, and cognitive reappraisal, t(14, 15) = -6.3***, d = 1.3, while the CG showed no change for these variables. We conclude that relaxation seems to be an interesting therapeutic option for reducing anxiety in people with ID in a supported employment setting.

A Comparative Study Between the Wingate and Force–Velocity Anaerobic Cycling Tests: Effect of Physical Fitness

Abstract: Purpose: To verify the hypothesis that the peak power (PP) of a Wingate test (WT) is an underestimation of maximal power (Pmax) computed from the force–velocity test (FVT), to examine possible fatigue effect on Pmax, and to investigate the effect of load on mean power (MP) and fatigue index (FI) during a WT in trained and recreational men. Methods: Ten recreational (22.9 ± 1.7 y, 1.81 ± 0.06 m, 73.3 ± 10.4 kg) and 10 highly trained subjects (22.7 ± 1.4 y, 1.85 ± 0.05 m, 78.9 ± 6.6 kg) performed 2 WTs with 2 loads (8.7% and 11% of body mass [BM]) and an FVT on the same cycle ergometer, in randomized order. Results: Optimal load was equal to 10% BM in recreational participants. Given the quadratic relationship between load and power, the underestimation of Pmax was lower than 10% for the average values of trained and recreational participants with both loads. However, PP with a load equal to 8.7% BM was a large underestimation (~30%) of Pmax in the most powerful individuals. In addition, PP was not greater ...

Are Deep and Comprehensive Regional Trade Agreements Helping to Reduce Air Pollution

Abstract: This paper investigates whether membership in Regional Trade agreements (RTAs) with environmental provisions (EPs) affect relative and absolute levels of environmental quality and whether the inclusion of most comprehensive EPs is associated to higher environmental quality. In order to do so, the determinants of PM2.5 population weighted concentrations are estimated for a sample of OECD countries and OECD BRIICS over the period 1990 to 2011. The usual controls for scale, composition and technique effects are added to the estimated model and the endogeneity of income and trade variables is addressed using instruments. The main results indicate that membership in RTAs with EPs is in general associated with higher environmental quality in absolute terms, whereas no significant results are found for RTAs without EPs. Moreover, the concentration in emissions of the pairs of countries that belong to an RTA with EPs tends to converge for the country sample.

Construire l’alternative agro-alimentaire : Ressorts sociaux et politiques du déploiement des AMAP en Île-de-France Building an alternative agrifood system : A social and political cross-analysis within the Île-de-France region

Abstract: From 2000 to 2010, the production of organic vegetables in the Ile-de-France region grew principaly according to a community supported agriculture scheme, within the frame of a regional network called AMAP-IdF. This network unfolds through partnerships that transcends the boundaries historically established in the french agricultural fi eld and highlights the key role played by the territorialisation of public policies in the mutations currently at work in this fi eld . This case-study show that developing alternative agrifood systems remains problematic in an agricultural fi eld within which organisations created during the modernization era are still dominating. Meanwhile it illustrates how the penetration of the food fabric by urban dwellers helps expressing latent identity mutations within the agricultural social world itself. Mots cles : AMAP – agriculture biologique – peri-urbain – identites agricoles – politiques publiques – gouvernance, innovation

Coin Assaying and Commodity Money

Abstract: When money was made of gold and silver, individuals faced the problem of determining the intrinsic content of coins in many exchange situations. In this paper we look at a well-documented solution to this problem, and a key institution of the commodity money system: coin assaying. To that goal we build a model of search and matching in which agents trade using coins that are imperfectly recognizable, but have access to a coin inspection technology that reveals the intrinsic content of coins for a fee. We consider two sources of imperfect information: counterfeit coins and clipping. With counterfeits we show that coin assaying reduced the extent of inefficiencies associated with imperfect coins recognizability (namely lower traded quantities and lower trading frequencies). Yet it did not necessarily increase welfare because it unmasked counterfeits which then traded at a discount, reducing total output. With clipping, we show that agents clip for two reasons: in the hope of passing an inferior coin for a superior one, and to reduce the purchasing power of coins that are too valuable. While coin assaying could remove the first type of clipping, it had no effect on the second. While framed in the context of the commodity money system, our analysis relates to the more general issue of asset trading under imperfect information.

High-dynamic-range microscope imaging based on exposure bracketing in full-field optical coherence tomography.

