References of "E-prints/Working papers"      in Complete repository Arts & humanities   Archaeology   Art & art history   Classical & oriental studies   History   Languages & linguistics   Literature   Performing arts   Philosophy & ethics   Religion & theology   Multidisciplinary, general & others Business & economic sciences   Accounting & auditing   Production, distribution & supply chain management   Finance   General management & organizational theory   Human resources management   Management information systems   Marketing   Strategy & innovation   Quantitative methods in economics & management   General economics & history of economic thought   International economics   Macroeconomics & monetary economics   Microeconomics   Economic systems & public economics   Social economics   Special economic topics (health, labor, transportation…)   Multidisciplinary, general & others Engineering, computing & technology   Aerospace & aeronautics engineering   Architecture   Chemical engineering   Civil engineering   Computer science   Electrical & electronics engineering   Energy   Geological, petroleum & mining engineering   Materials science & engineering   Mechanical engineering   Multidisciplinary, general & others Human health sciences   Alternative medicine   Anesthesia & intensive care   Cardiovascular & respiratory systems   Dentistry & oral medicine   Dermatology   Endocrinology, metabolism & nutrition   Forensic medicine   Gastroenterology & hepatology   General & internal medicine   Geriatrics   Hematology   Immunology & infectious disease   Laboratory medicine & medical technology   Neurology   Oncology   Ophthalmology   Orthopedics, rehabilitation & sports medicine   Otolaryngology   Pediatrics   Pharmacy, pharmacology & toxicology   Psychiatry   Public health, health care sciences & services   Radiology, nuclear medicine & imaging   Reproductive medicine (gynecology, andrology, obstetrics)   Rheumatology   Surgery   Urology & nephrology   Multidisciplinary, general & others Law, criminology & political science   Civil law   Criminal law & procedure   Criminology   Economic & commercial law   European & international law   Judicial law   Metalaw, Roman law, history of law & comparative law   Political science, public administration & international relations   Public law   Social law   Tax law   Multidisciplinary, general & others Life sciences   Agriculture & agronomy   Anatomy (cytology, histology, embryology...) & physiology   Animal production & animal husbandry   Aquatic sciences & oceanology   Biochemistry, biophysics & molecular biology   Biotechnology   Entomology & pest control   Environmental sciences & ecology   Food science   Genetics & genetic processes   Microbiology   Phytobiology (plant sciences, forestry, mycology...)   Veterinary medicine & animal health   Zoology   Multidisciplinary, general & others Physical, chemical, mathematical & earth Sciences   Chemistry   Earth sciences & physical geography   Mathematics   Physics   Space science, astronomy & astrophysics   Multidisciplinary, general & others Social & behavioral sciences, psychology   Animal psychology, ethology & psychobiology   Anthropology   Communication & mass media   Education & instruction   Human geography & demography   Library & information sciences   Neurosciences & behavior   Regional & inter-regional studies   Social work & social policy   Sociology & social sciences   Social, industrial & organizational psychology   Theoretical & cognitive psychology   Treatment & clinical psychology   Multidisciplinary, general & others     Showing results 1 to 100 of 661 1 2 3 4 5 6     AuraDurand, Pascal E-print/Working paper (in press)Entrée du Lexique Socius sur le concept d'Aura chez Walter BenjaminDetailed reference viewed: 48 (2 ULg) Approche agroforestière. Synthèse des travaux menés par le projet DACEFI2 en agroforesterie. Document de capitalisation.Boldrini, Sylvie; Meunier, Quentin; Boukouendji, Basile et alE-print/Working paper (2015)Le projet DACEFI-2 a eu pour mission première la promotion de la foresterie communautaire comme outil de développement des communautés rurales. L’approche au Gabon en matière de gestion des terroirs ... [more ▼]Le projet DACEFI-2 a eu pour mission première la promotion de la foresterie communautaire comme outil de développement des communautés rurales. L’approche au Gabon en matière de gestion des terroirs villageois s’est voulue plus embrassante, promouvant en sus de l’exploitation forestière des activités comme l’agriculture, le maraîchage, la collecte des produits forestiers non ligneux ou encore l’agroforesterie. L’agroforesterie est une thématique qui converge parfaitement avec la gestion raisonnée de la forêt, et idéalement avec les modes d’interaction préexistants des villageois avec celle-ci. Concilier dans un même espace la culture de plantes vivrières et l’accès à des arbres à fort intérêt socio-économique apporte une plus-value notoire aux parcelles cultivées. L’optimisation des techniques culturales permet une meilleure productivité et une incitation à la sédentarisation des cultures, élément important à considérer compte tenu des difficultés d’entretien des parcelles éloignées du village (notamment liées aux dégâts causés par les animaux). Ce recueil compile les travaux réalisés en agroforesterie par les équipes du projet DACEFI-2. Il rappelle la stratégie d’intervention et les différentes activités menées, de la sensibilisation auprès des plus jeunes à la promotion de certains produits forestiers non ligneux à potentiel économique avéré. La promotion de l’arbre, de la récolte de la graine jusqu’à sa plantation en passant par sa mise en pépinière aura également animé toute l’équipe durant ces années d’exercice, afin de faire un peu plus valoir ses multiples intérêts et susciter les efforts de gestion, de conservation et de reboisement. [less ▲]Detailed reference viewed: 15 (0 ULg) Ceci n’est pas un conseil !Choffray, Jean-Marie E-print/Working paper (2015)La « Grande Récession de 2008 » a un mérite. Un seul ! Elle a rendu public le fait que personne ne savait exactement ce qui s’était passé, ni ce qui se passait. Pourquoi une telle crise de confiance avait ... [more ▼]La « Grande Récession de 2008 » a un mérite. Un seul ! Elle a rendu public le fait que personne ne savait exactement ce qui s’était passé, ni ce qui se passait. Pourquoi une telle crise de confiance avait-elle vu le jour ? Quelles en seraient les conséquences ? Toutes et tous se sont trompés, y compris les meilleurs. Même celles et ceux qui étaient convaincus d’avoir raison ! Plus que jamais, l’incertitude, la saine et souveraine incertitude, garantit la liberté de l’investisseur... et du professeur ! [less ▲]Detailed reference viewed: 1144 (87 ULg) La culture dans l'agenda post-2015: de la mobilisation internationale à l'inclusion modeste?Vlassis, Antonios E-print/Working paper (2015)Detailed reference viewed: 11 (1 ULg) Some misunderstood or unknown tricks (XIII) (LaTeX)Merciadri, Luca E-print/Working paper (2015)We will here again consider many tips and tricks. This time, they will mostly come from Glad Deschrijver, TeX Tricks, 2011. (http://users.ugent.be/~gdschrij/LaTeX/textricks.html.) Tricks: vertically ... [more ▼]We will here again consider many tips and tricks. This time, they will mostly come from Glad Deschrijver, TeX Tricks, 2011. (http://users.ugent.be/~gdschrij/LaTeX/textricks.html.) Tricks: vertically aligned itemize environments, allowing linebreaks after comma in math mode, writing under and over elements, and using stacks, footnotes with a new number at each section, footnotes in tabular, splitting algorithm environments on multiple pages, let " produce opening/closing quotation marks, indenting some text but not the first line, using diagonal dots positioned according to the opposite diagonal, using a centered verbatim environment, drawing a table with dashed lines, shaded cells and arrows pointing at a row and a column, correct spacing around square brackets (used for sets) in math mode. [less ▲]Detailed reference viewed: 2 (1 ULg) Some misunderstood or unknown LaTeX tricks (XIV) and LaTeX learning curveMerciadri, Luca E-print/Working paper (2015)We will here give three tricks: i. using a personalized \overline, ii. boxing every digit of an integer, iii. using \scalebox. I will then expose my point of view about the LaTeX learning curve, and give ... [more ▼]We will here give three tricks: i. using a personalized \overline, ii. boxing every digit of an integer, iii. using \scalebox. I will then expose my point of view about the LaTeX learning curve, and give some of the most common beginners’ mistakes. [less ▲] Some misunderstood or unknown LaTeX tricks (XV)Merciadri, Luca E-print/Working paper (2015)After having looked at about 150 StackExchange pages of 50 topics (that sums up to about 7500 topics’ names), I give you, in this article and in the next issue, the most interesting topics’ answers to my ... [more ▼]After having looked at about 150 StackExchange pages of 50 topics (that sums up to about 7500 topics’ names), I give you, in this article and in the next issue, the most interesting topics’ answers to my eyes. We will first begin by two additions in regard to 31(3), 32(1). [less ▲]Detailed reference viewed: 19 (0 ULg) Some misunderstood or unknown LaTeX tricks (XVI)Merciadri, Luca E-print/Working paper (2015)This is the second (and last) part of the tricks I found on StackExchange. First part began in the preceding issue. We will begin by a personal trick, and end by some inquiry about my LaTeX Tips & Tricks.Detailed reference viewed: 12 (2 ULg) Importance et rôle de l’investissement…Choffray, Jean-Marie E-print/Working paper (2015)Quelques observations et réflexions en réponse à une question qui m’est souvent posée sur l’importance et le rôle des investisseurs. Ces « Charognards », particulièrement visés au cours des périodes de ... [more ▼]Quelques observations et réflexions en réponse à une question qui m’est souvent posée sur l’importance et le rôle des investisseurs. Ces « Charognards », particulièrement visés au cours des périodes de tension géopolitique, de populisme ou de débauche monétaire, semblables à celle que nous vivons aujourd’hui. Ma