References of "E-prints/Working papers"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSostanza e forma nella tradizione del romanzo arturiano in prosa
Leonardi, Lino; Morato, Nicola ULg

E-print/Working paper (in press)

Detailed reference viewed: 19 (1 ULg)
Full Text
See detailBien raisonner en TSUM (Transition Secondaire-Université en Mathématiques)
Bair, Jacques ULg

E-print/Working paper (2017)

Bien raisonner est assurément une des compétences clés que doivent acquérir et développer les étudiants entrant à l’Université. Nous y consacrons entièrement ce travail illustré par de nombreux exemples ... [more ▼]

Bien raisonner est assurément une des compétences clés que doivent acquérir et développer les étudiants entrant à l’Université. Nous y consacrons entièrement ce travail illustré par de nombreux exemples construits à partir de notre expérience professionnelle. En premier lieu, nous distinguons, à la suite de G. Polya, les raisonnements plausibles des raisonnements démonstratifs. Ensuite, nous nous intéressons à certains éléments de logique qui nous paraissent importants au niveau d’une TSUM. Puis, nous analysons la nature de preuves mathématiques à ce stade de l’apprentissage. Enfin, nous dissertons quelque peu sur l’usage des démonstrations dans l’enseignement. Ce travail se termine par deux annexes techniques, relatives respectivement à différents types de syllogismes et à quelques éléments plus formels de logique mathématique. [less ▲]

Detailed reference viewed: 25 (1 ULg)
Full Text
See detail"888" Tweets on the Art and Science of Internet-Based Investing
Choffray, Jean-Marie ULg

E-print/Working paper (2017)

Here we are! "888" Tweets on The Art and Science of Investing to “show you the way”, to share some observations on the evolution of the world, the behavior of the financial markets, and to illustrate the ... [more ▼]

Here we are! "888" Tweets on The Art and Science of Investing to “show you the way”, to share some observations on the evolution of the world, the behavior of the financial markets, and to illustrate the key heuristics that I learned over the last twenty years. As, without any doubt, I am no Warren Buffett, feel free to disagree and develop you own “theory” of investing. Painful and solitary work... Success is at that price! And, based on what I did - and did not! - achieve, it shouldn’t be hard to do much better... That’s my wish for you! [less ▲]

Detailed reference viewed: 334 (78 ULg)
Full Text
See detailMusic 4 A While - entretien avec deux des musiciens de ce projet
Sacré, Robert ULg

E-print/Working paper (2017)

Entretien avec Jean François Foliez ( clarinette) et Johan Dupont, pianiste, arrangeur et concepteur du projet Music 4 A While paru chez Igloo Records

Detailed reference viewed: 23 (0 ULg)
Full Text
See detailCorde à Corde - Le duo Philippe AERTS ( contrebasse) - Raphaëlle BROCHET (chant) - interview
Sacré, Robert ULg

E-print/Working paper (2017)

Interview des 2 musiciens sur leur carrière et sur la sortie de l'album KALAMAMBA chez Igloo Records ( IGL282)

Detailed reference viewed: 11 (1 ULg)
Full Text
See detailCreative Playground ( Jean François Foliez) - vidéo "Home" ( composition Johan Dupont)
Sacré, Robert ULg

E-print/Working paper (2017)

Spectacle "Creative Playground 2017" Théâtre de Liège, 4 mars 2017; en vidéo "Home" une composition du pianiste Johan Dupont

Detailed reference viewed: 18 (2 ULg)
Full Text
See detailChris BEARD - The Prince of the Blues
Sacré, Robert ULg

E-print/Working paper (2017)

Interview de Chris BEARD + record reviews

Detailed reference viewed: 20 (0 ULg)
Full Text
See detailLiens entre mathématiques et jeux
Bair, Jacques ULg

E-print/Working paper (2017)

Le présent travail se compose de plusieurs parties. En premier lieu, nous définissons le concept général de jeu et présentons quelques mathématiciens célèbres, de toutes époques, qui étaient (ou sont ... [more ▼]

Le présent travail se compose de plusieurs parties. En premier lieu, nous définissons le concept général de jeu et présentons quelques mathématiciens célèbres, de toutes époques, qui étaient (ou sont encore) des adeptes de jeux mathématiques. Ensuite, nous établissons une typologie des jeux mathématiques. Une deuxième partie est consacrée à l’intervention des jeux dans l’enseignement des mathématiques. Nous donnons divers avantages des activités ludiques en classe, mais également des objections relatives à leur usage à des fins pédagogiques. Nous nous demandons aussi comment sélectionner un jeu pour des élèves et exhibons des exemples concrets de jeux exploitables en classe. Ce travail se termine par une bibliographie sur le sujet, ainsi que par une annexe composée de diapositives présentées lors d’un exposé réalisé à l’Université du Luxembourg dans le cadre de la Formation Pédagogique (FOPED) : nous y décrivons brièvement différentes épreuves ludiques proposées ces dernières années à des élèves de l’enseignement secondaire en France, Belgique et au Luxembourg. [less ▲]

Detailed reference viewed: 27 (0 ULg)
Full Text
See detailMulti-period vehicle allocation with uncertain transportation requests
Crama, Yves ULg; Pironet, Thierry ULg

E-print/Working paper (2017)

This work investigates optimization techniques for a multi-period vehicle allocation problem with uncertain requests. A company owning a limited fleet of trucks attempts to maximize its operational profit ... [more ▼]

This work investigates optimization techniques for a multi-period vehicle allocation problem with uncertain requests. A company owning a limited fleet of trucks attempts to maximize its operational profit over an infinite horizon by optimally assigning transportation orders to the vehicles. Its profit stems from profits collected when transporting full truckloads, minus costs incurred when waiting or when moving unladen. The stochastic component of the problem arises from the uncertainty on the realization of each transportation order. The methodology is based on optimizing decisions for deterministic scenarios. Several policies are generated in this way, either by simple heuristics, or by more complex approaches, such as consensus and restricted expectation algorithms, or from network flow formulations over subtrees of scenarios. Myopic and a-posteriori deterministic optimization models are used to compute bounds allowing for performance evaluation. Numerical experiments are performed on various instances featuring different numbers of orders, graph sizes, sparsity, and probability distributions, and the performance of the algorithms is assessed by statistical tests. The robustness of various policies with respect to erroneous evaluations of the probability distributions is also analyzed. [less ▲]

Detailed reference viewed: 185 (16 ULg)
Full Text
See detailSur l'évaluation de compétences en mathématiques
Bair, Jacques ULg

E-print/Working paper (2017)

Ce document comprend deux parties. Tout d’abord, un texte est consacré à des généralités sur la mesure de compétences, ainsi qu’à la présentation, illustrée par des exemples concrets, de différents types ... [more ▼]

Ce document comprend deux parties. Tout d’abord, un texte est consacré à des généralités sur la mesure de compétences, ainsi qu’à la présentation, illustrée par des exemples concrets, de différents types d’échelles (universelle, descriptive, globale) et de grilles d’évaluation. Enfin, ce travail se termine par la reproduction de diapositives (initialement réalisées à l’aide du logiciel Power Point) préparées pour accompagner une leçon sur l’évaluation ; l’exposé oral correspondant a été donné, dans le cadre de la FOPED (Formation Pédagogique), à plusieurs cohortes de stagiaires en mathématiques à l’Université du Luxembourg. [less ▲]

Detailed reference viewed: 37 (1 ULg)
Full Text
Peer Reviewed
See detailTransparency Under Scrutiny. Information disclosure by the Parliamentary Land Investigation Commission in Myanmar
San Thein; Pyae Sone; Diepart, Jean-Christophe ULg

E-print/Working paper (2017)

This case study presents a country-wide quantitative analysis of a Parliamentary Commission established in 2012 in Myanmar to examine ‘land grab’ cases considered and to propose solutions towards ... [more ▼]

This case study presents a country-wide quantitative analysis of a Parliamentary Commission established in 2012 in Myanmar to examine ‘land grab’ cases considered and to propose solutions towards releasing the land to its original owners, in most cases smallholder farming families. The study analyses the information contained in four reports released to the public, but also aims to elicit information they do not reveal. First of all, the paper suggests the commission has failed to provide detailed information about land grabs by the military. Second, the Commission seems to have targeted urban areas and urbanization projects and has underestimated land grab cases in rural areas. Third, by contrasting the locations of land confiscation cases with those of agro-industrial concessions as of 2011, the paper also shows how the Commission has evaded, rather than tackled, some very critical land confiscation issues driven by these concessions. Eventually, the authors argue for a mechanism that gathers, manages and releases relevant data on land confiscation and redistribution in a manner that allows for full disclosure. [less ▲]

Detailed reference viewed: 22 (0 ULg)
Full Text
See detailPetite apologie de l'analogie en mathématiques
Bair, Jacques ULg

E-print/Working paper (2017)

L'analogie est souvent utilisée par les mathématiciens car elle s'avère déterminante très souvent dans la création de mathématiques nouvelles. Pour illustrer simplement ces propos, nous présentons deux ... [more ▼]

L'analogie est souvent utilisée par les mathématiciens car elle s'avère déterminante très souvent dans la création de mathématiques nouvelles. Pour illustrer simplement ces propos, nous présentons deux exemples, l'un de géométrie et l'autre d'analyse, qui ont été initialement développés par G. Polya. Une brève biographie de cet auteur est présentée en fin d'article. [less ▲]

Detailed reference viewed: 14 (1 ULg)
Full Text
Peer Reviewed
See detailIntegrated approach for ethics in research for young researchers at the University of Liege
Halleux, Isabelle ULg

E-print/Working paper (2017)

For ensuring good practices in research from the beginning and developing a culture of ethics, ULg developed an integrated approach focusing on young researchers. The objective is to instill, as soon as ... [more ▼]

For ensuring good practices in research from the beginning and developing a culture of ethics, ULg developed an integrated approach focusing on young researchers. The objective is to instill, as soon as possible, a good perception of what is quality in research, considering methodology, project management and ethics as norms and moral positioning for solving dilemma. Actions, coordinated by the Council for Ethics and Scientific Integrity (CEIS), are developed simultaneously through 5 axes. Young researchers are involved at all levels of the process, directly or as representative of the PhD Association. 1. Training: Sensitization and education to ethics; development of professional capacities, incl. data analysis & open data; seminaries with supervisors and PhDs ("duos") 2. Forum: ethics on the public space – Seminaries, conference, round tables, intervision, discussion and exchange on questions, dilemma, case-studies, with the help of external experts 3. Research appraisal: requirement for an ethics appraisal of each research project, with a special focus on human and social sciences, with the help of disciplinary ethics committees 4. Ethics analysis: Analysis of special questions, complains, problems, and decision making in case of violation of integrity 5. Regulation: Writing of procedures, dissemination of documents, recommendations and case-studies, link to the HR Strategy for researchers and the Charter and Code. In 2016, successful activities took place : - about 500 PhDs (25%) participated directly in the "Go2thesis training" (incl. 1 day on project management and ethics), dedicated trainings (introduction, special questions) and forum-debates - all the research projects, incl. PhD grants, supported by ULg were requested to provide an ethical issue check list, based on the H2020 standards. The R&D Office helped to explain about the issues and resources, and to orient the applicant to the ad hoc ethics committee - special requests were analyzed by the CEIS for several PhD's sensitive projects - Information was provided to PhDs regarding authorship, crowdfunding, privacy, open data and security while travelling New projects will be developed for (1) strengthening the relation between CEIS-ethics committee-doctoral school-supervisor-PhD (2) involving all the new PhDs in the training and forum, and (3) ensure the ethics appraisal during the whole duration of the PhD thesis (i.e. special chapter in the annual report). This presentation aims to exchange about what was done, the actual and expected impact of actions, what is going right and wrong, and how ULg is managing this dynamics as part of the HR Strategy for researchers project. A discussion with participants is expected on results and new projects. [less ▲]