Abstract: By applying the proposed high-dynamic-range (HDR) technique based on exposure bracketing, we demonstrate a meaningful reduction in the spatial noise in image frames acquired with a CCD camera so as to improve the fringe contrast in full-field optical coherence tomography (FF-OCT). This new signal processing method thus allows improved probing within transparent or semitransparent samples. The proposed method is demonstrated on 3 μm thick transparent polymer films of Mylar, which, due to their transparency, produce low contrast fringe patterns in white-light interference microscopy. High-resolution tomographic analysis is performed using the technique. After performing appropriate signal processing, resulting XZ sections are observed. Submicrometer-sized defects can be lost in the noise that is present in the CCD images. With the proposed method, we show that by increasing the signal-to-noise ratio of the images, submicrometer-sized defect structures can thus be detected.

Word‐to‐picture recognition is a function of motor components mappings at the stage of retrieval

Abstract: Embodied approaches of cognition argue that retrieval involves the re-enactment of both sensory and motor components of the desired remembering. In this study, we investigated the effect of motor action performed to produce the response in a recognition task when this action is compatible with the affordance of the objects that have to be recognised. In our experiment, participants were first asked to learn a list of words referring to graspable objects, and then told to make recognition judgements on pictures. The pictures represented objects where the graspable part was either pointing to the same or to the opposite side of the "Yes" response key. Results show a robust effect of compatibility between objects affordance and response hand. Moreover, this compatibility improves participants' ability of discrimination, suggesting that motor components are relevant cue for memory judgement at the stage of retrieval in a recognition task. More broadly, our data highlight that memory judgements are a function of motor components mappings at the stage of retrieval.

Experimental analysis of thermal and damage evolutions of DCFC under static and fatigue loading

Abstract: Discontinuous carbon fibre composite (DCFC) is a new low-cost material that has already been applied for commercial components, such as window frames of the Boeing 787 Dreamliner. Studying DCFC is very challenging because it does not show the same behaviour than conventional composites or isotropic materials. This work presents an experimental study of DCFC specimens submitted to static and fatigue tensile loading, based on mechanical and thermography non destructive evaluation (NDE) technique. An infra-red (IR) camera is used for real time monitoring of temperature change at the specimen outer surface. Under static loading, thermal response permits to well detect the early appearance of micro defects up to the final failure of DCFC material. Moreover, thermal response gives a good correlation with the damage evolution under fatigue loading. It is also shown that thermography method allows to successfully determine the high cycle fatigue strength (HCFS) of DCFC material. RÉSUMÉ. Les composites à fibres de carbone discontinues (DCFC) sont des matériaux relativement récents qui ont déjà été employés pour la fabrication de composants industriels, tels que par exemple les contours de hublots des Boeing 787 Dreamliner. Cependant leur utilisation pour la réalisation de pièces structurelles reste encore marginale, leurs lois de comportement s’avérant être assez différentes de celles mieux connues des composites à fibres longues. Cette étude présente donc les résultats expérimentaux obtenus sur des éprouvettes trouées en DCFC soumises à des sollicitations de traction, en quasi-statique et en fatigue. Les éprouvettes sont équipées de jauges d’extensométrie et chaque essai est suivi par caméra infra-rouge (IR) afin de relever les variations de température apparaissant en surface d’éprouvette. Les essais quasistatiques montrent que la caméra IR permet de relever, aussi bien de brèves variations de température localisées aléatoirement sur toute la surface de l’éprouvette dès les premiers niveaux Revue des composites et des matériaux avancés – n 2/2016, 165-184 166 RCMA. Volume 26 – n 2/2016 de chargements, quúne élévation de température progressive aux bords du trou à l’endroit où la rupture finale se produit. De plus, lors des essais de fatigue, il est montré qu’il existe une très bonne corrélation entre élévation de température et endommagement de l’éprouvette. Enfin, il est aussi montré que l’élévation de température de l’éprouvette est un paramètre qui permet de déterminer la limite de fatigue (HCFS) de ce matériau de manière beaucoup plus rapide que les méthodes traditionnellement employées.

Silver phiale said to be from al-Juba (al-Wusṭa Governorate) — an archaeological puzzle

Abstract: In March 2014, while recording finds in the Ministry of Heritage and Culture in al-Khuwair, artefacts unexpectedly came to light reportedly from al-Juba in Oman's Bar al-Ḥikmān, in al-Wusṭa Governorate, until recently an archaeologically little-researched part of the Sultanate. Some of the pieces could be attributed to the Samad LIA or perhaps the PIR, both from the centuries at the turning point of the ages from BCE to CE. Such finds have never before come to light in this part of Oman. Samad LIA sites are generally located some 220 km to the north on the southern flank of the al-Ḥajjar mountains in a zone c.160 x 105 km in area. Diagnostic pottery finds spread from Wadi Bānī Ruwāhah (UTM 40Q 620570 m E, 2561848 m N) eastwards to the coast, a smaller area than previously believed.