réponse en peu de mots : les investisseurs sont des défenseurs de la valeur du travail par temps calme et des vigies dans la tempête ! [less ▲]Detailed reference viewed: 84 (12 ULg) La Porte Mantile et la Porte du Capitole [de la cathédrale de Tournai] dans l'Histoire de l'Art romanVan den Bossche, Benoît E-print/Working paper (2015)Detailed reference viewed: 26 (6 ULg) Documents as a source of information; Tabular packages' purposes, conflicts; Same space in matrices; Logic inferencesMerciadri, Luca E-print/Working paper (2015)The various aspects of the title are considered.Detailed reference viewed: 32 (16 ULg) Some misunderstood or unknown tricks (X) (LaTeX)Merciadri, Luca E-print/Working paper (2015)This is the 10th edition of my Tips & Tricks.' This time, we shall first see how to write dancing text,' roman numerals, how to draw under and over braces on same elements, and how to display aligned ... [more ▼]This is the 10th edition of my Tips & Tricks.' This time, we shall first see how to write dancing text,' roman numerals, how to draw under and over braces on same elements, and how to display aligned (in)equations systems. We will then end by discussing on BibLaTeX and Biber, which constitute a promising alternative to BibTeX. [less ▲]Detailed reference viewed: 4 (2 ULg) Some misunderstood or unknown tricks (XI) (LaTeX) and encoding issues (II)Merciadri, Luca E-print/Working paper (2015)Three subjects will be detailed: 1. Using LaTeX syntax as an unambiguous way to communicate, 2. Writing a bold \ell, 3. Fonts' encodings.Detailed reference viewed: 1 (1 ULg) Entretien avec Kathryn BatchelorOumarou Mal Mazou, Rachid E-print/Working paper (2015)Detailed reference viewed: 18 (8 ULg) A branch-and-price algorithm for 2-period vehicle routing problemsCrama, Yves ; Rezaei Sadrabadi, Mahmood ; Van Woensel, TomE-print/Working paper (2015)We consider a Vehicle Routing Problem (VRP) with deterministic orders in two periods from a set of stores. Orders in period 1 (2) can be postponed (advanced) to the other period but any diversion from the ... [more ▼]We consider a Vehicle Routing Problem (VRP) with deterministic orders in two periods from a set of stores. Orders in period 1 (2) can be postponed (advanced) to the other period but any diversion from the initial orders incurs a penalty. From the perspective of a Logistics Service Provider (LSP), such diversions could be beneficial if savings in the routing costs outweigh the penalties. So could they be from a store's view, as the store can set a high enough penalty to compensate the diversion from its own optimal orders. In this paper, we introduce a new model where we seek a better solution for the LSP, compared to solving two independent VRPs with fixed orders, by allowing orders to be fully postponed or advanced. We apply a branch-and-price algorithm to solve this model to optimality. Many cutting-edge techniques are implemented to have an efficient branch-and-price algorithm, and two ideas to possibly improve the upper bound are tested. We draw algorithmic and managerial insights based on our test instances. [less ▲]Detailed reference viewed: 49 (2 ULg) Investing in the FuturePahud de Mortanges, Charles E-print/Working paper (2015)This paper attempts to address the challenges of how to invest in Synthetic Biology firms, most of which are relatively new start-ups and unprofitable. Valuing an early-stage firm with only a brief ... [more ▼]This paper attempts to address the challenges of how to invest in Synthetic Biology firms, most of which are relatively new start-ups and unprofitable. Valuing an early-stage firm with only a brief operating history, little or no operating profit (or even revenue), and an immature and untested business model, could be a formidable challenge. We propose a limited number of quantitative, and a larger number of qualitative criteria. An investor may consider these when faced with analyzing a new untried business, but one he/she believes has considerable potential for success in the future. [less ▲]Detailed reference viewed: 29 (1 ULg) Lacunary wavelet series on Cantor setsEsser, Céline E-print/Working paper (2015)We construct functions with prescribed multifractal spectra which satisfy the leaders profile method.Detailed reference viewed: 3 (0 ULg) Topology on new sequence spaces defined with wavelet leadersBastin, Françoise ; Esser, Céline ; Simons, Laurent E-print/Working paper (2015)Using wavelet leaders instead of wavelet coefficients, new sequence spaces of type Sν are defined and endowed with a natural topology. Some classical topological properties are then studied; in particular ... [more ▼]Using wavelet leaders instead of wavelet coefficients, new sequence spaces of type Sν are defined and endowed with a natural topology. Some classical topological properties are then studied; in particular, a generic result about the asymptotic repartition of the wavelet leaders of a sequence in Lν is obtained. Eventually, comparisons and links with Oscillation spaces are also presented as well as with Sν spaces. [less ▲]Detailed reference viewed: 9 (2 ULg) Sequential testing of k-out-of-n systems with imperfect testsWenchao, Wei; Coolen, Kris ; Talla Nobibon, Fabrice et alE-print/Working paper (2015)A k-out-of-n system configuration requires that, for the overall system to be functional, at least k out of the total of n components be working. We consider the problem of sequentially testing the ... [more ▼]A k-out-of-n system configuration requires that, for the overall system to be functional, at least k out of the total of n components be working. We consider the problem of sequentially testing the components of a k-out-of-n system in order to learn the state of the system, when the tests are costly and when the individual component tests are imperfect, which means that a test can identify a component as working when in reality it is down, and vice versa. Each component is tested at most once. Since tests are imperfect, even when all components are tested the state of the system is not necessarily known with certainty, and so reaching a lower bound on the probability of correctness of the system state is used as a stopping criterion for the inspection. We define different classes of inspection policies and we examine global optimality of each of the classes. We find that a globally optimal policy for diagnosing k-out-of-n systems with imperfect tests can be found in polynomial time when the predictive error probabilities are the same for all the components. Of the three policy classes studied, the dominant policies always contain a global optimum, while elementary policies are compact in representation. The newly introduced class of so-called `interrupted block-walking' policies combines these merits of global optimality and of compactness. [less ▲]Detailed reference viewed: 14 (1 ULg) Policy dialogue: What it is and how it can contribute to evidence-informed decision-making.Rajan, D; El Husseiny, D; Porignon, Denis et alE-print/Working paper (2015)Detailed reference viewed: 13 (0 ULg) Towards generic image classification: an extensive empirical studyMarée, Raphaël ; Geurts, Pierre ; Wehenkel, Louis E-print/Working paper (2014)This paper considers the general problem of image classification without using any prior knowledge about image classes. We study variants of a method based on supervised learning whose common steps are ... [more ▼]This paper considers the general problem of image classification without using any prior knowledge about image classes. We study variants of a method based on supervised learning whose common steps are the extraction of random subwindows described by raw pixel intensity values and the use of ensemble of extremely randomized trees to directly classify images or to learn image features. The influence of method parameters and variants is thoroughly evaluated so as to provide baselines and guidelines for future studies. Detailed results are provided on 80 publicly available datasets that depict very diverse types of images (more than 3800 image classes and over 1.5 million images). [less ▲]Detailed reference viewed: 58 (2 ULg) Detection of local outliers in spatial multivariate dataErnst, Marie ; Haesbroeck, Gentiane E-print/Working paper (2014)Outlier detection techniques in spatial data should allow to identify two types of outliers: global and local ones. Local outliers typically have non-spatial attributes that strongly differ from those ... [more ▼]Outlier detection techniques in spatial data should allow to identify two types of outliers: global and local ones. Local outliers typically have non-spatial attributes that strongly differ from those observed on their neighbors. Detecting local outliers requires to be able to work locally, on neighborhoods, in order to take into account the spatial dependence between the statistical units under consideration, even though the outlyingness is usually measured on the non-spatial variables. Many procedures have been outlined in the literature, but their number reduces when one wants to deal with multivariate non-spatial attributes. In this paper, focus is on the multivariate context. A review of existing procedures is done. A new approach, based on a two-step improvement of an existing one, is also designed and compared with the benchmarked methods by means of examples and simulations. [less ▲]Detailed reference viewed: 14 (7 ULg) Lettre d'information du projet Dacefi-Synthèse & réalisations majeuresMeunier, Quentin; Morin, Amélie; Moumbougou, Carl et alE-print/Working paper (2014)Cette dernière lettre d'information du projet présente le bilan de ses réalisations et les avancées importantes du Gabon en termes de foresterie communautaireDetailed reference viewed: 116 (66 ULg) Projet DACEFI 2. Principes fondateurs d'une forêt communautaire au Gabon. Outils de vulgarisation et de sensibilisation.Meunier, Quentin; Boldrini, Sylvie; Larzillière, Adélaïde et alE-print/Working paper (2014)Faisant suite à une première phase (2006-2008), le projet pilote Développement d’Alternatives Communautaires à l’Exploitation Forestière Illégale (DACEFI-2, de 2010 à 2014) s’emploie à tester au Gabon la ... [more ▼]Faisant suite à une première