Detailed reference viewed: 30 (4 ULg)
Full Text
See detailQuelques idées générales à propos de la compréhension en mathématiques
Bair, Jacques ULg

E-print/Working paper (2017)

Dans cet article, nous apportons des éléments de réponse à la question générale suivante : "Que signifie bien comprendre en mathématiques ?" Nous nous demandons pourquoi il est difficile d'y répondre et ... [more ▼]

Dans cet article, nous apportons des éléments de réponse à la question générale suivante : "Que signifie bien comprendre en mathématiques ?" Nous nous demandons pourquoi il est difficile d'y répondre et apportons une piste de solution en distinguant les activités de production de celles de reproduction. De plus, nous abordons le problème étudié d'un point de vue aussi bien local que global. Enfin, nous nous interrogeons sur l'incompréhension en mathématiques en proposant une typologie, en repérant des causes possibles d'incompréhension et en donnant quelques conseils pratiques. [less ▲]

Detailed reference viewed: 31 (4 ULg)
Full Text
See detailDecidable properties of extension graphs for substitutive languages
Dolce, Francesco; Kyriakoglou, Revekka; Leroy, Julien ULg

E-print/Working paper (2017)

Detailed reference viewed: 8 (0 ULg)
Full Text
See detailDivergence of wavelet series: A multifractal analysis
Esser, Céline ULg; Jaffard, Stéphane ULg

E-print/Working paper (2017)

We show the relevance of a multifractal-type analysis for pointwise convergence and divergence properties of wavelet series: Depending on the sequence space which the wavelet coefficients sequence belongs ... [more ▼]

We show the relevance of a multifractal-type analysis for pointwise convergence and divergence properties of wavelet series: Depending on the sequence space which the wavelet coefficients sequence belongs to, we obtain deterministic upper bounds for the Hausdorff dimensions of the sets of points where a given rate of divergence occurs, and we show that these bounds are generically optimal, according to several notions of genericity. [less ▲]

Detailed reference viewed: 11 (1 ULg)
Full Text
Peer Reviewed
See detailBack to materialism Reflections on Marx’s labour, praxis, cooperative and libertarian socialism in the 19th century
Frère, Bruno ULg

E-print/Working paper (2017)

From Marx to Althusser, the materialist approach has tended to assume that individuals (that is, workers, proletarians and other social actors), unconsciously reproduce the social structures of capitalism ... [more ▼]

From Marx to Althusser, the materialist approach has tended to assume that individuals (that is, workers, proletarians and other social actors), unconsciously reproduce the social structures of capitalism which alienate them. It is assumed that individuals accept the conditions forced upon them and no longer seek to rebel against a world which substantially impoverishes their labour, their spirit and their creativity. In this paper, I will try to show that by dint of favouring almost exclusively Marx's concept of alienation, there is a considerable risk that materialist thought will adopt only a negative path. Whilst I acknowledge Marx’s significance to materialism, I wish to argue that his stance should be combined with that of the anarchist and libertarian French thinker Proudhon. Proudhon has succeeded in presenting a conception of the worker as more than just alienated. Workers can also cooperate and experience a reciprocity seemingly at odds with the character of capitalism. Under Proudhon’s influence materialism takes a positive turn, enabling us to avoid falling into the utopianism that the theory of social economy employs to critique capitalism – a utopianism that renders its critique even less effective than that of Marx. [less ▲]

Detailed reference viewed: 61 (1 ULg)
Full Text
Peer Reviewed
See detailHow to account for new forms of resistance to domination: An argument for a materialist renewal in European social theory
Frère, Bruno ULg; Tulle, Emmanuelle

E-print/Working paper (2017)

Many significant intellectual developments have taken place in 20th century European social theories. Notably the first Frankfurt School and Bourdieu’s work have successfully shown how workers, social ... [more ▼]

Many significant intellectual developments have taken place in 20th century European social theories. Notably the first Frankfurt School and Bourdieu’s work have successfully shown how workers, social actors, etc. are alienated or dominated by capitalist social structures. But according to Habermas, neither perspective successfully allows for the possibility that people could contribute to their own emancipation. The emergence of new forms of social resistance to domination such as those embodied by the Indignados, Anonymous, Femen, the practitioners of alternative economy, movements of unemployed people or illegals compels us to envisage the possibility for emancipation, but how? In this paper we explore opportunities for accounting for this by considering the work of a range of other European social theorists, more specifically Boltanski whose critical intent is embodied in his pragmatic sociology, and evident in his coining and use of the concept of the world. In addition we will consider Latour’s own pragmatic stance as we believe that despite his disinterest in new social movements, his work, informed by pure immanence, might offer potential solutions. But we would argue that even in these innovations there is either a persistent tendency to imagine emancipation primarily as a return to some ideal state or a lack of critical engagement with alienation. In response, we propose a materialist renewal, which will lead us to ponder on the political role of sociologists. [less ▲]

Detailed reference viewed: 59 (2 ULg)
Full Text
See detailA tailored two-phase constructive heuristic for the three-dimensional Multiple Bin Size Bin Packing Problem with transportation constraints
Paquay, Célia ULg; Limbourg, Sabine ULg; Schyns, Michael ULg

E-print/Working paper (2017)

This paper considers the three-dimensional Multiple Bin Size Bin Packing Problem which consists in packing a set of cuboid boxes into containers of various shapes with minimising unused space. The problem ... [more ▼]

This paper considers the three-dimensional Multiple Bin Size Bin Packing Problem which consists in packing a set of cuboid boxes into containers of various shapes with minimising unused space. The problem is extended to air cargo where bins are Unit Load Devices, especially designed for fitting in aircraft. We developed a fast constructive heuristic able to manage the different constraints met in transportation. The heuristic is split into two distinct phases. The first phase deals with the packing of boxes into identical bins using an extension of the Extreme Points. During this phase, the fragility, stability and orientations of the boxes are taken into account as well as the special shape of the bins and their weight capacity. The second phase takes into account the multiple types of available bins. If necessary, the best found loading pattern is finally enhanced with respect to weight distribution in a post processing. After parametrisation, computational experiments have been performed on data sets especially designed for this application. The heuristic requires really short computational times to achieve promising results. [less ▲]

Detailed reference viewed: 15 (0 ULg)
Peer Reviewed
See detailAn intermediary's geographical expansion choice under uncertainty
Lefevre, Mélanie ULg; Tharakan, Joseph ULg

E-print/Working paper (2017)

Detailed reference viewed: 30 (1 ULg)
Full Text
See detail"On se débrouille". How to be a good judge when the state lets you down
Andreetta, Sophie ULg; Kolloch, Annalena

E-print/Working paper (2017)

Over the last couple of years, Beninese magistrates have gone on multiple strikes. Most of them complain about their substantial workload, low pay, and poor working conditions. They also highlight the ... [more ▼]

Over the last couple of years, Beninese magistrates have gone on multiple strikes. Most of them complain about their substantial workload, low pay, and poor working conditions. They also highlight the discrepancies between the magistrates’ social status and what their families expect from them. While there seems to be a professional malaise within the Beninese bench, judges and prosecutors also insist on the importance of their work and the ethics that goes together with it. This is why we will be looking at the discourses and representations of the social and professional status of Beninese judges. Why do young lawyers choose the path of being a magistrate over other legal careers? How do judges and prosecutors in the Republic of Benin balance professional ethos with practical work routine? [less ▲]

Detailed reference viewed: 40 (3 ULg)
Full Text
See detailExtracting oscillating components from nonstationary time series: A wavelet-induced method
Deliège, Adrien ULg

E-print/Working paper (2017)

This paper consists in the description and application of a new method named Wavelet-Induced Mode Extraction (WIME) in the context of time-frequency analysis. WIME aims to extract the oscillating ... [more ▼]

This paper consists in the description and application of a new method named Wavelet-Induced Mode Extraction (WIME) in the context of time-frequency analysis. WIME aims to extract the oscillating components that build amplitude modulated-frequency modulated signals. The essence of this technique relies on the successive extractions of the dominant ridges of wavelet-based timefrequency representations of the signal under consideration. Our tests on simulated examples indicate strong decomposition and reconstruction skills, trouble-free handling of crossing trajectories in the time-frequency plane, sharp performances in frequency detection in the case of mode-mixing problems and a natural tolerance to noise. These results are compared with those obtained with the Empirical Mode Decomposition. We also show that WIME still gives meaningful results with real-life data, namely the Oceanic Niño Index. [less ▲]

Detailed reference viewed: 29 (16 ULg)
Full Text
See detailStudy Protocol: Effect of prenatal wheel-running exercise (before and during gestation) on cocaine psychomotor sensitization expressed in the offspring in periadolescent females and males C57BL/6J mice
Lespine, Louis-Ferdinand ULg; Plenevaux, Alain ULg; Tirelli, Ezio ULg

E-print/Working paper (2017)

The present study principally aims at determining to which extent prenatal exercise (before and during gestation) could affect the initiation (establishment) and the expression of psychomotor ... [more ▼]

The present study principally aims at determining to which extent prenatal exercise (before and during gestation) could affect the initiation (establishment) and the expression of psychomotor sensitization induced by a representative dose of cocaine in young female and male mice. More specifically, we will assess cocaine-induced acute psychomotor-activating effects, psychomotor sensitization developing over 9 daily sessions (daily peritoneal injections of cocaine or saline) and the long-term expression of the sensitized response (30 days after the last sensitizing injection) in C57BL/6J mice born from mothers housed with or without a running wheel before and during gestation. Based on literature and on our prior results, the mice born from exercised mothers are expected to show significantly reduced levels of cocaine responsiveness in comparison with the control mice (born from unexercised mothers). [less ▲]

Detailed reference viewed: 31 (5 ULg)
Full Text
See detailIntroduction
Masson, Christophe ULg

E-print/Working paper (2017)

