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See detailPregnancy-Associated Glycoprotein D-56 kDa [Fragment] from Dama dama placenta - Accession number C0HJD0
Bériot, Mathilde ULg; Tchimbou Njanjo, Aline Flora; Barbato, Olimpia et al

E-print/Working paper (2013)

N-terminal microsequence obtained after purification and characterization of placental proteins in Dama dama (fallow deer). Proteins were submitted to SwissProt databank.

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See detailAlpha-2-HS-glycoprotein [Fragment] from Dama dama placenta - Accession number C0HJD1
Bériot, Mathilde ULg; Tchimbou Njanjo, Aline Flora; Barbato, Olimpia et al

E-print/Working paper (2013)

N-terminal microsequence obtained after purification and characterization of placental proteins in Dama dama (fallow deer). Proteins were submitted to SwissProt databank.

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See detailSerum albumin [Fragment] from Dama dama placenta - Accession number C0HJD2
Bériot, Mathilde ULg; Tchimbou Njanjo, Aline Flora; Barbato, Olimpia et al

E-print/Working paper (2013)

N-terminal microsequence obtained after purification and characterization of placental proteins in Dama dama (fallow deer). Proteins were submitted to SwissProt databank.

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See detailHealth Status, Disability and Retirement Incentives in Belgium
Jousten, Alain ULg; Perelman, Sergio ULg; Lefebvre, Mathieu ULg

E-print/Working paper (2013)

Many Belgian retire well before the statutory retirement age. Numerous exit routes from the labor force can be identified: old‐age pensions, conventional early retirement, disability insurance, and ... [more ▼]

Many Belgian retire well before the statutory retirement age. Numerous exit routes from the labor force can be identified: old‐age pensions, conventional early retirement, disability insurance, and unemployment insurance are the most prominent ones. We analyze the retirement decision of Belgian workers adopting an option value framework, and pay special attention to the role of health status. We estimate probit models of retirement using data from SHARE. The results show that health and incentives matter in the decision to exit from the labor market. Based on these results, we simulate the effect of potential reforms on retirement. [less ▲]

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See detailQuelle justice fiscale au niveau foncier ?
Xhignesse, Guillaume ULg; Bourgeois, Marc ULg

E-print/Working paper (2013)

Cette contribution a pour objectif de stimuler la discussion relative à la réforme du régime de la fiscalité immobilière en Belgique. Les auteurs y exposent le contexte juridique dans lequel s'inscrit une ... [more ▼]

Cette contribution a pour objectif de stimuler la discussion relative à la réforme du régime de la fiscalité immobilière en Belgique. Les auteurs y exposent le contexte juridique dans lequel s'inscrit une telle réforme, ainsi que les enjeux principaux à prendre en considération. Une série de propositions sont également énoncées. [less ▲]

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See detailUnraveling electron acceleration mechanisms in Ganymede's space environment through N-S conjugate imagery of Jupiter's aurora
Grodent, Denis ULg; Bonfond, Bertrand ULg; Gérard, Jean-Claude ULg et al

E-print/Working paper (2013)

There is strong scientific interest in Ganymede (Jupiter's third Galilean moon) and its surrounding environment, which stems from the likely presence of a liquid water ocean underneath its icy crust and ... [more ▼]

There is strong scientific interest in Ganymede (Jupiter's third Galilean moon) and its surrounding environment, which stems from the likely presence of a liquid water ocean underneath its icy crust and from its internally driven magnetic field. The interaction of the latter with Jupiter's magnetospheric plasma and its magnetic field gives rise to a unique situation in our solar system implying a mini-magnetosphere embedded within a giant-magnetosphere. This interaction generates Ganymede's ultraviolet auroral footprint in Jupiter's atmosphere. We propose to investigate the strong auroral connection between Jupiter and Ganymede and the variable characteristics of Ganymede's magnetosphere with an innovative approach, taking advantage of the large scale north-south asymmetries of Jupiter's magnetic field. The results obtained for Ganymede will be compared with the case of small injected hot plasma bubbles observed by the Galileo spacecraft and whose size and location are similar to those of Ganymede's magnetosphere. HST is currently the sole instrument capable of obtaining this information which pins down the proposed mechanisms linking the source and sink regions of auroral particles in the giant planets' magnetospheres. [less ▲]

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See detailThe state against itself
Maiorano, Diego ULg

E-print/Working paper (2013)

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See detailAnalyse des divergences entre forêts communautaires et permis de gré à gré au Gabon
Meunier, Quentin; Moumbogou; Boldrini, Sylvie et al

E-print/Working paper (2013)

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See detailNew institutional economic theories of non-profits and cooperatives: a critique from an evolutionary perspective
Bauwens, Thomas ULg