phase (2006-2008), le projet pilote Développement d’Alternatives Communautaires à l’Exploitation Forestière Illégale (DACEFI-2, de 2010 à 2014) s’emploie à tester au Gabon la mise en oeuvre des premières forêts communautaires. Un de ses objectifs majeurs consiste à tester le concept de foresterie communautaire au sein de plusieurs sites partenaires et de témoigner de l’expérience acquise afin que le Ministère en charge des Forêts adapte le cadre réglementaire. Quatre textes majeurs régissent la foresterie communautaire au Gabon, une loi (n°16/01), un décret d’application (n°1028/PR/MEFEPEPEN) et deux arrêtés (n°018/MEF/SG/DGF/DFC et n°106/MEFEPRN). Ils encadrent le processus de création d’une forêt communautaire. Afin de les rendre accessibles à un plus grand nombre, le projet DACEFI-2 s’est proposé de développer plusieurs supports de vulgarisation à destination des agents des Eaux et Forêts et des villageois. En éditant et en diffusant une série de posters, de films ou encore de bandes dessinées, le projet a contribué à faire connaître dans les provinces de l’Ogooué-Ivindo et du Moyen-Ogooué, l’esprit de ces textes légaux qui visent à favoriser le développement des communautés locales. Ce document de capitalisation présente une compilation des outils développés par les équipes du projet pour mener à bien cette campagne de sensibilisation. Nous abordons la gestion forestière durable par le prisme de la foresterie communautaire en évoquant l’esprit de la loi et les enjeux de la foresterie sociale. Nous proposons également une série de recommandations, basées sur notre expérience au Gabon, afin d’optimiser l’efficacité des communautés engagées dans ce processus. [less ▲]Detailed reference viewed: 32 (5 ULg) Aspects juridiques de la fiscalité du logement en WallonieBahi, Sacha; Bianchet, Bruno ; Farah, Jihad et alE-print/Working paper (2014)Ce numéro des « Notes de recherche » synthétise un des volets d’une étude dont l’objet est « la fiscalité relative au logement et l’aménagement du territoire ». Or, afin de bien appréhender les tenants et ... [more ▼]Ce numéro des « Notes de recherche » synthétise un des volets d’une étude dont l’objet est « la fiscalité relative au logement et l’aménagement du territoire ». Or, afin de bien appréhender les tenants et les aboutissants de cette causalité et, surtout, de formuler des recommandations et propositions relatives au système fiscal en regard d’objectifs territoriaux, une analyse approfondie du cadre juridique s’avère indispensable. Cet examen constitue, en soi, un tout cohérent auquel pourra se référer le praticien de la gestion territoriale. La présente réflexion vise ainsi à présenter les divers mécanismes juridiques qui constituent des impôts frappant les biens immobiliers affectés au logement en Wallonie. L’étude s’intéresse principalement au territoire géographique wallon et non pas au seul pouvoir taxateur : « Région wallonne ». La précision est d’importance, a fortiori depuis l’entrée en vigueur de la sixième Réforme de l’État qui élargit considérablement la compétence du législateur wallon en la matière. Sont donc traités dans ce cadre tant les impôts fédéraux que régionaux, sans oublier les diverses « taxes locales » propres à chacune des communes et provinces de Wallonie. Les impôts directs, comme les impôts indirects seront analysés. Partant de ce balayage législatif de lege lata, la réflexion s’efforce de faire ressortir les diverses nuances politiques qui se dégagent des impôts analysés. Le doigt est tantôt mis sur les lacunes légistiques des textes, tantôt sur les critiques jurisprudentielles adressées aux taxes, tantôt encore, sur les potentialités qu’offriraient la redéfinition ou le recalibrage d’un mécanisme existant. L’étude vise, lorsqu’une possibilité lui est laissée, à formuler des propositions de lege feranda afin d’affermir la légalité de certains mécanismes fiscaux et d’améliorer l’utilisation qui est faite de ceux-ci à l’heure actuelle. [less ▲]Detailed reference viewed: 59 (19 ULg) Premières mises en liberté avant jugement devant la Cour pénale internationaleDeprez, Christophe E-print/Working paper (2014)Ce billet évoque les premières libérations avant jugement intervenues devant la Cour pénale internationale (octobre 2014). Après avoir été soumis à un comité de lecture, il a été publié sur le 'blogue' de ... [more ▼]Ce billet évoque les premières libérations avant jugement intervenues devant la Cour pénale internationale (octobre 2014). Après avoir été soumis à un comité de lecture, il a été publié sur le 'blogue' de la Clinique de droit international pénal et humanitaire de l'Université de Laval. [less ▲]Detailed reference viewed: 17 (0 ULg) Corporate board attributes and conditional accounting conservatism: Evidence from French firmsBoussaid, Nabila ; Sougné, Danielle ; Hamza, TaherE-print/Working paper (2014)In this paper we investigate the relationship between boards of directors’ attributes and conditional accounting conservatism in the French context. Using a pooled regression model to evaluate this ... [more ▼]In this paper we investigate the relationship between boards of directors’ attributes and conditional accounting conservatism in the French context. Using a pooled regression model to evaluate this relationship for the period 2009-2012, our empirical results can be summarized as follows. Firstly, greater board activity encourages more conservative reporting in financial statements. Secondly, greater board size diminishes conditional accounting conservatism. Lastly, there is a positive relationship between gender diversity and conservatism. To ensure robustness we have calculated our results using alternative measures of accounting conservatism, namely time series and accrual-based measures in addition to asymmetric timeliness of earnings. These findings suggest that boards of directors’ attributes are an important factor in determining the financial reporting quality of French firms. [less ▲]Detailed reference viewed: 35 (3 ULg) Le nouveau cadre d’action en matière de climat et d’énergie à l’horizon 2030Habran, Maxime E-print/Working paper (2014)Cette note a pour but de fournir un éclairage sur le nouveau cadre d'action européen en matière de climat et d'énergieDetailed reference viewed: 22 (4 ULg) New evidence on the social security incentives as drivers of retirement behaviorJousten, Alain ; Tarantchenko, Ekaterina E-print/Working paper (2014)Detailed reference viewed: 15 (4 ULg) Illustration du rôle de la Cour constitutionnelle : si l'utilité publique n'est plus établie, les propriétaires d'un bien exproprié doivent recevoir leur bien en retourBouhon, Frédéric E-print/Working paper (2014)Les législateurs sont-ils tout puissants ? Certes ils sont à la source de l’ensemble des règles de droit dans le pays puisque ce sont eux qui adoptent les lois, les décrets et les ordonnances et que les ... [more ▼]Les législateurs sont-ils tout puissants ? Certes ils sont à la source de l’ensemble des règles de droit dans le pays puisque ce sont eux qui adoptent les lois, les décrets et les ordonnances et que les arrêtés et règlements élaborés par les gouvernements et les administrations doivent les respecter. Mais les lois, les décrets et les ordonnances doivent aussi se conformer à des règles supérieures qui s’imposent à eux, notamment à celles qui garantissent nos droits fondamentaux, et ce sous le contrôle de la Cour constitutionnelle. Un tout récent arrêt, portant le n° 132/2014 et prononcé le 25 septembre 2014 , en fournit une illustration assez simple en matière d’expropriation. [less ▲]Detailed reference viewed: 31 (0 ULg) Compte rendu de Baetens (Jan), Pour en finir avec la poésie dite minimalisteDemoulin, Laurent E-print/Working paper (2014)Il s'agit d'un compte rendu de l'ouvrage de Jan Baetens intitulé "Pour en finir avec la poésie dite minimaliste" paru sur le site Contextes à la page http://contextes.revues.org/5982.Detailed reference viewed: 17 (0 ULg) L-surface and V-valley for optimal anisotropic 2D smoothingFrasso, Gianluca ; Paul, EilersE-print/Working paper (2014)We present the L-surface as an attractive generalization of the L-curve framework for the selection of the optimal smoothing parameters in two dimensional applications. It preserves the desirable features ... [more ▼]We present the L-surface as an attractive generalization of the L-curve framework for the selection of the optimal smoothing parameters in two dimensional applications. It preserves the desirable features of its unidimensional analogous. The optimal amount of smoothing is indicated by the pair of parameters located in the point of maximum (Gaussian) curvature. Locate this point on a discrete parametric surface can be not straightforward. We introduce the V-valley as a simplified selection criterion based on distance minimization. [less ▲]Detailed reference viewed: 16 (1 ULg) Multi-period vehicle assignment problem with stochastic load availabilityCrama, Yves ; Pironet, Thierry E-print/Working paper (2014)In this research, we want to investigate optimization techniques for a generic load assignment problem including a limited fleet of vehicles within a full-truck-load (FTL) multi-period setting including ... [more ▼]In this research, we want to investigate optimization techniques for a generic load assignment problem including a limited fleet of vehicles within a full-truck-load (FTL) multi-period setting including forecasts on load availability. Several policies are generated from simple heuristics through state of the art approaches such as consensus and restricted expectation algorithms up to the optimization of a subtree of scenarios. Moreover, myopic and a-posteriori deterministic optimizations (including no or fully revealed information) set bounds for policies performance comparisons. Tests are performed for different graphs sizes and sparsity, several distribution laws and number of loads. Performances are compared statistically over paired samples. The robustness of performing policies against a false valuation of the probability distribution is also analyzed. [less ▲]Detailed reference viewed: 51 (8 ULg) Réveillez-vous, le monde vous attend…Gerkens, Jean-François ; Faymonville, Marie-Elisabeth ; Destiné, Jacques et alE-print/Working paper (2014)Par-delà le brouillard des temps présents, un message d’optimisme, de volontarisme, de foi en l’avenir et en la vie, conduisant à sept principes, ou suggestions d’action, faciles à mettre en œuvre.Detailed reference viewed: 548 (77 ULg) Estimating the out-of-sample predictive ability of trading rules: a robust bootstrap approachHambuckers, julien ; Heuchenne, Cédric E-print/Working paper (2014)In this paper, we estimate the out-of-sample predictive ability of a set of trading rules. Usually, this ability is estimated using a rolling-window sample-splitting scheme, true out-of-sample data being ... [more ▼]In this paper, we estimate the out-of-sample predictive ability of a set of trading rules. Usually, this ability is estimated using a rolling-window sample-splitting scheme, true out-of-sample data being rarely available. We argue that this method makes a poor use of the available information and creates data mining possibilities. Instead, we introduce an alternative bootstrap approach, based on the .632 bootstrap principle. This method enables to build in-sample and out-of-sample bootstrap data sets that do not overlap and exhibit the same time dependencies. We illustrate our methodology on IBM and Microsoft daily stock prices, where we compare 11 trading rules specifications. For the data sets considered, two different filter rule specifications have the highest out-of-sample mean excess returns. However, all tested rules cannot beat a simple buy-and-hold strategy when trading at a daily frequency. [less ▲]Detailed reference viewed: 38 (16 ULg) Embargo russe sur les aliments européens : l'Europe doit montrer l'exempleHabran, Maxime E-print/Working paper (2014)Cette note a pour but d’apporter des éclaircissements sur les mesures en matière de politique agricole commune prises par l’Union européenneDetailed reference viewed: 109 (7 ULg) De la crise à l’entreprise, en passant par toi…Choffray, Jean-Marie E-print/Working paper (2014)De la crise à l’entreprise, en passant par toi… est une invitation à l’action, à la prise de responsabilité, à la création responsable de valeur économique et à la recherche obstinée de croissance ... [more ▼]De la crise à l’entreprise, en passant par toi… est une invitation à l’action, à la prise de responsabilité, à la création responsable de valeur économique et à la recherche obstinée de croissance rentable. Oui! Notre monde vient d’échapper à un effondrement systémique dont 1929 n’aurait constitué qu’un aimable préambule. Oui ! L’entreprise est le seul acteur social créateur de richesse économique et la seule solution au mal qui se répand. Oui ! Il est extrêmement difficile de changer quoi que ce soit sur terre et d’apprendre à dire « non ! » En cas d’échec, le coût est connu : licenciement, exil, condamnation à mort ! [less ▲]Detailed reference viewed: 413 (55 ULg) Inventaire des incunables de la Bibliothèque universitaire Moretus Plantin et du Centre de Documentation et de Recherche Religieuses de NamurAdam, Renaud E-print/Working paper (2014)Detailed reference viewed: 21 (2 ULg) Bonaventure, S., Meditationes vitae Christi, Paris : [Pierre Le Dru], pour Jean Petit, [ca 1497], 8°Adam, Renaud E-print/Working paper (2014)Detailed reference viewed: 23 (1 ULg) Lettre d'information trimestrielle n° 15 du projet DACEFI 2Boldrini, Sylvie; Meunier, Quentin; Moumbogou, Carl et alE-print/Working paper (2014)Detailed reference viewed: 11 (0 ULg) Towards a system of concept in GP/FM. Part I towards a specific indexation system. working draftJamoulle, Marc E-print/Working paper (2014)EXECUTIVE SUMMARY Towards a system of concept on general practice / family medicine Part 1 Towards a specific indexation system in GP/FM Status of this document ; preliminary draft, not for diffusion ... [more ▼]EXECUTIVE SUMMARY Towards a system of concept on general practice / family medicine Part 1 Towards a specific indexation system in GP/FM Status of this document ; preliminary draft, not for diffusion Intended audience : Members of the board of the PhD thesis of Marc Jamoulle, department of general practice, Liege University and experts in the field contacted by the author Background :Thousands of general practitioners/ family doctors are gathering each year in local, national or international congresses. They are exchanging thoughts, researches and methods through thousands of communications in various formats; posters, oral communications, workshops and so on. Although this huge collection of bottom-up knowledge is sometimes available through Internet sites, there is no specific indexation system allowing a real knowledge management of the exposed works. Consequently the information could not be reached, which don’t favor the exchange between researchers. The absence of a common indexation system is also a problem to organize the congresses and the participants have always difficulties to find communications relevant of their interest. The technology of semantic web and Linked data have emerged as a future solution to exchange data distributed in many languages between so many providers, the family physicians, spread around the globe. The considerable development of medical ontologies demonstrates the vitality of this field of discovery. Aim of the thesis; To find the best way to identify the main concepts effectively used by practicing GPs by the development of a system of classification embedded in the International classification of Primary Care aiming at retrieval of clinical and non-clinical issues addressed by the authors in their communications To propose a mapped terminology to this classification systems, in other words an ontology of GP/FM, to participle to a linked data based automatic or semi-automatic indexation of knowledge in GP/FM and its implementation in the realm of the semantic web. Content of the part 1 : the first steps towards a global classification system in GP/FM are related as well as previous experiences and difficulties with usual coding systems. The new information technology tools for information management are concisely described which permit the understanding of their importance in future research networks of knowledge in G/FM A comparison of the coding process and results of 6 congress of GP/FM in several countries and 4 languages has been performed to examine the internal reproducibility of the classifying system proposed. Next steps of the thesis are discussed of which first of them would be the constitution of an International research group. [less ▲]Detailed reference viewed: 10 (0 ULg) Retrouvailles à vélo avec Dick AnnegarnDemoulin, Laurent E-print/Working paper (2014)Le nouveau CD de Dick Annegarn, Vélo va (2014), offre à son auditeur, à travers un bel échantillon de dix chansons, un aperçu des différentes facettes de l’art de l’auteur-compositeur-interprète.Detailed reference viewed: 11 (2 ULg) Some misunderstood or unknown tricks (IX) (LaTeX)Merciadri, Luca E-print/Working paper (2014)We describe here how to display date & time in a standard format, write (draw) dash integrals, number rows in tables, use unhabitual punctuation marks: interrobang and percontation point, draw dependency ... [more ▼]We describe here how to display date & time in a standard format, write (draw) dash integrals, number rows in tables, use unhabitual punctuation marks: interrobang and percontation point, draw dependency arrows, distinguish between ConTeXt, LuaTeX, teTeX and XeTeX. The last section gives a LaTeX-related crossword puzzle. [less ▲]Detailed reference viewed: 50 (22 ULg) Presidential election in Turkey: a wide range of intricate challenges ahead of the next presidentSisu, Madalina; Lika, Liridon E-print/Working paper (2014)On 10 August 2014, Turkey will hold the first round of presidential election which are of specific importance, as its results will shape the country’s both domestic politics and external relations. This ... [more ▼]On 10 August 2014, Turkey will hold the first round of presidential election which are of specific importance, as its results will shape the country’s both domestic politics and external relations. This paper discusses the key challenges which Turkey’s next president must undertake. The domestic challenges range from revision of Constitution, Kurdish peace process and economic growth to polarization of society, freedom of judiciary, separation of powers and civil liberties. In the external relations area, the principal challenges are the worsening of country’s relations with its neighbours, security threats and the stalemate of the EU integration. Several domestic and external challenges are inter-related: for instance, the freedom of judiciary, separation of powers and civil liberties affect the EU integration process; the political uncertainty relates to economic growth and foreign investments; the Kurdish peace process impacts on the external security issues; the economic factors influence the relations with the Kurdistan Regional Government and Iraq’s central government; the Syrian crisis raises new challenges with regard to the Syrian refugees in Turkey. Therefore, addressing Turkey’s current domestic and external challenges will be a long, puzzling and often conflicting-results process. [less ▲]Detailed reference viewed: 18 (1 ULg) Recueil de réglementation interne des principaux partis allemands, belges et britanniquesBouhon, Frédéric E-print/Working paper (2014)Le présent recueil compile des extraits de la réglementation interne des principaux partis allemands, belges et britanniques. Cette documentation vient principalement appuyer le chapitre 1er de la ... [more ▼]Le présent recueil compile des extraits de la réglementation interne des principaux partis allemands, belges et britanniques. Cette documentation vient principalement appuyer le chapitre 1er de la deuxième partie de notre étude sur le droit électoral et le principe d’égalité (à paraître en septembre 2014 aux éditions Bruylant) dans laquelle nous avons notamment étudié une partie du droit interne de certaines formations politiques. [less ▲]Detailed reference viewed: 35 (7 ULg) En attendant ToussaintDemoulin, Laurent E-print/Working paper (2014)Présentation et analyse de deux courtes