Introduction de l'Assemblée générale de Ménestrel – 35e journée d'étude du Réseau des Médiévistes belges de Langue française. Le Moyen Âge dans les (nouveaux) médias. Quelle place pour les médiévistes  ... [more ▼]

Introduction de l'Assemblée générale de Ménestrel – 35e journée d'étude du Réseau des Médiévistes belges de Langue française. Le Moyen Âge dans les (nouveaux) médias. Quelle place pour les médiévistes ? Université de Liège, 7-8 octobre 2016 [less ▲]

Detailed reference viewed: 12 (0 ULg)
Full Text
See detailBerge-acyclic multilinear 0-1 optimization problems
Buchheim, Christoph; Crama, Yves ULg; Rodriguez Heck, Elisabeth ULg

E-print/Working paper (2016)

Detailed reference viewed: 34 (4 ULg)
Peer Reviewed
See detailVorzeitigkeit als Herausforderung beim Übersetzen narrativer Texte
Münzberg, Franziska ULg

E-print/Working paper (2016)

Detailed reference viewed: 14 (0 ULg)
Full Text
See detailCellwise Robust regularized discriminant analysis
Aerts, Stéphanie ULg; Wilms, Ines

E-print/Working paper (2016)

Quadratic and Linear Discriminant Analysis (QDA/LDA) are the most often applied classification rules under normality. In QDA, a separate covariance matrix is estimated for each group. If there are more ... [more ▼]

Quadratic and Linear Discriminant Analysis (QDA/LDA) are the most often applied classification rules under normality. In QDA, a separate covariance matrix is estimated for each group. If there are more variables than observations in the groups, the usual estimates are singular and cannot be used anymore. Assuming homoscedasticity, as in LDA, reduces the number of parameters to estimate. This rather strong assumption is however rarely verified in practice. Regularized discriminant techniques that are computable in high-dimension and cover the path between the two extremes QDA and LDA have been proposed in the literature. However, these procedures rely on sample covariance matrices. As such, they become inappropriate in presence of cellwise outliers, a type of outliers that is very likely to occur in high-dimensional datasets. In this paper, we propose cellwise robust counterparts of these regularized discriminant techniques by inserting cellwise robust covariance matrices. Our methodology results in a family of discriminant methods that (i) are robust against outlying cells, (ii) cover the gap between LDA and QDA and (iii) are computable in high-dimension. The good performance of the new methods is illustrated through simulated and real data examples. As a by-product, visual tools are provided for the detection of outliers. [less ▲]

Detailed reference viewed: 22 (1 ULg)
Full Text
See detailPotential, opportunities and benefits of electric vehicles as frequency regulation resources
Glavic, Mevludin ULg; Alvarado, Fernando

E-print/Working paper (2016)

Any imbalance between electric power supply and demand results in power system frequency deviations from its nominal value. Frequency regulation is one of the most important services that regional system ... [more ▼]

Any imbalance between electric power supply and demand results in power system frequency deviations from its nominal value. Frequency regulation is one of the most important services that regional system operators perform to ensure reliable system operation. Traditional power supply sources such as generators are usually automatically modulated to help balance generation and demand by adjusting their output based in part on system frequency. As a result of the decreased inertia of the system caused by decommissioning of traditional power plants and the increase in the penetration of renewable energy sources, the increased use of demand side controls for the purpose of frequency regulation is receiving increased attention. Demand control can provide fast response to any imbalance. This opens up the possibility for Electric Vehicles (EVs) to be used as frequency regulation grid resources. This write-up discusses the potential, opportunities and benefit of doing so. [less ▲]

Detailed reference viewed: 41 (1 ULg)
Full Text
See detailPREDetector 2.0: Online and Enhanced Version of the Prokaryotic Regulatory Elements Detector Tool
Tocquin, Pierre ULg; Naomé, Aymeric ULg; Jourdan, Samuel ULg et al

E-print/Working paper (2016)

In the era that huge numbers of microbial genomes are being released in the databases, it becomes increasingly important to rapidly mine genes as well as predict the regulatory networks that control their ... [more ▼]

In the era that huge numbers of microbial genomes are being released in the databases, it becomes increasingly important to rapidly mine genes as well as predict the regulatory networks that control their expression. To this end, we have developed an improved and online version of the PREDetector software aimed at identifying putative transcription factor-binding sites (TFBS) in bacterial genomes. The original philosophy of PREDetector 1.0 is maintained, i.e. to allow users to freely fix the DNA-motif screening parameters, and to provide a statistical means to estimate the reliability of the prediction output. This new version offers an interactive table as well as graphics to dynamically alter the main screening parameters with automatic update of the list of identified putative TFBS. PREDetector 2.0 also has the following additional options: (i) access to genome sequences from different databases, (ii) access to weight matrices from public repositories, (iii) visualization of the predicted hits in their genomic context, (iv) grouping of hits identified in the same upstream region, (v) possibility to store the performed jobs, and (vi) automated export of the results in various formats. PREDetector 2.0 is available at http://predetector.fsc.ulg.ac.be/. [less ▲]

Detailed reference viewed: 29 (4 ULg)
Full Text
See detailStatus and Coordination in Organizations
Lam, Wing Man Wynne ULg

E-print/Working paper (2016)

Detailed reference viewed: 34 (5 ULg)
Full Text
See detailRapport 2016 sur l'égalité femmes/hommes à l'Université de Liège
Cornet, Annie ULg; Hakizumukama, Alexis ULg

E-print/Working paper (2016)

Detailed reference viewed: 18 (0 ULg)
Peer Reviewed
See detailMerger incentives under yardstick competition: A theoretical model
Teusch, Jonas ULg

E-print/Working paper (2016)

Detailed reference viewed: 13 (1 ULg)
Full Text
Peer Reviewed
See detailThe smallholder development by remittances of migrants
Yao Namé, Juste Michel ULg; Lebailly, Philippe ULg

E-print/Working paper (2016)

The following pages report the results of our survey conducted among (Malian, Senegalese and Mauritanian) Soninké migrants during the period of 14th to 4 December 2015, living in the social residences of ... [more ▼]

The following pages report the results of our survey conducted among (Malian, Senegalese and Mauritanian) Soninké migrants during the period of 14th to 4 December 2015, living in the social residences of the former home Pinel (first home of migrant workers in France). This survey had to aim to discuss the implementation and use of a new tool to transfer the money in order to reduce use of informal channels, to promote financial inclusion, to finance smallholding and to develop entrepreneurship in rural by granting of credits medium or long term via Microfinance Institutions (IMF). [less ▲]

Detailed reference viewed: 22 (11 ULg)
Full Text
See detailLE COMPROMIS ENTRE CULTURE NON PUNITIVE ET CULTURE JUSTE : ANALYSE DES SOUS-CULTURES DE SÉCURITÉ DES PATIENTS DANS UN SERVICE DE RADIOTHÉRAPIE
Kamto Kenmogne, Marius ULg; Van Caillie, Didier ULg; BOGA, Deniz ULg et al

E-print/Working paper (2016)

The recent publication of the report "Medical error-the third leading causes of death in the US" (Makary & Daniel, 2016) has led to a renewed attention to the issue of patient safety in many developed ... [more ▼]

The recent publication of the report "Medical error-the third leading causes of death in the US" (Makary & Daniel, 2016) has led to a renewed attention to the issue of patient safety in many developed countries. The main issue involved is the role played by medical staff work in the occurrence of deaths from the medical care. According to Makary & Daniel, communication failures, misdiagnosis, bad judgments and inadequate skills have caused an average of 251,454 deaths per year in the United States in 2013. This report has taken the opposite view of the proponents of "No shame no blame" approach characterizing a non-punitive culture in which people are led to blame the system even though human responsibility is obvious. While the no-blame culture has often been presented as the success factor of an efficient safety /quality policy in medical settings (Amalberti et al., 2005; Woynar et al, 2007), discordant voices now stand to underline the limits of this approach (see eg Dekker & Breakey, 2016; Levitt, 2014 or Shojania & Dixon-Woods, 2013). These authors argue that the no-blame culture is difficult to implement in practice and suggest the implementation of a just culture that places more emphasis on individuals' behavior and performance and on their responsibility at work. In this context, this study examines – based on an in-depth longitudinal case study of a radiotherapy department that has implemented a reporting system for adverse events - the extent to which non-punitive culture and just culture can live together in the same organizational unit. By combining in-depth interviews with members of the quality team and a questionnaire survey administered to all staff, we evaluate the current safety subcultures in the service. The content analysis of the interviews and the treatment of questionnaires following the methodology of the Agency for Healthcare Research and Quality allows to see the emergence of three subcultures in the radiotherapy department studied: a reporting subculture, a non-punitive subculture and, to some extent, a just subculture. The study shows that the development of the safety culture in this department is based primarily on the establishment of a non-punitive subculture used as a way to encourage spontaneous reporting of adverse events. The reporting culture is therefore the more controlled dimension of the safety culture of the department. Concerning responsibility of workers, the study shows that they have no fear of punishment and are not even familiar with the term in the workplace. On the contrary, instead of a retributive just culture, the department has focused its safety culture on learning from mistakes and substantial just culture based on a system of worker participation in the preparation of procedures that prescribe the right way to work. [less ▲]

Detailed reference viewed: 18 (3 ULg)
Full Text
See detailLa Cour pénale internationale et les entorses aux droits essentiels des personnes privées de liberté
Deprez, Christophe ULg

E-print/Working paper (2016)

Ce texte propose un bref aperçu des faiblesses de la pratique de la Cour pénale internationale en matière de privation de liberté.