Learning from Survey Training Samples: Rate Bounds for Horvitz-Thompson Risk Minimizers

Abstract: The generalization ability of minimizers of the empirical risk in the context of binary classification has been investigated under a wide variety of complexity assumptions for the collection of classifiers over which optimization is performed. In contrast, the vast majority of the works dedicated to this issue stipulate that the training dataset used to compute the empirical risk functional is composed of i.i.d. observations. Beyond the cases where training data are drawn uniformly without replacement among a large i.i.d. sample or modelled as a realization of a weakly dependent sequence of r.v.'s, statistical guarantees when the data used to train a classifier are drawn by means of a more general sampling/survey scheme and exhibit a complex dependence structure have not been documented yet. It is the main purpose of this paper to show that the theory of empirical risk minimization can be extended to situations where statistical learning is based on survey samples and knowledge of the related inclusion probabilities. Precisely, we prove that minimizing a weighted version of the empirical risk, refered to as the Horvitz-Thompson risk (HT risk), over a class of controlled complexity lead to a rate for the excess risk of the order $O_{\mathbb{P}}((\kappa_N (\log N)/n)^{1/2})$ with $\kappa_N=(n/N)/\min_{i\leq N}\pi_i$, when data are sampled by means of a rejective scheme of (deterministic) size $n$ within a statistical population of cardinality $N\geq n$, a generalization of basic {\it sampling without replacement} with unequal probability weights $\pi_i>0$. Extension to other sampling schemes are then established by a coupling argument. Beyond theoretical results, numerical experiments are displayed in order to show the relevance of HT risk minimization and that ignoring the sampling scheme used to generate the training dataset may completely jeopardize the learning procedure.

Représentations sociales de la personne obèse et de l’obésité : effets de la situation de contact

Abstract: Resume Cet article presente une etude des representations sociales de la personne obese et de l’obesite. Deux cents femmes normo-ponderees, reparties en deux groupes (absence de contact vs presence de contact avec une personne obese) ont complete deux tâches d’associations verbales : l’une dans laquelle elles repondaient en leur nom propre (consigne standard) et l’autre dans laquelle elles repondaient a la place d’autres personnes (consigne de substitution). Les resultats issus des analyses factorielles des correspondances appuient l’hypothese de l’effet du contact intergroupe sur l’organisation des representations sociales explorees, puisque les participantes en contact avec des personnes obeses semblent avoir des representations plus empathiques que celles ne l’etant pas. En effet, lorsque les participantes ne s’expriment pas en leur nom propre, des representations contre-normatives sont produites. Ces resultats sont discutes au regard des theories du contact intergroupe et des representations sociales.

Insight et schizophrénie : revue de la littérature

Abstract: Resume Objectifs Ce travail consiste en une revue de la litterature mettant en evidence les differentes conceptions et les differentes modalites d’evaluation de l’insight des patients atteints de schizophrenie qui en decoulent. Il s’agit en effet de montrer que l’insight designe un phenomene possedant de multiples facettes et dimensions. Methode Les differentes conceptions et methodes d’evaluation de l’insight seront passees en revue afin de montrer la complexite du phenomene d’insight, la difficulte qu’il y a a evaluer de facon multidimensionnelle l’insight et a mettre en lien les dimensions specifiques (clinique, cognitif, processuel) qui sont impliquees dans l’evolution (favorable, defavorable) du trouble schizophrenique et de sa prise en charge. Resultats Cette revue de la litterature met en evidence la complexite de la notion d’insight dans le cadre de la schizophrenie. L’absence de consensus dans la definition de l’insight amene a penser l’insight dans la schizophrenie comme un phenomene complexe. L’une des consequences est alors la difficulte a l’evaluer de facon standardisee. Discussion Si la conscience de la maladie apparait comme un enjeu dans la prise en charge des patients, aucun consensus ne se degage dans les effets positifs ou deleteres qu’un bon degre d’insight pourrait avoir sur le patient, son trouble et sa prise en charge. Conclusion Afin de mieux comprendre les effets de l’insight, dans un travail en cours, des patients atteints de schizophrenie a des degres divers de remission seront interroges avec des outils multidimensionnels et un entretien standardise. L’objectif sera de confronter non seulement les points de vue (experts/patients) sur ce qu’est l’insight mais aussi de determiner de quelles facons les dimensions specifiques de l’insight pourraient etre importantes dans la prise en charge des patients atteints de schizophrenie.