E-print/Working paper (2013)

Traditional economic theories of social enterprises rely on new institutional economics. Although these theories have an undeniable explanatory power, they display a series of non-negligible flaws ... [more ▼]

Traditional economic theories of social enterprises rely on new institutional economics. Although these theories have an undeniable explanatory power, they display a series of non-negligible flaws. Evolutionary and complexity approaches in economics may help overcome these limits. The object of this article is, in a first time, to review the different new institutional theories applied to non-profits and cooperatives and, in a second time, to present some criticisms addressed to new institutional economics. We concentrate on two controversial aspects of the latter: on the one hand, its underlying hypotheses about individuals and, in particular, bounded rationality and opportunism; on the other hand, its neglect of the emergent and evolving nature of economic phenomena and of the importance of history and the environment in agents’ institutional choices. For each criticism, we make proposals, mainly inspired by evolutionary and complexity approaches in economics, in order to overcome these limits. [less ▲]

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See detailLepton Flavor Violation in the Scotogenic Model
Toma, Takashi; Vicente, Avelino ULg

E-print/Working paper (2013)

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See detailOn the decoupling of heavy sneutrinos in low-scale seesaw models
Krauss, Manuel E.; Porod, Werner; Staub, Florian et al

E-print/Working paper (2013)

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See detailSterile neutrinos in leptonic and semileptonic decays
Abada, A.; Teixeira, A. M.; Vicente, Avelino ULg et al

E-print/Working paper (2013)

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See detailVector-like leptons: Higgs decays and collider phenomenology
Falkowski, A.; Straub, D. M.; Vicente, Avelino ULg

E-print/Working paper (2013)

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See detailExcess Return Forecast Using a Dynamic Asset Class Factor Model
Hübner, Georges ULg; Sougné, Danielle ULg; Wijnandts, Jean-Charles ULg

E-print/Working paper (2012)

We propose a Dynamic Hierarchical Factor Model using Asset classes to predict mutual funds excess returns. We use different forecast combination schemes of bivariate model considering each asset class ... [more ▼]

We propose a Dynamic Hierarchical Factor Model using Asset classes to predict mutual funds excess returns. We use different forecast combination schemes of bivariate model considering each asset class factor in isolation. Primary analysis highlights the importance to account for asset class specific variations together with between classes or common variations. Further refinements of the a priori repartition are however in order. Forecasting performance of the model outperforms the historical mean benchmark both in terms of MSPE and utility based criteria. A forecasting exercise matching more closely real-time conditions must be undertaken to validate these initial results. [less ▲]

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See detailSome misunderstood or unknown LaTeX tricks (VI)
Merciadri, Luca ULg

E-print/Working paper (2012)

Customizing a document class is important in the LaTeX world. We will consider two examples of this using the lettre document class. Next, we will consider a small fraction of a bigger LaTeX problem: the ... [more ▼]

Customizing a document class is important in the LaTeX world. We will consider two examples of this using the lettre document class. Next, we will consider a small fraction of a bigger LaTeX problem: the details of character encoding. [less ▲]

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See detailLes investisseurs institutionnels dans les Maisons de luxe familiales belges: entre diabolisation et sacralisation
Riguelle, France ULg; Van Caillie, Didier ULg

E-print/Working paper (2012)

Abstract : Belgian family luxury Houses are increasingly confrontated to a problem of independence caused by the growing influence of great financial groups and of private investment funds, on the one ... [more ▼]

Abstract : Belgian family luxury Houses are increasingly confrontated to a problem of independence caused by the growing influence of great financial groups and of private investment funds, on the one hand, and by a problem of image due to their Belgian origin, on the other hand. Nevertheless, their growing need for internationalization in order to counter the threats of the market and to seize opportunities leads them to concede one part of their control to institutional investors. The interest of this research is to study the potential impact, as perceived by the leaders of Belgian luxury Houses, of the venue of public institutional investors in their capital structure. We show that this perceived impact oscillates between sacralization and diabolisation of public institutional investors. [less ▲]

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See detailLettre d'Information trimestrielle du projet N°8
Meunier, Quentin; Moumbogou; Vermeulen, Cédric ULg

E-print/Working paper (2012)

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See detailComparison Between Mornigstar Ratings And Traditional Performance Measures Ratings
Bodson, Laurent ULg; Delhalle, Stéphanie ULg; Sougné, Danielle ULg

E-print/Working paper (2012)

In this paper, we compare Morningstar ratings with those obtained using the same methodology of rating attribution with a set of commonly used performance measures. We look at three types of investment ... [more ▼]