Detailed reference viewed: 17 (0 ULg)
See detailIT formulae for gamma target: mutual information and relative entropy
Arras, Benjamin ULg; Swan, Yvik ULg

E-print/Working paper (2016)

Detailed reference viewed: 12 (1 ULg)
Full Text
Peer Reviewed
See detailLARCH: A package for estimating multinomial, nested, and cross-nested logit models that account for semi-aggregate data
Newman, Jeffrey; Lurkin, Virginie ULg; Garrow, Laurie

E-print/Working paper (2016)

We present a summary of important computational issues and opportunities that arise from the use of semi-aggregate data (where the explanatory data for choice scenarios are not necessarily unique for each ... [more ▼]

We present a summary of important computational issues and opportunities that arise from the use of semi-aggregate data (where the explanatory data for choice scenarios are not necessarily unique for each decision-maker) in discrete choice models. This data feature is commonly encountered with large transactional databases that have limited consumer information, such as itinerary choice modeling. We developed a software package called Larch, written in Python and C++, to take advantage of this kind of data to greatly speed the estimation of discrete choice model parameters. Benchmarking experiments against Stata (a commonly used commercial package) and Biogeme (a commonly used freeware package) based on an industry dataset for airline itinerary choice modeling applications shows that the size of the input estimation files are 50 to 100 times larger in Stata and Biogeme, respectively. Estimation times are also much faster in Larch; e.g., for a small itinerary choice problem, a multinomial logit model estimated in Larch converged in less than one second whereas the same model took almost 15 seconds in Stata and more than three minutes in Biogeme. For more complex discrete choice models, such as the ordered generalized extreme value model, estimation times were two seconds in Larch and four to five days in Biogeme. [less ▲]

Detailed reference viewed: 95 (4 ULg)
Full Text
See detailTHE BEAT GENERATION Beat Generation - L’Anthologie Musicale - Hep Cats, Hipsters & Beatniks 1936-1962 (FREMEAUX & ASSOCIES)
Sacré, Robert ULg

E-print/Working paper (2016)

The Beat Generation - L’Anthologie Musicale - Compte rendu Hep Cats, Hipsters & Beatniks 1936-1962 FREMEAUX & ASSOCIES

Detailed reference viewed: 27 (1 ULg)
Full Text
See detailBIG NOISE - Un orchestre belge- Un nouvel hommage, en live, au JAZZ style NEW ORLEANS
Sacré, Robert ULg

E-print/Working paper (2016)

Compte Rendu du 3è opus du groupe BIG NOISE, un orchestre belge qui remet à l'honneur le jazz traditionnel style NEW ORLEANS ( album IGLOO RECORDS)

Detailed reference viewed: 9 (1 ULg)
Full Text
Peer Reviewed
See detailThe np- Control Charts with the Guaranteed In-Control Performance
Faraz, Alireza ULg; Heuchenne, Cédric ULg

E-print/Working paper (2016)

In this paper, we evaluate the in-control performance of np-control charts with estimated parameters. We then apply the bootstrap method to adjust the control charts’ limits to guarantee the desired in ... [more ▼]

In this paper, we evaluate the in-control performance of np-control charts with estimated parameters. We then apply the bootstrap method to adjust the control charts’ limits to guarantee the desired in-control average run length (ARL0) value in monitoring stage. The adjusted limits ensure that ARL0 would take a value greater than the desired value (say, B) with a certain specified probability, that is Pr⁡(ARL_0>B)=1-ρ. We finally provide users with tables which with practitioners do not need to do bootstrapping Phase I data set to obtain the control limit thresholds. [less ▲]

Detailed reference viewed: 110 (1 ULg)
Full Text
See detailWASP-86b and WASP-102b: super-dense versus bloated planets
Faedi, F.; Gómez Maqueo Chew, Y.; Pollacco, D. et al

E-print/Working paper (2016)

We report the discovery of two transiting planetary systems: a super dense, sub-Jupiter mass planet WASP-86b (\mpl\ = 0.82 $\pm$ 0.06 \mj, \rpl\ = 0.63 $\pm$ 0.01 \rj), and a bloated, Saturn-like planet ... [more ▼]

We report the discovery of two transiting planetary systems: a super dense, sub-Jupiter mass planet WASP-86b (\mpl\ = 0.82 $\pm$ 0.06 \mj, \rpl\ = 0.63 $\pm$ 0.01 \rj), and a bloated, Saturn-like planet WASP-102b (\mpl\ = 0.62 $\pm$ 0.04 \mj, \rpl\=1.27 $\pm$ 0.03 \rj). They orbit their host star every $\sim$5.03, and $\sim$2.71 days, respectively. The planet hosting WASP-86 is a F7 star (\teff\ = 6330$\pm$110 K, \feh\ = $+$0.23 $\pm$ 0.14 dex, and age $\sim$0.8--1~Gyr), WASP-102 is a G0 star (\teff\ = 5940$\pm$140 K, \feh\ = $-$0.09$\pm$ 0.19 dex, and age $\sim$1~Gyr). These two systems highlight the diversity of planetary radii over similar masses for giant planets with masses between Saturn and Jupiter. WASP-102b shows a larger than model-predicted radius, indicating that the planet is receiving a strong incident flux which contributes to the inflation of its radius. On the other hand, with a density of $\rho_{pl}$ = 3.24$\pm$~0.3~$\rho_{jup}$, WASP-86b is the densest gas giant planet among planets with masses in the range 0.05 $<M$_{pl}$<$ 2.0 \mj. With a stellar mass of 1.34 M$_{\odot}$ and \feh = $+$0.23 dex, WASP-86 could host additional massive and dense planets given that its protoplanetary disc is expected to also have been enriched with heavy elements. In order to match WASP-86b's density, an extrapolation of theoretical models predicts a planet composition of more than 80\% in heavy elements (whether confined in a core or mixed in the envelope). This fraction corresponds to a core mass of approximately 210\me\ for WASP-86b's mass of \mpl$\sim$260\,\me. Only planets with masses larger than about 2\mj\ have larger densities than that of WASP-86b, making it exceptional in its mass range. [less ▲]

Detailed reference viewed: 9 (1 ULg)
Full Text
See detailThe Economic Forces Behind Deindustrialization: An Empirical Investigation
Van Neuss, Leif ULg

E-print/Working paper (2016)

The purpose of this paper is to provide an in-depth study of deindustrialization and to systematically analyze the reasons why the world’s most economically successful countries have experienced a sharp ... [more ▼]

The purpose of this paper is to provide an in-depth study of deindustrialization and to systematically analyze the reasons why the world’s most economically successful countries have experienced a sharp decline in relative manufacturing employment over the last decades. A large strand of empirical literature on deindustrialization aims at quantifying the relative importance of the economic forces behind deindustrialization, especially of the ‘internal’ and ‘external’ factors. While this study does not contradict the widespread belief that internal factors are quantitatively more important in explaining deindustrialization in advanced countries taken as a whole, our results, based on both static and dynamic techniques and panel data on 18 OECD countries from 1977 to 2007, however suggest that the role of globalization may be revised upwards when resorting to appropriate and well-defined indicators of trade in manufactures. [less ▲]

Detailed reference viewed: 31 (0 ULg)
Full Text
Peer Reviewed
See detailThey will need land! The current land tenure situation and future land allocation needs of smallholder farmers in Cambodia
Diepart, Jean-Christophe ULg

E-print/Working paper (2016)

The objective of this background paper is to provide a succinct description of the land tenure situation in Cambodia and, on that basis, discuss the needs smallholder farmers have for land, projected up ... [more ▼]

The objective of this background paper is to provide a succinct description of the land tenure situation in Cambodia and, on that basis, discuss the needs smallholder farmers have for land, projected up to the year 2030. The main problem it examines lies at the intersection between, on one hand, the demographic increase in the rural smallholder population and its associated need for land in the future (the demand side) and, on the other hand, the possibility offered by the different land tenure regimes to meet this demand (the supply side); the central question focuses on how supply can meet demand.By looking first at how much land is available under different categories (the supply side), the paper succinctly presents and maps the different land tenure regimes with updated statistics and discusses their main outcomes and shortcomings. On that basis, we present a preliminary assessment of land distribution by main land tenure systems in Cambodia. The land under cultivation by smallholders represents 19 percent of the total area of the national territory and is itself sub-divided into agricultural land with land titles (systematic land registration, 6 percent and land covered by the Order 01, 6 percent), under Social Land Concession arrangements (1 percent) and untitled (6 percent). The forest cover includes forest concessions (10 percent), Community Forestry (2 percent), Protected Areas and Protection Forests (20 percent) and an unclassified forest cover area (14 percent). Economic Land Concessions under operation represent 12 percent while cancelled concessions represent 2 percent of the total territory. The actual tenure of a large non-forested area (14 percent) remains undetermined and further updates are needed to shed light on this issue. The paper suggests that the central problem of the current Cambodian land reform is its ineffectiveness in coordinating the processes of land rights security and formalization in lowland and upland areas, although both regions are closely linked through land-driven migration movements that have intensified over the past 20 years. This has been particularly contentious given the fact that in a parallel process, and driven by a strong, state-based political economy, large land deals have been concentrated in the uplands of the entire country along processes that are exclusionary in nature. The overlap of competing land claims has created a widespread conflict situation in all uplands region of the country. By looking at how much land is needed for family farmers in the future (the demand side), the paper anticipates the land requirements of smallholder farmers by 2030 based on the projected demographic increase in the economically active population in rural Cambodia and on two sets of scenarios i) the transfer of unskilled labour from the agricultural to the secondary and tertiary sectors (industries and services) and ii) the provision of land for smallholder farmers. The analysis suggests that by the year 2030, the transfer of unskilled labour from agriculture to the secondary and tertiary sectors will lag behind the demographic increase in the active rural population. With 2015 as a baseline, the scenarios suggests that by 2030 smallholder farmers will need an additional land area ranging from 320,600 ha (+10 percent in relation to the actual area at the present time) to 1,962,400 (+64 percent), with an average desirable scenario of 1,622.000 ha based on an allocation of 1ha per active labourer (in accordance with the present social concession policy) and on the continuation of the present transfer rate of unskilled manpower from agriculture to the secondary and tertiary sectors (i.e. the transfer of 40.000 workers per year). So the question that needs to be formulated does not revolve around whether or not the rural population will need land in the future, but rather around how this can occur. Along these lines, the paper discusses different options, which are not mutually exclusive, to allocate this land without further impact on the forest cover: i) by redistribution of land from cancelled Economic Land Concessions, ii) through a firmer recognition of swidden agriculture inside Protected Areas, iii) through a far more ambitious Social Land Concession programme and iv) through further reform of the forest concession system. The paper concludes by stressing the need for relevant ministries to engage in open and constructive research-based discussion so that these options can materialize into concrete actions. [less ▲]

Detailed reference viewed: 62 (2 ULg)
Peer Reviewed
See detailThymectomy in myasthenia gravis: removal of the defective 'sick' organ?
Geenen, Vincent ULg

E-print/Working paper (2016)

As evidenced by this randomized trial, thymectomy clearly improved clinical status of patients with nonthymomatous myasthenia gravis (MG) and this study ends a very long controversy about the interest of ... [more ▼]

As evidenced by this randomized trial, thymectomy clearly improved clinical status of patients with nonthymomatous myasthenia gravis (MG) and this study ends a very long controversy about the interest of this surgical procedure mainly based on previous empirical observations. Although they are not discussed in this important paper, a series of experimental arguments reviewed in joint references argue for the idea that the clinical benefit of thymectomy is primarily due to the removal of the organ primarily implicated in MG pathophysiology. The thymus plays a central role in programming central immunological self-tolerance [1,2], and a thymus dysfunction is a primary event in the development of organ-specific autoimmunity [3,4]. It is therefore not surprising that the surgical removal of the primary 'sick' organ contributes to improve clinical outcomes and to reduce immunosuppressive therapy in MG patients. References: 1. Kamradt T, Mitchison NA. N Engl J Med 2001; 344:655-64. 2. Kyewski B, Klein L. Annu Rev Immunol 2006; 24:571-606. 3. Giraud M, Taubert R, Vandiedonck C, et al. Nature 2007; 448:934-7. 4. Geenen V, Bodart G, Henry S, et al. Front Neurosc 2013; 7:art 187. [less ▲]