pièces, Rideau et Ni l'un ni l'autre, écrites par Jean-Philippe Toussaint en 1981, quand il était un jeune auteur inconnu influencé par Samuel Beckett.Detailed reference viewed: 25 (4 ULg) Hartman Schedel, Liber Chronicarum, Nuremberg : Anton Koberger, pour Sebald Schreyer et Sebastian Kammermeister, 12 juillet 1493, 2°Adam, Renaud E-print/Working paper (2014)Detailed reference viewed: 27 (1 ULg) Short Prime Quadratizations of Cubic Negative MonomialsCrama, Yves ; Rodriguez Heck, Elisabeth E-print/Working paper (2014)Pseudo-Boolean functions naturally model problems in a number of different areas such as computer science, statistics, economics, operations research or computer vision, among others. Pseudo-Boolean ... [more ▼]Pseudo-Boolean functions naturally model problems in a number of different areas such as computer science, statistics, economics, operations research or computer vision, among others. Pseudo-Boolean optimization (PBO) is NP-hard, even for quadratic polynomial objective functions. However, much progress has been done in finding exact and heuristic algorithms for the quadratic case. Quadratizations are techniques aimed at reducing a general PBO problem to a quadratic polynomial one. Quadratizing single monomials is particularly interesting because it allows quadratizing any pseudo-Boolean function by termwise quadratization. A characterization of short quadratizations for negative monomials has been provided. In this report we present a proof of this characterization for the case of cubic monomials, which requires a different analysis than the case of higher degree. [less ▲]Detailed reference viewed: 36 (17 ULg) Optimization of the service start time for an elementary shortest path problem with time windowsArda, Yasemin ; Crama, Yves ; Kucukaydin, Hande E-print/Working paper (2014)We investigate an elementary shortest path problem with resource constraints where a single capacitated vehicle, initially located at a depot, must serve a set of customers while respecting their ... [more ▼]We investigate an elementary shortest path problem with resource constraints where a single capacitated vehicle, initially located at a depot, must serve a set of customers while respecting their individual time windows. When the vehicle visits a customer, it delivers the customer's demand and collects a revenue in return for the delivery. The vehicle can start its trip at any desired time. The transportation cost is a function of both the total distance traveled and the duration of the assigned trip. The objective is to determine the service start time from the depot, the subset of customers to be served, and the trip to be performed so as to minimize the total loss, which is calculated as the di erence between the transportation cost and the revenue collected from the customers. We develop two exact dynamic programming algorithms which can deal with an in nite number of Pareto-optimal states arising from the fact that the starting time and the duration of the trip act like continuous decision variables. We report computational results obtained with these algorithms and with a faster heuristic for the elementary shortest path problem. We also examine the performance of these algorithms when they are used to solve the pricing subproblem arising in the framework of a column generation algorithm for a related vehicle routing problem with time windows. [less ▲]Detailed reference viewed: 205 (9 ULg) New Orleans Jazz & Heritage Festival 2014Sacré, Robert E-print/Working paper (2014)Compte rendu du NOLA Jazz & Heritage Festival avril-mai 2014 , avec photosDetailed reference viewed: 12 (0 ULg) China, 1978-2013: from one Plenum to another. Reflections on hopes and constraints for reform in the Xi Jingping eraFlorence, Eric E-print/Working paper (2014)Why is it so difficult to talk about China in a nuanced and contrasting manner without falling back on superlatives and generalisations? In about thirty years, China’s GDP per capita has multiplied by ... [more ▼]Why is it so difficult to talk about China in a nuanced and contrasting manner without falling back on superlatives and generalisations? In about thirty years, China’s GDP per capita has multiplied by eight. From a marginal economic power during the Maoist period (1949-1978), China is now ranked tenth in terms of global economic weight. “Wealth and power” (fu qiang) is the expression that embodies China’s quest for modernity since the second half of the 19th century, when China was still under the yoke of the West. This ambition is still at the heart of the “Chinese dream of rejuvenation of the Chinese nation” dear to Xi Jinping, which he set out during the Third Plenum of the 18th Central Committee of the Chinese Communist Party. But focusing only on this vision of “wealth and power” takes us back to one of the most common ways of representing China: reducing the ongoing socio-economic changes and dynamics to a set of numeric values, ultimately reified and homogenised. The increased power and internationalisation of the Chinese economy has prompted a combination of worry and enthusiasm. What does this imply about the paradigm shift in the way we portray this country? Perhaps it is still hard to leave behind the image of a subordinate, poor and voiceless China and consider the Chinese people as, at least, our equals. [less ▲]Detailed reference viewed: 59 (0 ULg) L’Université de Liège pendant la guerre 1914-1918Bechet, Christophe E-print/Working paper (2014)Histoire de l'Université de Liège pendant la Grande Guerre, axée principalement sur le drame de la place du 20 août et l'occupation des locaux par l'armée allemande.Detailed reference viewed: 25 (4 ULg) Fonck meurt premier comme devantBechet, Christophe E-print/Working paper (2014)Cet article revient sur le mythe du cavalier Fonck, premier soldat belge tué le 4 août 1914, sur la route Thimister-BatticeDetailed reference viewed: 7 (0 ULg) Half a century of French organizational sociology: methodological roots, compositionist branchesDubois, Christophe E-print/Working paper (2014)Now that 50 years have gone by since the publication of The Bureaucratic Phenomenon (French title: Le phénomène bureaucratique, 1963) by Michel Crozier, what is the legacy bequeathed by the sociology of ... [more ▼]Now that 50 years have gone by since the publication of The Bureaucratic Phenomenon (French title: Le phénomène bureaucratique, 1963) by Michel Crozier, what is the legacy bequeathed by the sociology of organizations, in France and elsewhere, to today’s researchers? This contribution considers the premises of this methodology in order to establish two important achievements: the “decomposition” of the notions of organization, State and market; and the distinction of three dimensions of organizations, i.e. their managerial discourse, formal and informal structures. This article ends by considering one contemporary challenge this tradition of research has to face: how to account for the mechanisms of collective action, in order to take part in its composition? [less ▲]Detailed reference viewed: 21 (7 ULg) Les parlements peuvent-ils encore valider les pouvoirs de leurs élus?Bouhon, Frédéric E-print/Working paper (2014)Les élections du 25 mai 2014 ont été suivies de diverses contestations sur certains aspects de leur déroulement, spécialement au stade de leur dépouillement. C'est l'occasion de faire le point sur la ... [more ▼]Les élections du 25 mai 2014 ont été suivies de diverses contestations sur certains aspects de leur déroulement, spécialement au stade de leur dépouillement. C'est l'occasion de faire le point sur la prérogative des assemblées législatives belges de vérifier elles-mêmes la validité des pouvoirs de leurs membres. [less ▲]Detailed reference viewed: 8 (2 ULg) The binary near-Earth asteroid (175706) 1996 FG3 - An observational constraint on its orbital stabilityScheirich, P.; Pravec, P.; Jacobson, S. A. et alE-print/Working paper (2014)Using our photometric observations taken between April 1996 and January 2013 and other published data, we derive properties of the binary near-Earth asteroid (175706) 1996 FG3 including new measurements ... [more ▼]Using our photometric observations taken between April 1996 and January 2013 and other published data, we derive properties of the binary near-Earth asteroid (175706) 1996 FG3 including new measurements constraining evolution of the mutual orbit with potential consequences for the entire binary asteroid population. We also refined previously determined values of parameters of both components, making 1996 FG3 one of the most well understood binary asteroid systems. We determined the orbital vector with a substantially greater accuracy than before and we also placed constraints on a stability of the orbit. Specifically, the ecliptic longitude and latitude of the orbital pole are 266{\deg} and -83{\deg}, respectively, with the mean radius of the uncertainty area of 4{\deg}, and the orbital period is 16.1508 +\- 0.0002 h (all uncertainties correspond to 3sigma). We looked for a quadratic drift of the mean anomaly of the satellite and obtained a value of 0.04 +\- 0.20 deg/yr^2, i.e., consistent with zero. The drift is substantially lower than predicted by the pure binary YORP (BYORP) theory of McMahon and Scheeres (McMahon, J., Scheeres, D. [2010]. Icarus 209, 494-509) and it is consistent with the theory of an equilibrium between BYORP and tidal torques for synchronous binary asteroids as proposed by Jacobson and Scheeres (Jacobson, S.A., Scheeres, D. [2011]. ApJ Letters, 736, L19). Based on the assumption of equilibrium, we derived a ratio of the quality factor and tidal Love number of Q/k = 2.4 x 10^5 uncertain by a factor of five. We also derived a product of the rigidity and quality factor of mu Q = 1.3 x 10^7 Pa using the theory that assumes an elastic response of the asteroid material to the tidal forces. This very low value indicates that the primary of 1996 FG3 is a 'rubble pile', and it also calls for a re-thinking of the tidal energy dissipation in close asteroid binary systems. [less ▲]Detailed reference viewed: 14 (2 ULg) Federico García Lorca en LiejaFrancois, Jeromine E-print/Working paper (2014)Detailed reference viewed: 10 (0 ULg) Bernard de Clairvaux, S., Opuscula, [Cologne : Imprimeur du 'Dialogus Salomonis et Marcolfi' (Ludwig von Renchen ?), avant le 6 mai 1478], 2°Adam, Renaud E-print/Working paper (2014)Detailed reference viewed: 15 (2 ULg) Lettre d'information trimestrielle n° 14 du projet DACEFI 2Meunier, Quentin; Moumbogou, Carl; Boldrini, Sylvie et alE-print/Working paper (2014)Detailed reference viewed: 15 (3 ULg) Distribution under elliptical symmetry of a distance-based multivariate coefficient of variationAerts, Stéphanie ; Haesbroeck, Gentiane ; Ruwet, Christel E-print/Working paper (2014)Detailed reference viewed: 45 (20 ULg) The Macroeconomics of PAYG Pension Schemes in an Aging SocietyArtige, Lionel ; Cavenaile, Laurent; Pestieau, Pierre E-print/Working paper (2014)Detailed reference viewed: 21 (0 ULg) Some misunderstood or unknown tricks (VIII) and Turing-completeness (LaTeX)Merciadri, Luca E-print/Working paper (2014)We will begin by exposing new tricks, i.e. how to 1. write ‘closed’ square roots, 2. insert blank pages, 3. ask the reader to turn the page, 4. write bold words in an index, 5. divide a cell by a diagonal ... [more ▼]We will begin by exposing new tricks, i.e. how to 1. write ‘closed’ square roots, 2. insert blank pages, 3. ask the reader to turn the page, 4. write bold words in an index, 5. divide a cell by a diagonal, 6. draw ‘product integrals,’ 7. understand what happens when \mathcal has a lower-case letter argument. We will then consider an uncommon example of what one can do with LaTeX, in link with its Turing completeness. [less ▲]Detailed reference viewed: 60 (20 ULg) An Ant Colony System for Responsive Dynamic Vehicle RoutingSchyns, Michael E-print/Working paper (2014)We present an algorithm based on an Ant Colony System to deal with a broad range of Dynamic Capacitated Vehicle Routing Problems with Time Windows, (partial) Split Delivery and Heterogeneous fleets ... [more ▼]We present an algorithm based on an Ant Colony System to deal with a broad range of Dynamic Capacitated Vehicle Routing Problems with Time Windows, (partial) Split Delivery and Heterogeneous fleets (DVRPTWSD). Besides the traditional distance criterion, we address the important case of responsiveness. Responsiveness is defined here as completing a delivery as soon as possible, within the time window, such that the client or the truck may restart its activities. This is crucial for many production or service activities in different fields: express parcel deliveries, taxi services, Just in Time production, express repair services, medical care, petrol station replenishment, etc. We develop an interactive web-based solution to allow dispatchers to take new information into account in real-time. The algorithm and its parametrization were tested on real and artificial instances. We first illustrate our approach with a problem submitted by Liege Airport, the 8th biggest cargo airport in Europe. The goal is to develop a decision system to optimize the journey of the refueling trucks. We then consider some classical VRP benchmarks with extensions for more complex problems. [less ▲]Detailed reference viewed: 66 (18 ULg) HexisDurand, Pascal E-print/Working paper (2014)Définition et discussion du concept d'« Hexis » dans la sociologie de Pierre Bourdieu.Detailed reference viewed: 55 (14 ULg) IllusioDurand, Pascal E-print/Working paper (2014)Définition et discussion du concept d'« Illusio » dans la sociologie de Pierre Bourdieu.Detailed reference viewed: 49 (20 ULg) Capital symboliqueDurand, Pascal E-print/Working paper (2014)Présentation et discussion du concept de « Capital symbolique » dans la sociologie de Pierre Bourdieu.Detailed reference viewed: 77 (15 ULg) Protecting Assets Under Non-Parametric Market ConditionsChoffray, Jean-Marie ; Pahud de Mortanges, Charles E-print/Working paper (2014)Under non-parametric market conditions, investors usually become more concerned about the return of their money than about the return on their money. Protecting assets becomes the surest if not the only ... [more ▼]Under non-parametric market conditions, investors usually become more concerned about the return of their money than about the return on their money. Protecting assets becomes the surest if not the only path to survival and growth. High frequency trading systems, over leveraged shadow entities, flash crashes, and stealth central bank actions, to name a few, contribute to create a “Rumsfeldian” type of world in which decision makers have to cope not only with “Known knowns” – things they know that they know – but also with “Unknown unknowns” – things they don’t know that they don’t know! The goal of this paper is to explore such a conceptual model of the “Unknown” and to derive from it a concise and coherent set of battle-tested heuristics aimed at designing effective investment strategies to protect assets. [less ▲]Detailed reference viewed: 355 (36 ULg) A new methodological approach for error distributions selection in FinanceHambuckers, julien ; Heuchenne, Cédric E-print/Working paper (2014)In this article, we propose a robust methodology to select the most appropriate error distribution candidate, in a classical multiplicative heteroscedastic model. In a first step, unlike to the ... [more ▼]In this article, we propose a robust methodology to select the most appropriate error distribution candidate, in a classical multiplicative heteroscedastic model. In a first step, unlike to the traditional approach, we don't use any GARCH-type estimation of the conditional variance. Instead, we propose to use a recently developed nonparametric procedure (Mercurio and Spokoiny, 2004): the Local Adaptive Volatility Estimation (LAVE). The motivation for using this method is to avoid a possible model misspecification for the conditional variance. In a second step, we suggest a set of estimation and model selection procedures (Berk-Jones tests, kernel density-based selection, censored likelihood score, coverage probability) based on the so-obtained residuals. These methods enable to assess the global fit of a given distribution as well as to focus on its behavior in the tails. Finally, we illustrate our methodology on three time series (UBS stock returns, BOVESPA returns and EUR/USD exchange rates). [less ▲]Detailed reference viewed: 52 (23 ULg) Les determinants des Price-Earnings ratios en EuropeLambert, Marie ; Lenglois, Julien ; Streel, Alexandre et alE-print/Working paper (2014)Méthode largement employée en matière d’évaluation d’entreprise, l’analyse dite comparative s’appuie sur une estimation de la valeur des entreprises selon un multiple de leur agrégat financier. Aussi ... [more ▼]Méthode largement employée en matière d’évaluation d’entreprise, l’analyse dite comparative s’appuie sur une estimation de la valeur des entreprises selon un multiple de leur agrégat financier. Aussi appelée ‘méthode des pairs’, les multiples sont définis sur base d’un échantillon d’entreprises considérées comme comparable en termes de croissance et de risque. Le secteur est généralement retenu en pratique comme critère sous-tendant la croissance et le profil de risque opérationnel de l’entreprise. L’analyse menée dans cet article démontre l’importance des fondamentaux tels que la croissance, le risque et le taux de distribution des bénéfices dans la définition des pairs et donc de la valeur des entreprises. Sur base d’un échantillon des 100 entreprises cotées sur l’EURONEXT, entreprises les plus capitalisées et liquides, l’étude met en évidence un impact différencié de ces déterminants selon les conditions économiques. Les conséquences de notre analyse sont multiples. Premièrement, notre étude témoigne de l’importance des variables telles que le profil de risque et les perspectives croissance pour la sélection des pairs. Notre approche permet par ailleurs d’appréhender la valeur des entreprises sur base de leurs propres fondamentaux, corrigeant ainsi la méthode des multiples ‘sectoriels’ pour les différences qui subsistent au sein des sous-jacents de la valeur. Finalement, cet article nourrit une discussion quant à l’impact de la finance comportementale sur la valorisation de l’entreprise de par l’impact différencié des fondamentaux sur la valeur des entreprises au cours du temps. [less ▲]Detailed reference viewed: 55 (9 ULg) Guillaume Durand, Rationale divinorum officiorum (éd. Johannes Aloisius Tuscanus), Vicence : Hermannus Liechtenstein, 1480, 2°Adam, Renaud E-print/Working paper (2014)Detailed reference viewed: 29 (4 ULg) Estimation and approximation in nonlinear dynamic systems using quasilinearizationFrasso, Gianluca ; Jaeger, Jonathan ; Lambert, Philippe E-print/Working paper (2014)Nonlinear (systems of) ordinary differential equations (ODEs) are common tools in the analysis of complex one-dimensional dynamic systems. In this paper we propose a smoothing approach regularized by a ... [more ▼]Nonlinear (systems of) ordinary differential equations (ODEs) are common tools in the analysis of complex one-dimensional dynamic systems. In this paper we propose a smoothing approach regularized by a quasilinearized ODE-based penalty in order to approximate the state functions and estimate the parameters defining nonlinear differential systems from noisy data. Within the quasilinearized spline based framework, the estimation process reduces to a conditionally linear problem for the optimization of the spline coefficients. Furthermore, standard ODE compliance parameter(s) selection criteria are easily applicable and conditions on the state function(s) can be eventually imposed using soft or hard constraints. The approach is illustrated on real and simulated data. [less ▲]Detailed reference viewed: 15 (6 ULg) Tentatives de réflexion sémiotique et psychanalytique au sujet du voile islamiqueDemoulin, Laurent E-print/Working paper (2014)La sémiotique et la psychanalyse sont peut-être de nature à enrichir le débat sur l'interdiction du voile islamique dans les lieux publics.Detailed reference viewed: 27 (4 ULg) Classifying pairs with trees for supervised biological network inferenceSchrynemackers, Marie ; Wehenkel, Louis ; Madan Babu, Mohan et alE-print/Working paper (2014)Detailed reference viewed: 34 (11 ULg) Le Parti Socialiste