In this paper, we compare Morningstar ratings with those obtained using the same methodology of rating attribution with a set of commonly used performance measures. We look at three types of investment horizons: 3-year, 5-year and 10-year ratings. Our analysis focuses on Open-End US Mutual Funds available in Morningstar Direct Database from which we create three sets of 16,617, 13,505 and 7,992 funds corresponding respectively to the three investment horizons analyzed. Our results show that Morningstar ratings are very close (correlation around 80%) to ratings obtained with Sharpe’s alpha, Jensen’s alpha, Four-factor alpha and Excess returns. And less significantly, we also observe that ratings given by the Sortino ratio, Sharpe MVaR, M-squared, Sharpe ratio, One-factor information ratio, Four-factor information ratio, Prospect ratio and Stutzer index are quite similar to Morningstar’s ratings (correlation lying between 70% and 78%). At the other end of the spectrum, however, ratings obtained with Annual return diverge widely from Morningstar ratings. We also analyse which explanatory variables can explain the differences between ratings computed with Morningstar as compared with the alternative performance measures using a probit regression. We find that Load adjustments, tax and risk included by Morningstar in the computation of MRAR are often determining. Expense ratio, Return Skewness and the three factors of the Fama-French model (Beta, Size load and Book-to-market loading) can be significant determinants depending on the performance measure analyzed and on the selected investment horizon. Fund characteristics such as Age, Fund size, Turnover rate and Manager tenure are not statistically significant in determining the differences in ratings. Besides, we analyze differences between ratings (in terms of number of STARs) and we confirm previous results (i.e. the link between Morningstar’s and the alternative performance measures, but also the explanatory capacity of the load for lots of differences between ratings). Finally, we test all possible combinations of our set of performance measures, and observe that Sharpe’s alpha, excess return, Sharpe MVaR, Four-factor alpha and Jensen’s alpha are part of the best combinations. As a conclusion, Morningstar ratings can be replicated using simple and traditional performance measures but the replication is less accurate when tax and loads features are important. Therefore, Morningstar data management and access bring the most of its ratings’ value added. [less ▲]

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See detailDominique A trois fois
Demoulin, Laurent ULg

E-print/Working paper (2012)

Triple actualité pour Dominique A: un nouveau disque, une tournée de concerts, un livre dans lequel il réfléchit, de façon ouverte et nuancée, à la question de l'identité et des origines.

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See detailCoûts d’efficience des dépositaires centraux des titres des pays africains
Teuwa Nkeuwo, Mathieu Hugues ULg; Muller, Aline ULg

E-print/Working paper (2012)

This paper examines the potential of economies of scale and scope among the African central securities depository institutions. We address whether the consolidation of settlement and custody activities of ... [more ▼]

This paper examines the potential of economies of scale and scope among the African central securities depository institutions. We address whether the consolidation of settlement and custody activities of securities make these institutions efficient in light of the costs of service parameter. To do this, we rely on the translog cost function [introduced by Christensen et al. (1971)] and the constant elasticity of substitution of seven central securities depositories in Africa over the period 2004-2009. The results show the existence of significant economies of scale and scope in these institutions. The extent of these economies differs upon the size of the institution and the level of automation mechanisms to combine securities settlement and custody activities. Our findings also indicate that, unlike large institutions in countries such as South Africa and Mauritius, which have heavily invested in automation mechanisms, smaller institutions have higher service costs, which implies a need for consolidation of activities to reduce these costs. [less ▲]

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See detailComoment Risk and Stock Returns
Lambert, Marie ULg; Hübner, Georges ULg

E-print/Working paper (2012)

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See detailNancy Huston, Uurgence d'écrire
Dor, Juliette ULg

E-print/Working paper (2012)

CR de "Reflets dans un œil d'homme"

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See detailLes littératures selon Nicolas Ancion
Demoulin, Laurent ULg

E-print/Working paper (2012)

Compte rendu du roman de Nicolas Ancion "La Cravate de Simenon" paru dans une collection destinée à l'apprentissage du français.

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See detailRisk Horizon and Expected Market Returns
Hübner, Georges ULg; Lejeune, Thomas ULg

E-print/Working paper (2012)

The paper proposes an equilibrium asset pricing model that accounts of the incomplete information on returns distribution and investors' preferences. Only moments up to order four of unknown unconditional ... [more ▼]