Detailed reference viewed: 31 (0 ULg)
See detailMany-Body Spin Echo
Engl, Thomas; Urbina, Juan Diego; Richter, Klaus et al

E-print/Working paper (2016)

We predict a universal echo phenomenon present in the time evolution of many-body states of interacting quantum systems described by Fermi-Hubbard models. It consists of the coherent revival of transition ... [more ▼]

We predict a universal echo phenomenon present in the time evolution of many-body states of interacting quantum systems described by Fermi-Hubbard models. It consists of the coherent revival of transition probabilities echoing a sudden flip of the spins that, contrary to its single-particle (Hahn) version, is not dephased by interactions or spin-orbit coupling. The many-body spin echo signal has a universal shape independent of the interaction strength, and an amplitude and sign depending only on combinatorial relations between the number of particles and the number of applied spin flips. Our analytical predictions, based on semiclassical interfering amplitudes in Fock space associated with chaotic mean-field solutions, are tested against extensive numerical simulations confirming that the coherent origin of the echo lies in the existence of anti-unitary symmetries. [less ▲]

Detailed reference viewed: 11 (1 ULg)
Full Text
Peer Reviewed
See detailFrom Dense Hot Jupiter to Low Density Neptune: The Discovery of WASP-127b, WASP-136b and WASP-138b
Lam, K. W. F.; Faedi, F.; Brown, D. J. A. et al

E-print/Working paper (2016)

We report three newly discovered exoplanets from the SuperWASP survey. WASP-127b is a heavily inflated super-Neptune of mass 0.18Mj and radius 1.35Rj. This is one of the least massive planets discovered ... [more ▼]

We report three newly discovered exoplanets from the SuperWASP survey. WASP-127b is a heavily inflated super-Neptune of mass 0.18Mj and radius 1.35Rj. This is one of the least massive planets discovered by the WASP project. It orbits a bright host star (V = 10.16) of spectral type G5 with a period of 4.17 days.WASP-127b is a low density planet which has an extended atmosphere with a scale height of 2500+/-400 km, making it an ideal candidate for transmission spectroscopy. WASP-136b and WASP-138b are both hot Jupiters with mass and radii of 1.51 Mj and 1.38 Rj, and 1.22 Mj and 1.09 Rj, respectively. WASP-136b is in a 5.22-day orbit around an F9 subgiant star with a mass of 1.41 Msun and a radius of 2.21 Rsun. The discovery of WASP-136b could help constraint the characteristics of the giant planet population around evolved stars. WASP-138b orbits an F7 star with a period of 3.63 days. Its radius agrees with theoretical values from standard models, suggesting the presence of a heavy element core with a mass of 10 Mearth. The discovery of these new planets helps in exploring the diverse compositional range of short-period planets, and will aid our understanding of the physical characteristics of both gas giants and low density planets. [less ▲]

Detailed reference viewed: 18 (2 ULg)
See detailWaveguides for walking droplets
Filoux, Boris ULg; Hubert, Maxime ULg; Schlagheck, Peter ULg et al

E-print/Working paper (2016)

When gently placing a droplet onto a vertically vibrated bath, a drop can bounce without coalescing. Upon increasing the forcing acceleration, the droplet is propelled by the wave it generates and becomes ... [more ▼]

When gently placing a droplet onto a vertically vibrated bath, a drop can bounce without coalescing. Upon increasing the forcing acceleration, the droplet is propelled by the wave it generates and becomes a walker with a well defined speed. We investigate the confinement of a walker in different rectangular cavities, used as waveguides for the Faraday waves emitted by successive droplet bounces. By studying the walker velocities, we discover that 1d confinement is optimal for narrow channels of width of D≃1.5λF. We also propose an analogy with waveguide models based on the observation of the Faraday instability within the channels. [less ▲]

Detailed reference viewed: 28 (7 ULg)
Full Text
See detailNouvelles normes sylvicoles pour les peuplements purs équiennes d'épicéa et de douglas
Perin, Jérôme ULg; Hebert, Jacques ULg; Lejeune, Philippe ULg et al

E-print/Working paper (2016)

Ces documents rassemblent les tables de production (version 2016) représentant les nouvelles normes sylvicoles recommandées pour les peuplements purs équiennes d'épicéa commun et de douglas. Un ensemble ... [more ▼]

Ces documents rassemblent les tables de production (version 2016) représentant les nouvelles normes sylvicoles recommandées pour les peuplements purs équiennes d'épicéa commun et de douglas. Un ensemble de 10 tables de production est présentée pour chaque essence, associant deux densités de plantation (2.5 x 2 m et 2 x 2 m) et 5 classes de productivité (0 à IV). [less ▲]

Detailed reference viewed: 344 (46 ULg)
See detailLars Gustafsson, Strindberg et l'ordinateur [critique]
Dupont, Bruno ULg

E-print/Working paper (2016)

Detailed reference viewed: 23 (0 ULg)
Full Text
See detailStein's method, many interacting worlds and quantum mechanics
McKeague, Ian; Peköz, Erol; Swan, Yvik ULg

E-print/Working paper (2016)

Detailed reference viewed: 24 (0 ULg)
Full Text
Peer Reviewed
See detailA class of valid inequalities for multilinear 0-1 optimization problems
Crama, Yves ULg; Rodriguez Heck, Elisabeth ULg

E-print/Working paper (2016)

This paper investigates the polytope associated with the classical standard linearization technique for the unconstrained optimization of multilinear polynomials in 0-1 variables. A new class of valid ... [more ▼]

This paper investigates the polytope associated with the classical standard linearization technique for the unconstrained optimization of multilinear polynomials in 0-1 variables. A new class of valid inequalities, called 2-links, is introduced to strengthen the LP relaxation of the standard linearization. The addition of the 2-links to the standard linearization inequalities provides a complete description of the convex hull of integer solutions for the case of functions consisting of at most two nonlinear monomials. For the general case, various computational experiments show that the 2- links improve both the standard linearization bound and the computational performance of exact branch & cut methods. The improvements are especially significant for a class of instances inspired from the image restoration problem in computer vision. The magnitude of this effect is rather surprising in that the 2-links are in relatively small number (quadratic in the number of terms of the objective function). [less ▲]

Detailed reference viewed: 120 (20 ULg)
Full Text
See detailEarly Detection of University Students in Potential Difficulty
Hoffait, Anne-Sophie ULg; Schyns, Michael ULg

E-print/Working paper (2016)

Using data mining methods, this paper presents a new means of identifying freshmen's profiles likely to face major difficulties to complete their first academic year. Academic failure is a relevant issue ... [more ▼]

Using data mining methods, this paper presents a new means of identifying freshmen's profiles likely to face major difficulties to complete their first academic year. Academic failure is a relevant issue at a time when post-secondary education is ever more critical to economic success. We aim at early detection of potential failure using student data available at registration, i.e. school records and environmental factors, with a view to timely and efficient remediation and/or study reorientation. For the sake of accuracy, we adapt three data mining methods, namely random forest, logistic regression and artificial neural network algorithms. Real data pertaining to undergraduates at the University of Liège (Belgium), illustrates our methodology. [less ▲]

Detailed reference viewed: 30 (9 ULg)
Full Text
See detailDistances between probability distributions via characteristic functions and biasing
Azmoodeh, Ehsan; Arras, Benjamin; Poly, Guillaume et al

E-print/Working paper (2016)

Detailed reference viewed: 41 (5 ULg)
Full Text
See detailStein operators for product distributions, with applications
Mijoule, Guillaume; Gaunt, Robert; Swan, Yvik ULg

E-print/Working paper (2016)

Detailed reference viewed: 19 (0 ULg)
Full Text
See detailAppropriability and the European Commission’s Android Investigation
Auer, Dirk ULg

E-print/Working paper (2016)

This paper seeks to ascertain whether Google’s Android licensing terms, which are currently under scrutiny from the European Commission, could be excused under an innovation defense framework. The paper ... [more ▼]

This paper seeks to ascertain whether Google’s Android licensing terms, which are currently under scrutiny from the European Commission, could be excused under an innovation defense framework. The paper starts by analyzing Google’s business model with regard to its Android OS. It then identifies the Commission’s main concerns. It argues that Google is simply pursuing a sensible appropriation strategy. Finally, it puts forward a framework which hinges on the concept of “appropriability”, and tentatively applies it to Google’s behavior. [less ▲]

Detailed reference viewed: 64 (4 ULg)
Peer Reviewed
See detailSuccess SMB:Leadership Andr Multidimensional Management. An exploratoire Study.
Robert, Jocelyne ULg

E-print/Working paper (2016)

Montre l'importance du leadership comme facteur de succès des PME en croissance rapide (gazelles ). Étude exploratoire.

Detailed reference viewed: 26 (6 ULg)
Full Text
See detailStein's method on the second Wiener chaos : 2-Wasserstein distance
Arras, Benjamin; Mijoule, Guillaume; Poly, Guillaume et al

E-print/Working paper (2016)

Detailed reference viewed: 16 (0 ULg)
See detailPublic Education Expenditures, Growth and Income Inequality
Artige, Lionel ULg; Cavenaile, Laurent

E-print/Working paper (2016)

Detailed reference viewed: 61 (4 ULg)
Full Text
Peer Reviewed
See detailThe Impact of Vulnerability and Resilience to Environmental Changes on Mobility Patterns in West Africa
Zickgraf, Caroline ULg; Vigil Diaz Telenti, Sara ULg; de Longueville, Florence et al

E-print/Working paper (2016)

From the Sahel to the coast, West Africa is experiencing a variety of climate change impacts, including sea level rise, soil salinization, floods, drought, and desertification, while simultaneously ... [more ▼]

From the Sahel to the coast, West Africa is experiencing a variety of climate change impacts, including sea level rise, soil salinization, floods, drought, and desertification, while simultaneously suffering from other forms of environmental degradation. Together, these environmental changes are significantly influencing migration patterns in and out of West Africa. This paper seeks to analyze vulnerability and resilience to environmental changes as they affect and are affected by mobility patterns in the region. We assert that the impact of environmental changes cannot be isolated from other political, social, economic, and demographic pressures that together drive human mobility. In a region where natural resources form the foundation of livelihoods and food security (fishing and agriculture), the relationship between environmental changes and socioeconomic vulnerabilities is of particular concern. This paper therefore draws from four distinct case studies to grasp the variegated and cumulative vulnerability and resilience among local populations as they relate to internal and intraregional migration. [less ▲]

Detailed reference viewed: 129 (9 ULg)
See detailLe législateur wallon sommé de revoir le découpage des circonscriptions électorales
Bouhon, Frédéric ULg

E-print/Working paper (2016)

Le caractère proportionnel de notre système électoral n’est pas un vain mot et ne peut être contourné. C’est ce que viennent de rappeler deux arrêts, le premier, prononcé par le Conseil d’État, datant du ... [more ▼]