en 2014: un programme électoral en rupture avec les précédents ?Piet, Grégory ; Dandoy, RégisE-print/Working paper (2014)Detailed reference viewed: 19 (3 ULg) Multivariate coefficients of variation: comparison and influence functionsAerts, Stéphanie ; Haesbroeck, Gentiane ; Ruwet, Christel E-print/Working paper (2014)In the univariate setting, coeﬃcients of variation are well known and used to compare the variability of populations characterized by variables expressed in diﬀerent units or having really diﬀerent means ... [more ▼]In the univariate setting, coeﬃcients of variation are well known and used to compare the variability of populations characterized by variables expressed in diﬀerent units or having really diﬀerent means. When dealing with more than one variable, the use of such a relative dispersion measure is much less common even though several generalizations of the coeﬃcient of variation to the multivariate setting have been introduced in the literature. In this paper, the lack of robustness of the sample versions of the multivariate coeﬃcients of variation (MCV) is illustrated by means of inﬂuence functions and some robust counterparts based either on the Minimum Covariance Determinant (MCD) estimator or on the S estimator are advocated. Then, focusing on two of the considered MCV’s, a diagnostic tool based on their inﬂuence functions is derived and its eﬃciency in detecting observations having an unduly large eﬀect on variability is illustrated on a real-life data set. The inﬂuence functions are also used to compute asymptotic variances under elliptical distributions, yielding approximate conﬁdence intervals. Finally, simulations are conducted in order to compare the performance of the classical and robust MCV’s in terms of variability and performance of the corresponding asymptotic conﬁdence intervals in a ﬁnite sample setting. As expected, when the data are normally distributed, the classical estimator performs better than the robust counterparts based on the MCD or S estimator, while the reverse is true when the data are contaminated. [less ▲]Detailed reference viewed: 38 (11 ULg) Répertoires des ouvrages du XVIe et du XVIIe siècle de la Bibliothèque universitaire Plantin Moretus et du Centre de Documentation et de Recherche Religieuses de Namur par le Père Charles MatagneAdam, Renaud E-print/Working paper (2014)Detailed reference viewed: 15 (3 ULg) Examining the Effect of Earnings Management on Bid-Ask Spread and Market LiquiditySougné, Danielle ; Ajina, Aymen E-print/Working paper (2014)The main purpose of this paper is to argue the extent that earnings management lowers liquidity. It should increase information asymmetry and impair trading liquidity. Using a sample of French firms from ... [more ▼]The main purpose of this paper is to argue the extent that earnings management lowers liquidity. It should increase information asymmetry and impair trading liquidity. Using a sample of French firms from 2008 to 2011, we find that firms that manage earnings have wider bid-ask spreads. Our results are robust for both of two well established measures of market liquidity. Therefore the empirical results indicate that firms that exhibit greater earnings management are associated with lower market liquidity. These findings are in line with adverse selection and shed light on the role corporate governance devices can play in the consideration of shareholder interest’s protection, which leads to improved stock market liquidity levels. [less ▲]Detailed reference viewed: 76 (7 ULg) Proposition de révisions de l'arrêté n° 018/MEF/SG/DGF/DFCOM du 31 janvier 2013 fixant les procédures d'attribution et de gestion des forêts communautairesMoumbogou, Carl; Boldrini, Sylvie; Morin, Amélie et alE-print/Working paper (2014)Detailed reference viewed: 18 (3 ULg) French Texts in Medieval CambridgeMorato, Nicola E-print/Working paper (2014)Detailed reference viewed: 4 (1 ULg) Bott type periodicity for the higher octonionsKreusch, Marie E-print/Working paper (2014)We study the series of complex nonassociative algebras $\bbO_n$ and real nonassociative algebras $\bbO_{p,q}$ introduced in~\cite{MGO2011}. These algebras generalize the classical algebras of octonions ... [more ▼]We study the series of complex nonassociative algebras $\bbO_n$ and real nonassociative algebras $\bbO_{p,q}$ introduced in~\cite{MGO2011}. These algebras generalize the classical algebras of octonions and Clifford algebras. The algebras $\bbO_{n}$ and $\bbO_{p,q}$ with $p+q=n$ have a natural $\Z_2^n$-grading, and they are characterized by cubic forms over the field $\Z_2$. We establish a periodicity for the algebras~$\bbO_{n}$ and $\bbO_{p,q}$ similar to that of the Clifford algebras $\mathrm{Cl}_{n}$ and~$\mathrm{Cl}_{p,q}$. [less ▲]Detailed reference viewed: 77 (35 ULg) Hubble Space Telescope Near-IR Transmission Spectroscopy of the Super-Earth HD 97658bKnutson, Heather A.; Dragomir, Diana; Kreidberg, Laura et alE-print/Working paper (2014)Recent results from the Kepler mission indicate that super-Earths (planets with masses between 1-10 times that of the Earth) are the most common kind of planet around nearby Sun-like stars. These planets ... [more ▼]Recent results from the Kepler mission indicate that super-Earths (planets with masses between 1-10 times that of the Earth) are the most common kind of planet around nearby Sun-like stars. These planets have no direct solar system analogue, and are currently one of the least well-understood classes of extrasolar planets. Many super-Earths have average densities that are consistent with a broad range of bulk compositions, including both water-dominated worlds and rocky planets covered by a thick hydrogen and helium atmosphere. Measurements of the transmission spectra of these planets offer the opportunity to resolve this degeneracy by directly constraining the scale heights and corresponding mean molecular weights of their atmospheres. We present Hubble Space Telescope near-infrared spectroscopy of two transits of the newly discovered transiting super-Earth HD 97658b. We use the Wide Field Camera 3's scanning mode to measure the wavelength-dependent transit depth in thirty individual bandpasses. Our averaged differential transmission spectrum has a median 1 sigma uncertainty of 19 ppm in individual bins, making this the most precise observation of an exoplanetary transmission spectrum obtained with WFC3 to date. Our data are inconsistent with a cloud-free solar metallicity atmosphere at the 17 sigma level. They are a good match for flat models corresponding to either a metal-rich atmosphere or a solar metallicity atmosphere with a cloud or haze layer located at pressures of a mbar or higher. [less ▲]Detailed reference viewed: 5 (0 ULg) Lettre d'information trimestrielle n° 13 du projet DACEFI 2Meunier, Quentin; Moumbogou, Carl; Boldrini, Sylvie et alE-print/Working paper (2014)Detailed reference viewed: 21 (7 ULg) WASP-20b and WASP-28b: a hot Saturn and a hot Jupiter in near-aligned orbits around solar-type starsAnderson, D. R.; Collier Cameron, A.; Hellier, C. et alE-print/Working paper (2014)We report the discovery of the planets WASP-20b and WASP-28b along with measurements of their sky-projected orbital obliquities. WASP-20b is an inflated, Saturn-mass planet (0.31 $M_{\rm Jup}$; 1.46 $R ... [more ▼]We report the discovery of the planets WASP-20b and WASP-28b along with measurements of their sky-projected orbital obliquities. WASP-20b is an inflated, Saturn-mass planet (0.31$M_{\rm Jup}$; 1.46$R_{\rm Jup}) in a 4.9-day, near-aligned (\lambda = 8.1 \pm 3.6^\circ$) orbit around CD-24 102 ($V$=10.7; F9). WASP-28b is an inflated, Jupiter-mass planet (0.91$M_{\rm Jup}$; 1.21$R_{\rm Jup}) in a 3.4-day, near-aligned (\lambda = 8 \pm 18^\circ$) orbit around a$V$=12, F8 star. As intermediate-mass planets in short orbits around aged, cool stars ($7^{+2}_{-1}$Gyr for WASP-20 and$5^{+3}_{-2}$Gyr for WASP-28; both with$T_{\rm eff}\$ < 6250 K), their orbital alignment is consistent with the hypothesis that close-in giant planets are scattered into eccentric orbits with random alignments, which are then circularised and aligned with their stars' spins via tidal dissipation. [less ▲]Detailed reference viewed: 18 (0 ULg) En el laboratorio de la ciencia ficción hispánica: una entrevistaCeballos Viro, Alvaro E-print/Working paper (2014)Detailed reference viewed: 20 (3 ULg) Lettre d'Information N° 12 projet DacefiMeunier, Quentin; Mezui Mba, C.; Boldrini, Sylvie et alE-print/Working paper (2014)Detailed reference viewed: 22 (1 ULg) Experimental Study and Statistical Modeling of an Injection Scroll Compressor Operating with R407c.Quoilin, Sylvain E-print/Working paper (2014)This working paper describes an experimental study carried out on a refrigeration scroll compressor with and without vapour injection. The test rig designed for that purposed allows evaluating the ... [more ▼]This working paper describes an experimental study carried out on a refrigeration scroll compressor with and without vapour injection. The test rig designed for that purposed allows evaluating the performance over a wide range of operating conditions, by varying the supply pressure, the injection pressure, the exhaust pressure, the supply superheating and the injection superheating. 