Fractal Representation of Exergy

Abstract: We developed a geometrical model to represent the thermodynamic concepts of exergy and anergy. The model leads to multi-scale energy lines (correlons) that we characterised by fractal dimension and entropy analyses. A specific attention will be paid to overlapping points, rising interesting remarks about trans-scale dynamics of heat flows.

El derecho internacional humanitario en la jurisprudencia de la Corte Interamericana de Derechos Humanos

Abstract: The convergence of International Human Rights Law (IHRL) and International Humanitarian Law (IHL) can be seen in the jurisprudence of the Inter-American Court of Human Rights as of the year 2000. From that time, and until now, the Court has explicitly referred to IHL in its analysis of certain cases linked to situations of internal armed conflict. In that regard, the Court has been confronted by the need to verify that the facts of the relevant cases actually took place in such contexts and, moreover, has had to justify the reasons why its considerations refer to a legal framework that is external to the Inter-American corpus juris strictly speaking. The case law that has resulted from this practice demonstrates that the Inter-American Court has relied on IHL to complement the content and scope of human rights and of the general obligations of States in cases related to an internal armed conflict; and to integrate it to its reasoning, beyond mere interpretation, through references to the basic principles of ihl and to the consequences of a declaration of a State’s international responsibility. As such, the Inter-American Court, the regional organ par excellence for the monitoring of human rights, appears to have also become an indirect, perhaps even a direct, mechanism for the control of IHL.

Extension Sampling Designs for Big Networks: Application to Twitter

Abstract: With the rise of big data, more and more attention is paid to statistical network analysis. However, exact computation of many statistics of interest is of prohibitive cost for big graphs. Statistical estimators can thus be preferable. Model-based estimators for networks have some drawbacks. We study design-based estimates relying on sampling methods that were developed specifically for use on graph populations. In this contribution, we test some sampling designs that can be described as “extension” sampling designs. Unit selection happens in two phases: in the first phase, simple designs such as Bernoulli sampling are used, and in the second phase, some units are selected among those that are somehow linked to the units in the first-phase sample. We test these methods on Twitter data, because the size and structure of the Twitter graph is typical of big social networks for which such methods would be very useful.

Behavioural biology: Stones that could cause ripples.

Abstract: Monkeys have been observed pounding stones and unintentionally forming sharp-edged, tool-like fragments. This deliberate breakage raises questions about the evolution of intentional stone modification. See Letter p.85 In Brazil there are archaeological sites with abundant accumulations of chipped stones. The accumulation and the stones, if discovered in a three-million-year-old context in Africa, might be taken as evidence of an early stone tool culture. But in this instance the perpetrators have been caught in the act. This study reports observations of wild bearded capuchin monkeys (Sapajus libidinosus) deliberately breaking stones in Brazil's Serra da Capivara National Park. Why they do this is not clear, though they sometimes lick or sniff the crushed stone, prompting speculation that that they may be ingesting powdered quartz or lichens. However, the monkeys do not appear to use the sharp edges to cut or scrape other objects. These monkeys are the only non-hominin primates to interact with stone so frequently, and the fact that they produce accumulations of worked stone similar to those presumed elsewhere to represent the work of early hominins could help to inform interpretation of the human Palaeolithic record.

Spillover effects of global liquiditys expansion on emerging countries: evidences from a Panel VAR approach

Abstract: The attention for the global liquidity concept has grown over the recent years insofar as its dramatic increase is considered among regulators and economists as one of the possible determinants of the last global financial crisis. Although global liquidity remains without a generally accepted definition in the literature, the destabilizing effects of its expansion are widely studied, especially for the advanced economies. However, empirical studies regarding the consequences in the emerging countries are scarcer and this paper is related to this topic. We rely on a Panel VAR approach to investigate those effects on emerging economies and we find that the consequences are in line with the results of the literature on advanced countries. Nevertheless, contrary to previous empirical studies, we find that the choice of the exchange rate regimes is not important, as the exchange rate regime does not fully isolate the countries from a surge of global liquidity in the issuing countries.