Le caractère proportionnel de notre système électoral n’est pas un vain mot et ne peut être contourné. C’est ce que viennent de rappeler deux arrêts, le premier, prononcé par le Conseil d’État, datant du 20 novembre 2014 (n° 229.252) , le second, rendu par la Cour constitutionnelle le 26 novembre 2015 (n° 169/2015) . Le Parlement wallon doit revoir la carte électorale en vue des prochaines élections. [less ▲]

Detailed reference viewed: 25 (6 ULg)
Full Text
Peer Reviewed
See detailRevealing the role of network rigidity on the fragility evolution of glass-forming liquids
Yildirim, Can ULg; Raty, Jean-Yves ULg; Micoulaut, Mathieu

E-print/Working paper (2016)

If quenched fast enough, a liquid is able to avoid crystallization and will remain in a metastable supercooled state down to the glass transition, with an important increase in viscosity and relaxation ... [more ▼]

If quenched fast enough, a liquid is able to avoid crystallization and will remain in a metastable supercooled state down to the glass transition, with an important increase in viscosity and relaxation time towards equilibrium upon further cooling [1,2]. There are important differences in the way liquids relax as they approach the glass transition, rapid or slow variation in dynamic quantities under moderate temperature changes, and a simple means to quantify such variations is provided by the concept of "fragility". Here, we report molecular dynamics simulations of a typical network-forming glass, and find that the relaxation behaviour of the supercooled liquid is strongly correlated to the variation of rigidity with temperature and the spatial distribution of the corresponding topological constraints which, ultimately connect to fragility minima . This permits extending the fragility concept to aspects of topology/rigidity, and to the degree of homogeneity of the atomic-sale interactions for a variety of structural glasses. [less ▲]

Detailed reference viewed: 37 (6 ULg)
Full Text
See detailCore Content Classification in General Practice Family medicine (3CGP) The Q-Codes user guide
Jamoulle, Marc ULg

E-print/Working paper (2016)

user guide and general explanation pages for the Q-codes, a classification of managerial issues in General Practice / Family Medicine

Detailed reference viewed: 41 (3 ULg)
Full Text
See detailL’aménagement forestier au Congo engendre-t-il plus de déforestation ?
Karsenty, Alain; Cerutti, P.; Doucet, Jean-Louis ULg et al

E-print/Working paper (2016)

Un article publié dans Land Use Policy début 2016 arrive à la conclusion a priori étonnante que la déforestation serait, au Congo, plus élevée dans les concessions forestières avec des plans d’aménagement ... [more ▼]

Un article publié dans Land Use Policy début 2016 arrive à la conclusion a priori étonnante que la déforestation serait, au Congo, plus élevée dans les concessions forestières avec des plans d’aménagement que dans celles qui n’en ont pas. L’analyse d’évaluation d’impact qui a conduit ces chercheurs à un tel résultat se base sur un appariement de parcelles sélectionnées aléatoirement dans des concessions avec et sans plans d’aménagement. Ces chercheurs indiquent que le réseau de routes forestières plus développé dans les concessions aménagées serait un des facteurs explicatifs. L’autre facteur serait le développement local lié aux cahiers des charges des plans d’aménagement, lequel conduirait à une augmentation de la population dans ces concessions et à une déforestation accrue. Notre groupe d’une vingtaine de chercheurs connaissant bien la problématique de l’aménagement forestier en Afrique centrale s’est penché à son tour sur cette question et a analysé la déforestation au niveau des concessions sur le même intervalle de temps. Nos résultats montrent, cette fois, que la déforestation est moins importante dans les concessions avec un plan d’aménagement que dans les autres. Et si l’on compare à production égale la déforestation dans des concessions avec et sans plan d’aménagement, il apparaît que les UFA aménagées sont environ deux fois plus « efficaces », c’est-à-dire qu’on observe deux fois moins de perte de couvert forestier par mètre-cube produit. Nous en concluons qu’il est nécessaire d’analyser précisément la dynamique des différents facteurs de déforestation, et éviter d’imputer mécaniquement à l’aménagement forestier un rôle excessif dans l’évolution dans un sens ou dans l’autre du taux de déboisement. Enfin, toute évaluation doit rappeler que les effets de l’aménagement forestier doivent être mesurés sur le long terme : l’objectif de l’aménagement est de permettre une mise en valeur forestière durable, en conservant l’essentiel du capital productif pour éviter, autant que possible, la conversion à d’autres usages après les cycles de coupe initiaux. [less ▲]

Detailed reference viewed: 99 (5 ULg)
See detailFive years on for Fukushima's IDPs: Life with radiological risk and without a community safety net
Hasegawa, Reiko ULg

E-print/Working paper (2016)

On the fifth anniversary of the Fukushima nuclear accident, the article analyses what are at stake in the communities affected by the disaster, based on the result of the field interviews conducted in ... [more ▼]

On the fifth anniversary of the Fukushima nuclear accident, the article analyses what are at stake in the communities affected by the disaster, based on the result of the field interviews conducted in Fukushima. [less ▲]

Detailed reference viewed: 23 (0 ULg)
Full Text
See detailSouthern Blues Night , Heerlen (Hollande) 19 mars 2016
Sacré, Robert ULg

E-print/Working paper (2016)

Compte rendu de la Southern Blues Night annuelle de Heerlen aux Pays Bas, avec photos

Detailed reference viewed: 21 (0 ULg)
Full Text
See detailNote on the numerical solution of the scalar Helmholtz equation in a nanotorus with uniform Dirichlet boundary conditions
Nguyen, Ngoc Duy ULg; Evrard, Roger ULg; Stroscio, Michael

E-print/Working paper (2016)

This note describes the solution of the Helmholtz equation inside a nanotorus with uniform Dirichlet boundary conditions. The eigenfunction symmetry is discussed and the lower-order eigenvalues and ... [more ▼]

This note describes the solution of the Helmholtz equation inside a nanotorus with uniform Dirichlet boundary conditions. The eigenfunction symmetry is discussed and the lower-order eigenvalues and eigenfunctions are shown. The similarity with the case of a long cylinder and with that of the vibrations of a circular elastic membrane is discussed. This similarity is used to propose a classification scheme of the eigenfunctions based on three indices. [less ▲]

Detailed reference viewed: 50 (8 ULg)
Full Text
See detailThe Smallest Salable Patent-Practicing Unit ('SSPPU') Experiment, General Purpose Technologies and the Coase Theorem
Petit, Nicolas ULg

E-print/Working paper (2016)

In the last years, some Standard-Setting Organizations (“SSOs”) active in wireless communications have experimented new pricing principles for standard essential patents (“SEPs”). One of those experiments ... [more ▼]

In the last years, some Standard-Setting Organizations (“SSOs”) active in wireless communications have experimented new pricing principles for standard essential patents (“SEPs”). One of those experiments is the “SSPPU” rule. Under SSPPU, the licensing rates paid to owners of SEPs for the use of their technology shall reflect the “value that the functionality of the claimed invention or inventive feature…contributes to the value of the relevant functionality of the smallest saleable Compliant Implementation that practices the Essential Patent Claim”. This paper reviews the SSPPU experiment through the lenses of the Coase theorem. It finds that SSPPU interferes with the efficient operation of the price system, and is likely to reduce investment in socially beneficial activities, including in General Purpose Technologies (“GPTs”) which are key drivers of economic growth. [less ▲]

Detailed reference viewed: 44 (1 ULg)
Full Text
See detailLa diversité des expressions culturelles au tourbillon du numérique
Vlassis, Antonios ULg

E-print/Working paper (2016)

Detailed reference viewed: 46 (3 ULg)
Full Text
See detailSome characterizations about Generalized Hölder-Zygmund Spaces Λ_{σ,N}^{α}(R^d)
Kreit, Damien ULg; Nicolay, Samuel ULg

E-print/Working paper (2016)

Generalized Hölder-Zygmund spaces $\Lambda_{\sigma, N}^{\alpha}(\R^{d})$ were recently introduced and are based on a generalization of Besov spaces. Under some conditions, generalized Hölder-Zygmund and ... [more ▼]

Generalized Hölder-Zygmund spaces $\Lambda_{\sigma, N}^{\alpha}(\R^{d})$ were recently introduced and are based on a generalization of Besov spaces. Under some conditions, generalized Hölder-Zygmund and Besov spaces are equal. It has been proved that most properties of classical Hölder-Zygmund spaces are held for spaces $\Lambda^{\sigma,\alpha}(\R^{d})$, which constitute a particular case of spaces $\Lambda_{\sigma, N}^{\alpha}(\R^{d})$ with $N_{j}=2^{j}$. The goal of the present document is to prove that most of these properties are kept for $\Lambda_{\sigma, N}^{\alpha}(\R^{d})$ spaces. [less ▲]

Detailed reference viewed: 16 (2 ULg)
Full Text
Peer Reviewed
See detailA Comparison of Departure Time of Day Formulations
Lurkin, Virginie ULg; Garrow, Laurie; Higgins, Matthew et al

E-print/Working paper (2016)

Airline passengers’ itinerary choices are influenced by many factors including carriers, prices, the number of connections, and departure times. This paper compares three different methods that have been ... [more ▼]

Airline passengers’ itinerary choices are influenced by many factors including carriers, prices, the number of connections, and departure times. This paper compares three different methods that have been used to model departure time of day preferences. The first is a discrete formulation that uses indicator variables to represent the hour of departure. The next two methods are based on a continuous formulation that uses a series of sine and cosine functions. One assumes departure time preferences over a 24-hour cycle and the other uses shorter cycle lengths that account for fewer departures during certain hours of the day. We compare models using itineraries in the Continental U.S. that are separated by two time zones. Although the discrete formulation fits the data better, the two continuous time of day formulations are preferred as they provide more intuitive predictions and require fewer parameters. Results between the two continuous time of day formulations are similar but differ in how strongly they weight itineraries that depart very early or very late in the day. Based on empirical results, we recommend testing both 24-hour and less than 24-hour cycle lengths for a particular dataset. [less ▲]

Detailed reference viewed: 18 (6 ULg)
Full Text
See detailContinuous Departure Time of Day Preferences for Continental U.S. Airline Markets Segmented by Distance, Direction of Travel, Number of Time Zones, Day of Week and Itinerary Type
Lurkin, Virginie ULg; Garrow, Laurie; Higgins, Matthew et al

E-print/Working paper (2016)

Airlines use itinerary choice models to allocate the total number of passengers in a city pair to specific itineraries. In a related paper, we estimated a multinomial logit (MNL) itinerary choice model ... [more ▼]

Airlines use itinerary choice models to allocate the total number of passengers in a city pair to specific itineraries. In a related paper, we estimated a multinomial logit (MNL) itinerary choice model using database of more than 3 million tickets for Continental U.S. markets provided by the Airlines Reporting Corporation that accounted for price endogeneity. The size and comprehensiveness of our database allowed us to estimate highly refined continuous departure time of day preference curves that account for distance, direction of travel, the number of time zones traversed, departure day of week and itinerary type (outbound, inbound or one-way). This paper and accompanying Excel spreadsheet located at http://garrowlab.ce.gatech.edu contain the results of all model coefficients (including the 1260 time of day parameters) and summarize results in a series of ten figures. These highly-refined time of day preference curves can be used by airlines, researchers, and government organizations in the evaluation of demand-management and other policies. [less ▲]