97 Steady-state points are measured, with a maximum isentropic efficiency of 64.1% and a maximum consumed electrical power of 13.1 kW. A critical analysis of the experimental results is then carried out to evaluate the quality of the data using a machine learning method. This method based on Gaussian Processes regression, is used to build a statistical operating map of the compressor as a function of the different inputs. This statistical operating map can then be compared to the experimental data points to evaluate their accuracy. [less ▲]Detailed reference viewed: 108 (13 ULg) Zola in Sciascia. Una nota su CandidoCurreri, Luciano E-print/Working paper (2014)Detailed reference viewed: 91 (3 ULg) Von Themara nach Belgrad und zurück: Burkhard Spinnens Roman "Nevena"Dupont, Bruno E-print/Working paper (2014)Detailed reference viewed: 13 (2 ULg) Cerebral functional connectivity periodically (de)synchronizes with anatomical constraintsLiegeois, Raphaël ; Sepulchre, Rodolphe ; LAUREYS, Steven E-print/Working paper (2014)This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber ... [more ▼]This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber tractography. Instead of a static analysis based on the correlation between SC and the FC averaged over the entire fMRI time series, we propose a dynamic analysis, based on the time evolution of the correlation between SC and a suitably windowed FC. Assessing the statistical significance of the time series against random phase permutations, our data show a pronounced peak of significance for time window widths around 20-30 TR (40-60 sec). Using the appropriate window width, we show that FC patterns oscillate between phases of high modularity, primarily shaped by anatomy, and phases of low modularity, primarily shaped by inter-network connectivity. Building upon recent results in dynamic FC, this emphasizes the potential role of SC as a transitory architecture between different highly connected resting state FC patterns. Finally, we show that networks implied in consciousness-related processes, such as the default mode network (DMN), contribute more to these brain-level fluctuations compared to other networks, such as the motor or somatosensory networks. This suggests that the fluctuations between FC and SC are capturing mind-wandering effects. [less ▲]Detailed reference viewed: 14 (4 ULg) Nonparametric regression with cross-sectional data: an alternative to conditional product-limit estimatorsHeuchenne, Cédric ; Laurent, Géraldine E-print/Working paper (2014)Suppose the random vector (X,Y) satisfies the nonparametric regression model Y=m(X)+varepsilon, where m(x)=E[Y|X=x] and sigma²(x)=Var[varepsilon|X=x] are unknown smooth functions and the error varepsilon ... [more ▼]Suppose the random vector (X,Y) satisfies the nonparametric regression model Y=m(X)+varepsilon, where m(x)=E[Y|X=x] and sigma²(x)=Var[varepsilon|X=x] are unknown smooth functions and the error varepsilon has zero mean and finite variance conditionally on X=x. The pair (X,Y) is obtained by cross-sectional sampling involving left-truncated and right-censored responses. The considered model is completely nonparametric but the conditional truncation distribution is assumed to be known. The novelty of this work is twofold: first, it extends the results on cross-sectional data to the conditional case and second, it generalizes the length bias results in the conditional case to right censoring and to any truncation distribution. New estimators for m(.) and sigma²(.) are constructed and relevant tools are used to quickly provide the main asymptotic properties for this kind of estimators. Extensive simulations are carried out and show that the new estimators outperform classical nonparametric estimators for left-truncated and right-censored data (when the truncation model is known). Finally, a data set on the mortality of diabetics is analyzed. [less ▲]Detailed reference viewed: 25 (2 ULg) Inflated discrete Beta regression models for Likert and discrete rating scale outcomesTaverne, Cédric; Lambert, Philippe E-print/Working paper (2014)Discrete ordinal responses such as Likert scales are regularly proposed in questionnaires and used as dependent variable in modeling. The response distribution for such scales is always discrete, with ... [more ▼]Discrete ordinal responses such as Likert scales are regularly proposed in questionnaires and used as dependent variable in modeling. The response distribution for such scales is always discrete, with bounded support and often skewed. In addition, one particular level of the scale is frequently inflated as it cumulates respondents who invari- ably choose that particular level (typically the middle or one extreme of the scale) without hesitation with those who chose that alternative but might have selected a neighboring one. The inflated discrete beta regression (IDBR) model addresses those four critical characteristics that have never been taken into account simultaneously by existing models. The mean and the dispersion of rates are jointly regressed on covariates using an underlying beta distribution. The probability that choosers of the inflated level invariably make that choice is also regressed on covariates. Simulation studies used to evaluate the statistical properties of the IDBR model suggest that it produces more precise predictions than competing models. The ability to jointly model the location and dispersion of (the distribution of) an ordinal response, as well as to characterize the profile of subject selecting an ”inflated” alternative are the most relevant features of the IDBR model. It is illustrated with the analysis of the political positioning on a ”left-right” scale of the Belgian respondents in the 2012 European Social Survey. [less ▲]Detailed reference viewed: 16 (4 ULg) Intentionality as DispositionBoccaccini, Federico E-print/Working paper (2014)Detailed reference viewed: 14 (2 ULg) Les portfolio : vers une évaluation plus intégrée et plus cohérente avec la notion complexe de compétencePoumay, Marianne ; Maillart, Christelle E-print/Working paper (2014)Ce chapitre prend résolument le parti du témoignage et construit sur l’expérience des auteures. Il choisit quelques référents théoriques, qu’il illustre ensuite par deux expériences ciblées, l’une chez ... [more ▼]Ce chapitre prend résolument le parti du témoignage et construit sur l’expérience des auteures. Il choisit quelques référents théoriques, qu’il illustre ensuite par deux expériences ciblées, l’une chez les étudiants en logopédie/orthophonie et l’autre chez les étudiants en pédagogie de l’enseignement supérieur, deux programmes de l’Université de Liège. Il conclut sur quelques réflexions et perspectives. [less ▲]Detailed reference viewed: 48 (12 ULg) Rééquilibrer la fiscalité sur les revenus du travail et celle sur les revenus du capital : une question de justice fiscale?Bourgeois, Marc E-print/Working paper (2014)Detailed reference viewed: 40 (5 ULg) Estimation of the error distribution in nonparametric regression with cross-sectional dataHeuchenne, Cédric ; Laurent, Géraldine E-print/Working paper (2014)In this article, we study the nonparametric regression model Y=m(X)+varepsilon where m(x)=E[Y|X=x] and sigma²(x)=Var[varepsilon|X=x] are unknown smooth functions, and the error varepsilon has zero mean ... [more ▼]In this article, we study the nonparametric regression model Y=m(X)+varepsilon where m(x)=E[Y|X=x] and sigma²(x)=Var[varepsilon|X=x] are unknown smooth functions, and the error varepsilon has zero mean and finite variance conditionally on X=x. The problem consists in estimating the cumulative distribution function of the error in a nonparametric way when the couple (X,Y) is obtained by cross-sectional sampling while the positive response Y can be right-censored. We propose a new estimator for the error distribution function based on the estimators of m(.) and sigma²(.) described in Heuchenne and Laurent 2014. A bootstrap procedure is developed to solve the critical problem of the smoothing parameter choice. We assess the performance of the proposed estimator through simulations. Finally, a data set based on the mortality of diabetics is analyzed. (Heuchenne Cédric and Laurent Géraldine, Nonparametric regression with cross-sectional data: an alternative to conditional product-limit estimators, 2014) [less ▲]Detailed reference viewed: 20 (5 ULg) La psychologie morale de BrentanoBoccaccini, Federico E-print/Working paper (2014)Detailed reference viewed: 12 (0 ULg) What roles for energy cooperatives in the diffusion of distributed generation technologies?Bauwens, Thomas E-print/Working paper (2014)Whereas a centralized model of electricity infrastructure is still dominant today, many scholars advocate the diffusion of distributed generation technologies, implying geographically dispersed and small ... [more ▼]Whereas a centralized model of electricity infrastructure is still dominant today, many scholars advocate the diffusion of distributed generation technologies, implying geographically dispersed and small-scale generation units located close to consumers. However, there exist various barriers of different natures to a large-scale penetration of these technologies. In this article, we focus on the behavioral and psychological ones, emphasizing the roles that citizens have to play in this issue. More specifically, we explore a specific way of involving citizens in such diffusion, namely energy cooperatives. After presenting the driving forces of the emergence of cooperative firms in the energy sector, we examine the assets of the cooperative ownership structure from the perspectives of behavioral economics and social psychology. Our analysis enables us to build a model of how cooperatives may enhance consumer engagement in the diffusion of distributed generation technologies. This provides a basic theoretical framework for future empirical research. [less ▲]Detailed reference viewed: 124 (8 ULg) Integrating the weight of history into the alignment framework: the case of distributed generation technologiesBauwens, Thomas E-print/Working paper (2014)Whereas a centralized energy supply system is still dominant today, the energy sector is currently witnessing the development of small-scale and more geographically dispersed generation units, so-called ... [more ▼]Whereas a centralized energy supply system is still dominant today, the energy sector is currently witnessing the development of small-scale and more geographically dispersed generation units, so-called distributed generation technologies. So-called "alignment framework" proposes a very useful approach to look at this evolution. Yet, we argue in this paper that this framework does not fully take into account the inertia associated with past technological and institutional choices that may hinder future changes. Relying on the concept of socio-technical lock-in, we illustrate this point with the case of the diffusion of distributed generation technologies. Based on this analysis, we propose an adaptation of the alignment framework to integrate these elements. [less ▲]Detailed reference viewed: 65 (4 ULg)