Detailed reference viewed: 74 (4 ULg)
Full Text
Peer Reviewed
See detailAccounting for Price Endogeneity in Airline Itinerary Choice Models: An Application to Continental U.S. Markets
Lurkin, Virginie ULg; Garrow, Laurie; Higgins, Matthew et al

E-print/Working paper (2016)

Network planning models, which forecast the profitability of airline schedules, support many critical decisions, including equipment purchase decisions. Network planning models include an itinerary choice ... [more ▼]

Network planning models, which forecast the profitability of airline schedules, support many critical decisions, including equipment purchase decisions. Network planning models include an itinerary choice model which is used to allocate air total demand in a city pair to different itineraries. Multinomial logit (MNL) models are commonly used in practice and capture how individuals make trade-offs among different itinerary attributes; however, none that we are aware of account for price endogeneity. This study formulates an itinerary choice model that is consistent with those used by industry and corrects for price endogeneity using a control function that uses several types of instrumental variables. We estimate our models using database of more than 3 million tickets provided by the Airlines Reporting Corporation. Results based on Continental U.S. markets for May 2013 departures show that models that fail to account for price endogeneity overestimate customers’ value of time and result in biased price estimates and incorrect pricing recommendations. The size and comprehensiveness of our database allows us to estimate highly refined departure time of day preference curves that account for distance, direction of travel, the number of time zones traversed, departure day of week and itinerary type (outbound, inbound or one-way). These time of day preference curves can be used by airlines, researchers, and government organizations in the evaluation of different policies such as congestion pricing. [less ▲]

Detailed reference viewed: 31 (6 ULg)
Full Text
See detailPolitique de la Ville : Dynamisation des coeurs de ville
Bastin, Florine ULg; Lacroix, Gilles; May, Xavier et al

E-print/Working paper (2016)

La régionalisation de la Politique Fédérale des Grandes Villes, suite à la sixième réforme de l’Etat, fut une opportunité de s’interroger sur les objectifs et l’organisation d’une Politique de la Ville en ... [more ▼]

La régionalisation de la Politique Fédérale des Grandes Villes, suite à la sixième réforme de l’Etat, fut une opportunité de s’interroger sur les objectifs et l’organisation d’une Politique de la Ville en Wallonie. Dans ce cadre, la note de recherche CPDT n°63 « Politique de la ville. Dynamisation des cœurs de ville » répond à la volonté du Gouvernement wallon de se doter d’une vision territoriale stratégique sur le long terme et est un premier pas vers la mise en place d’une politique de la ville intégrée en Wallonie. Cette note fait le point sur, d’une part, les différentes politiques et outils relatifs à la restructuration et à la dynamisation des tissus urbains, au sens large, établis au niveau régional, fédéral et européen et, d’autre part, les propositions et recommandations relatives à l’évolution du cadre actuel. Cette réflexion s’adresse évidemment aux acteurs concernés par les enjeux de gouvernance urbaine : les décideurs politiques, les villes et les communes mais concerne aussi le citoyen. [less ▲]

Detailed reference viewed: 112 (11 ULg)
Full Text
See detailStructure et négativité dans la Préface de 1961 à L'Histoire de la folie
Oulc'hen, Hervé ULg

E-print/Working paper (2016)

Detailed reference viewed: 20 (2 ULg)
Peer Reviewed
See detailHistoires de rayons verts : phénomène physique, critique de cinéma, spectateurs mélancoliques
Barbion, Sébastien ULg

E-print/Working paper (2016)

En s’appuyant sur la physique, un roman de Jules Verne et un film de Rohmer, ce texte déplie les différents aspects théoriques et pratiques contenus dans le concept de rayon vert : un type de perception ... [more ▼]

En s’appuyant sur la physique, un roman de Jules Verne et un film de Rohmer, ce texte déplie les différents aspects théoriques et pratiques contenus dans le concept de rayon vert : un type de perception, une manière de concevoir la critique de cinéma, une expérience de spectateur. [less ▲]

Detailed reference viewed: 26 (3 ULg)
Full Text
See detailOlder men’s labor force participation in Belgium
Jousten, Alain ULg; Lefebvre, Mathieu ULg

E-print/Working paper (2016)

We provide an overview of the institutional framework in Belgium that is of relevance for labor market participation and retirement decision at older ages. We then describe key labor market indicators ... [more ▼]

We provide an overview of the institutional framework in Belgium that is of relevance for labor market participation and retirement decision at older ages. We then describe key labor market indicators using data from the Labour Force Survey (LFS) over the period 1983-2013 and also present trends in participation in (early-) retirement routes. Next, we explore how the types of jobs in the country have changed over time, both in terms of their “quality” and the “quantity” of work involved. [less ▲]

Detailed reference viewed: 27 (8 ULg)
Full Text
See detailRésumé de la thèse: Rôle du climat et de la compétition interspécifique dans la limitation de l'aire d'invasion d'Ambrosia artemisiifolia L. en Europe de l'Ouest
Ortmans, William ULg

E-print/Working paper (2016)

The invasion continuum is classically described from a temporal point of view, where a species overcomes a defined number of barriers linked to the environment. First, an exotic species has to get through ... [more ▼]

The invasion continuum is classically described from a temporal point of view, where a species overcomes a defined number of barriers linked to the environment. First, an exotic species has to get through the geographical barrier, in order to be introduced in the new area. When introduced, the species has to face the new environmental conditions and survive to start the naturalization phase. When the environmental barrier is overcome, i.e. when the species is able to reproduce and its populations are self-sufficient, it has to overcome the dispersal barrier to spread in the ecosystem and finally become invasive. Within a given continent, a species could have overcome a variable number of barriers depending on the considered area. One can observe depending on the geographical zone some non-naturalized populations that cannot survive without a human introduction of new propagules, some naturalized populations that are not invasive yet, and some invasive populations. This geographical variation may be the result of a variation of the environmental conditions at the continental scale. The common ragweed (Ambrosia artemisiifolia L.) invasion in Western Europe is a good opportunity to study this aspect of the invasion biology. The invasion history and the species distribution are well documented, and highlight a geographical variation of the invasion dynamic. This is particularly clear in Western Europe, where lies a contrast between the highly invaded zone of the South of France, and the areas that are farther north (e.g. the North of France, Belgium, and the Netherlands). In this work, the general objective was to determine if this situation will remain stable or not, by assessing if the local climate and the interspecific competition were liming the species expansion northward. In order to answer this general objective, four different questions were asked: 1) Is the climate and/or the interspecific competition causing a plant performance variation within the different areas of the introduced range in Western Europe?; 2) Is the local climate allowing the establishment and the reproduction of newly introduced populations north to the current invaded range, in an agricultural habitat?; 3) What is the role of the morphological variability of the seeds in the invasion of areas experiencing rigorous climatic conditions?; and 4) What is the role of the priority effect in the species establishment? The results showed that once introduced in an agricultural habitat outside the current invaded range, the species was able to establish self-sustaining populations. On average, each plant produced a number of offspring equal to 273 ± 18.4 (mean ± standard error). In ruderal habitats, populations already exist in Belgium and in the South of The Netherlands, and are able to produce a high quantity of seeds: on average, measured plants carried 222± 32.0 seeds. The measured plant performances were similar to those measured within the invaded area. No limit to the colonization of the area beyond the current invaded range was found in this study. The local climate and the interspecific competition did not appear to limit the naturalization of the species in the studied area, which is located north to the current invaded range, in agricultural or ruderal situations. This work highlighted the obsolescence of the species status in Belgium, and illustrated the dynamic aspect of the invasion. The results showed the importance of the temporality in the colonization of disturbed habitats. When the species started its development a few weeks before the rest of the community, its performance was decupled, and this increase was higher than the one other Asteraceae ruderals species showed in the same position: its above ground biomass was 30.5 ± 1.94 times higher, and the number of flower heads 570 ± 160 times more important.. The high variability of the species observed all along this work is probably playing an important role in the invasion success. The high variability of the seeds morphology can widen the range of environmental conditions of the habitats the species is able to colonize. In addition, the plasticity of the morphological traits of the plant in response to climate and competition appeared to allow the species to maintain a good performance, even in stressful conditions. The results of this work suggest an invasion potential north to the current invaded area in Western Europe. In this uncertain situation, it appears critical to implement structure allowing the early detection of the species. This early detection may allow the eradication of the species before that the invasion was as problematic as in France. Sensitization campaigns of the agricultural sector should be encouraged in Belgium in order to avoid new occurrence of the species in field to be overlooked. These measures could allow the dispersion to remain a limiting factor for the invasion process in Belgium. [less ▲]

Detailed reference viewed: 170 (80 ULg)
Full Text
See detailA useful result related with zeros of continuous compactly supported mother wavelets
Ayache, Antoine; Esser, Céline ULg

E-print/Working paper (2016)

In the last two decades, wavelet bases and associated methodologies have become quite important in many domains, such as signal and image processing, harmonic analysis, statistics, and so on. More ... [more ▼]

In the last two decades, wavelet bases and associated methodologies have become quite important in many domains, such as signal and image processing, harmonic analysis, statistics, and so on. More recently, they also turn out to be quite useful in the probabilistic framework of stochastic processes, in which, among other things, they allow to obtain fine results concerning erratic sample paths behavior. The goal of our article is to derive a result, related with zeros of continuous compactly supported mother wavelets, which is useful in this probabilistic framework. More precisely, let $\psi$ be any arbitrary such wavelet; we show that being given an arbitrary point $x_0\in\R$ there always exists at least one integer $k_{x_0}\in\Z$ such that $\psi(x_0-k_{x_0}) \neq 0$. [less ▲]

Detailed reference viewed: 22 (4 ULg)
Full Text
See detailHedge fund styles and macroeconomic uncertainty
Platania, Federico ULg; Lambert, Marie ULg

E-print/Working paper (2016)

This paper examines the dynamic trading strategies implemented by hedge fund managers using a Kalman filter of hedge fund betas across styles. We further investigate the risk drivers of dynamic trades ... [more ▼]

This paper examines the dynamic trading strategies implemented by hedge fund managers using a Kalman filter of hedge fund betas across styles. We further investigate the risk drivers of dynamic trades, examining which conditioning/macroeconomic variables strongly lead the time variation in fund trades. We report the significance of macroeconomic factors such as interest rates, dividend yield, GDP growth and US unemployment. We show that hedge fund managers do control the intensity of their exposures according to economic uncertainty and that differences between up- and down-market regimes can be observed. Commonly, Hedge funds tend to dislike high-dividend paying stocks. Besides, all hedge fund styles are shown to display pro-cyclical exposures towards directional equity factors as well as credit and liquidity risks. Small growth stocks, however, are revealed to be crisis investments whose allocation increases with unemployment, inflation or volatility. As volatility increases, the value of growth options embedded into growth stocks indeed increases. Growth stocks are shown to hedge market reversals and volatility. The outperformance of growth companies in recessions might also relate to their cost flexibility. Allocation to small stocks embed strong micro risks and might also constitute a hedge in economic slowdowns. This might explain why some funds with such a particular investment focus appear to be countercyclical. [less ▲]

Detailed reference viewed: 25 (2 ULg)
Full Text
Peer Reviewed
See detailAnalyse comparative des résultats économiques de la production rizicole dans les pays de la CEPGL
Furaha Mirindi, Germaine ULg; Mastaki, Jean-Luc; Lebailly, Philippe ULg

E-print/Working paper (2016)

Cet article fait une analyse comparative des résultats économiques de la production rizicole durant la saison B 2014 dans les trois pays de la CEPGL qui sont la République Démocratique du Congo, le Rwanda ... [more ▼]

Cet article fait une analyse comparative des résultats économiques de la production rizicole durant la saison B 2014 dans les trois pays de la CEPGL qui sont la République Démocratique du Congo, le Rwanda et le Burundi. L’approche comparative permet de trouver les explications des différences des résultats en partie dans les politiques mises en oeuvre dans chaque pays. Les enquêtes ont été menées dans la plaine de la Ruzizi partagée entre les trois pays auprès de 240 producteurs du riz choisi à partir de la méthode des quotas sur la base d'une stratification des exploitations rizicoles. Dans le site congolais (où il est plus difficile d’accéder aux intrants et crédits), les coûts de production d’1kg de paddy sont les plus élevés avec une fonction de production y=0,034x+0,053z+0,422 et le rendement le plus bas (2698kgs). Par contre, dans les sites burundais et rwandais où l’Etat intervient dans l’approvisionnement en intrants et particulièrement dans le site rwandais, l’accès aux crédits, les fonctions de production sont respectivement de y=0,024x+0,031z+0,297 et y=0,017x+0,023z+0,269 avec des rendements de 3962kgs et 5339kgs dans le même ordre. Les coûts de production supportés sur un hectare rizicole ou encore pour la production d’une tonne de paddy varient selon le pays car ils dépendent de la valeur des intrants utilisés et des autres charges de structures. Ils varient ainsi de 1139,4USD à 1354,5USD/ ha et de 269 à 422USD/tonne. [less ▲]

Detailed reference viewed: 20 (4 ULg)
Full Text
See detailNonparametric control charts: economic statistical design
Marcos Alvarez, Alejandro ULg; Heuchenne, Cédric ULg; Faraz, Alireza ULg

E-print/Working paper (2016)

This paper studies economic statistical designs (ESD) for nonparametric control charts based on the sign and Wilcoxon tests. The main advantage of the procedures is that, except for the tested location ... [more ▼]

This paper studies economic statistical designs (ESD) for nonparametric control charts based on the sign and Wilcoxon tests. The main advantage of the procedures is that, except for the tested location parameter, they do not use either any parametric distribution for the quality characteristic or any information about the possible involved parameters, neither in the in-control nor in the out-of-control state. This is made possible by minimizing a cost function specified independently of these quantities. Unlike the ESD for the $\overline{x}$ chart, the resulting charts designs are robust to changes of the distributions of the observations (in control or out of control), provide reliable statistical guarantees when the $\overline{x}$ chart ESD does not and stay competitive even when the strong assumptions of the $\overline{x}$ chart ESD are fully satisfied. These new techniques can therefore be applied to a definitely wider class of problems and their designs may stay constant over time without losing performance. [less ▲]

Detailed reference viewed: 78 (3 ULg)
Full Text
See detailOnline Learning for Strong Branching Approximation in Branch-and-Bound
Marcos Alvarez, Alejandro ULg; Wehenkel, Louis ULg; Louveaux, Quentin ULg

E-print/Working paper (2016)

We present an online learning approach to variable branching in branch-and-bound for mixed-integer linear problems. Our approach consists in learning strong branching scores in an online fashion and in ... [more ▼]

We present an online learning approach to variable branching in branch-and-bound for mixed-integer linear problems. Our approach consists in learning strong branching scores in an online fashion and in using them to take branching decisions. More specifically, numerical scores are used to rank the branching candidates. If, for a given variable, the learned approximation is deemed reliable, then the score for that variable is computed thanks to the learned function. If the approximation is not reliable yet, the real strong branching score is used instead. The scores that are computed through the real strong branching procedure are fed to the online learning algorithm in order to improve the approximated function. The experiments show promising results. [less ▲]

Detailed reference viewed: 75 (4 ULg)
Full Text
See detailOn the processing of red pigment by late mousterian Neanderthals in Ormesson, Seine-et-Marne, France, 47000 years ago
Salomon, Hélène ULg; Bodu, Pierre; Geurten, Stéphanie et al

E-print/Working paper (2016)

Detailed reference viewed: 27 (8 ULg)
Full Text
See detailBispecial factors in the Brun S-adic system
Labbé, Sébastien ULg; Leroy, Julien ULg

E-print/Working paper (2016)

Detailed reference viewed: 34 (5 ULg)
Full Text
See detailA stroll along the gamma
Arras, Benjamin ULg; Swan, Yvik ULg

E-print/Working paper (2016)

Detailed reference viewed: 78 (11 ULg)
Full Text
Peer Reviewed
See detailFundamentals for an International Typology of Social Enterprise Models
Defourny, Jacques ULg; Nyssens, Marthe

E-print/Working paper (2016)

Detailed reference viewed: 61 (6 ULg)
See detailRossano Rosi, "Hanska": un roman en "feuilleté"
Demoulin, Laurent ULg

E-print/Working paper (2016)

Compte rendu du beau roman de Rossano Rosi "Hanska"

Detailed reference viewed: 13 (0 ULg)
Full Text
See detailMarket efficiency and hedge fund trading strategies
Platania, Federico ULg; Lambert, Marie ULg; Papageorgiou, Nicolas

E-print/Working paper (2016)

Stock and option markets can at times reflect differing information. We identify three reasons for the presence of these periods of "disagreement" between the cash and derivatives markets: 1) high ... [more ▼]

Stock and option markets can at times reflect differing information. We identify three reasons for the presence of these periods of "disagreement" between the cash and derivatives markets: 1) high volatility and noise trading; 2) high level of risk aversion; 3) speculation versus hedging trades. This paper investigates the role that hedge funds, a proxy for sophisticated investors, play in the price discovery process between stock and option markets and the disagreement/agreement periods. We observe that a disparity in information between the two markets is often associated with deleveraging in directional exposures and reversal strategies. Posterior to the event, active tactical asset allocation in small and value factor investing takes place. We investigate four specific macro events which resulted in significant rebalancing by hedge fund manegers: the Thai Baht depreciation, the Dot-com bubble, the credit crunch and the Nasdaq correction. [less ▲]

Detailed reference viewed: 22 (2 ULg)
Full Text
See detailHST-Juno synergistic approach of Jupiter's magnetosphere and ultraviolet auroras
Grodent, Denis ULg; Bonfond, Bertrand ULg; Gérard, Jean-Claude ULg et al

E-print/Working paper (2016)

Jupiter's system is not only fundamental to our understanding of the solar system but also of planetary systems around other stars as well as more distant astrophysical bodies, not accessible to a ... [more ▼]

Jupiter's system is not only fundamental to our understanding of the solar system but also of planetary systems around other stars as well as more distant astrophysical bodies, not accessible to a detailed investigation. Fully exploiting any rare opportunity to explore the Jovian system through synergistic observations is thus critical, as it will impact significantly across wider astronomical studies. Such an exceptional opportunity will occur in Cycle 24, when the NASA Juno spacecraft will achieve its prime mission around Jupiter. Since Juno will literally fly through the auroral acceleration regions, the combination of HST auroral observations with Juno in situ measurements will allow us to finally unravel the origins and consequences of Jupiter's powerful and highly variable ultraviolet auroras. This occasion has never occurred before and is unlikely to ever repeat. Juno will address key scientific issues related to unexplored regions of the Jovian magnetosphere. The auroral signatures associated with these magnetospheric processes will be precisely observed with STIS and COS. This program responds to the UV initiative and is only possible during Cycle 24. Indeed, HST is the only observatory capable of making these high spatial and temporal resolution FUV observations during the Juno mission. This ambitious campaign will yield high-impact results and significantly augment the science return of the NASA Juno mission. [less ▲]

Detailed reference viewed: 63 (4 ULg)
Full Text
See detailFisheries reforms and right-based fisheries: insights from community fisheries across Cambodia
Chap, Sreyphea; Touch, Panha; Diepart, Jean-Christophe ULg

E-print/Working paper (2016)

The working paper uses a right-based approach to examine recent wave of reforms in the Cambodian fisheries sector and what these reforms mean for community fisheries management.

Detailed reference viewed: 51 (2 ULg)
Full Text
See detailALPI project - Green Incentives : Belgian and European Aspects
Bourgeois, Marc ULg; Vanrykel, Fanny ULg; Defoy, Xavier ULg

E-print/Working paper (2016)

Finance is one of the main critical issues for the development of a low-carbon society especially during times of economic recession. Closing this green investment gap will require policy intervention ... [more ▼]

Finance is one of the main critical issues for the development of a low-carbon society especially during times of economic recession. Closing this green investment gap will require policy intervention. The ALPI project will concentrate on promoting relevant ins truments to accelerate the transition towards a low-carbon society by demonstrating the performance and impact of policy instruments on economic, government budget and environmental aspects. [less ▲]

Detailed reference viewed: 22 (0 ULg)
Full Text
See detailFeasibility-oriented Branching Strategies for Global Optimization
Gerard, Damien ULg; Köppe, Matthias; Louveaux, Quentin ULg

E-print/Working paper (2016)

We study the spatial Brand-and-Bound algorithm for the global optimization of nonlinear problems. In particular we are interested in a method to find quickly good feasible solutions. Most spatial Branch ... [more ▼]

We study the spatial Brand-and-Bound algorithm for the global optimization of nonlinear problems. In particular we are interested in a method to find quickly good feasible solutions. Most spatial Branch-and-Bound-based solvers use a non global solver at a few nodes to try to find better incumbents. We show that it is possible to improve the branching rules and the node priority by exploiting the solutions from the non global solver. We also propose several smart adaptive strategies to choose when to run the non global solver. We show that despite the time spent in solving many more NLP problems in the nodes, the new strategies enable the algorithm to find the first good incumbents faster and to prove the global optimality faster. Numerous easy, medium size as well as hard NLP instances from the Coconut library are benchmarked. All experiments are run using the open source solver Couenne. [less ▲]

Detailed reference viewed: 32 (8 ULg)