The paper proposes an equilibrium asset pricing model that accounts of the incomplete information on returns distribution and investors' preferences. Only moments up to order four of unknown unconditional distribution can be observed, and the model does not impose that portfolio diversi fication or moments preference should hold. Using Chebyshev-type of inequalities, an intuitive risk measure (risk horizon) is introduced with reference to the speed of convergence of a security's mean return to its expectations. By an arbitrage argument, this risk measure is related to the horizon of treasury securities in a system of equations that allows the calibration of the model parameters using term structure information. In particular, the expected return on the market portfolio can be endogenously estimated inside this system. The model calibration on U.S. market data provides plausible parameters estimates and interesting cyclical patterns in the time series of the expected return. The empirical relevance of these estimates is examined with tests of statistical and economic predictive ability for stock excess returns. The results provide signi ficant evidence on the added value of the estimates when compared to popular predictors found in the literature (see a.o. Lettau and Ludvigson, 2001; Rapach and Wohar, 2006; Goyal and Welch, 2008). [less ▲]

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See detailVers une typologie de la réflexivité
Demoulin, Laurent ULg

E-print/Working paper (2012)

Il sera ici question de phénomènes réflexifs qui, au sein d’un texte littéraire, produisent des écarts sensibles et rompent le processus classique de la représentation du réel. Les cas rencontrés sont ... [more ▼]

Il sera ici question de phénomènes réflexifs qui, au sein d’un texte littéraire, produisent des écarts sensibles et rompent le processus classique de la représentation du réel. Les cas rencontrés sont étonnamment divers, tant en ce qui concerne leur structure que les effets produits. C’est pourquoi l’on se propose de les classer en six catégories distinctes : réflexivité autotélique, réflexivité poétique, réflexivité linguistique, réflexivité de l’énonciateur, réflexivité conative et réflexivité référentielle. [less ▲]

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See detailNEW CHALLENGES FOR 21ST CENTURY COMPETITION AUTHORITIES
Petit, Nicolas ULg

E-print/Working paper (2012)

This paper discusses challenges for competition authorities in the 21st century. Those challenges were identified on the basis of a statistical review of the articles published since January 2011 in five ... [more ▼]

This paper discusses challenges for competition authorities in the 21st century. Those challenges were identified on the basis of a statistical review of the articles published since January 2011 in five major antitrust law journals. The assumption underlying this literature review is that the topics that statistically attract the most the attention from contemporary antitrust scholars are those that will likely constitute the main challenges for 21st century competition authorities. [less ▲]

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See detailPlan Simple de Gestion à vocation de production de bois énergie
Dubiez, Emilien; Vermeulen, Cédric ULg; Larzilière, Adélaïde

E-print/Working paper (2012)

Les zones d’interventions du Projet Makala présentent des contextes différents liés à l’occupation spatiale coutumière, l’organisation des structures sociales traditionnelles (lignage, clan, chefferie ... [more ▼]

Les zones d’interventions du Projet Makala présentent des contextes différents liés à l’occupation spatiale coutumière, l’organisation des structures sociales traditionnelles (lignage, clan, chefferie coutumière), les types de formations végétales présentes dans la zone et les activités principales des populations. L’ensemble de ces éléments structure l’intervention du projet dans son objectif d’aménagement des espaces forestiers périurbains dégradés. Des enquêtes d’identification du finage et des terroirs villageois partenaires ont d’abord été réalisées pour caractériser le contexte social et environnemental d’intervention. Les données recueillies ont constituées la base de travail de la construction du processus d’élaboration des Plans Simples de Gestion (PSG). Le présent document présente les étapes structurant le PSG, l’outil de démarche participatif permettant une appropriation collective du processus et les activités techniques développées pour la reconstitution des espaces forestiers dégradés. [less ▲]

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See detailOrganizational and Institutional Arrangements for e-Government : A Preliminary Report on Contemporary IT Management Approaches in US State Governments
Markus, M. Lynne; Jacobson, Dax D.; Bui, Quang Neo et al

E-print/Working paper (2012)

The success of e-government is believed to depend in part on the organizational and institutional arrangements that governments enact for the management of their IT resources. This paper develops the ... [more ▼]

The success of e-government is believed to depend in part on the organizational and institutional arrangements that governments enact for the management of their IT resources. This paper develops the conceptualization of IT management arrangements by considering possible interactions between two dimensions — 1) the organization of IT activities and 2) control over decisions about IT activities (also known as governance) — for each of two categories of IT activities — 1) IT projects (such as website development) and 2) IT services (such as the operation of networks). In addition, the paper provides preliminary empirical evidence obtained from applying this expanded conceptualization in the context of American state governments. Many states appear to employ centralization of IT activities to offset decentralization of IT control and vice versa. Consequently, neither dimension alone provides a good characterization of governmental IT management arrangements. These findings have the potential to enhance our understanding of the barriers to, and enablers of, e-government success. [less ▲]

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See detailLettre d'information trimestrielle N°7 Projet Dacefi
Meunier, Quentin; Boldrini, Sylvie ULg; Boukouendji, B. et al

E-print/Working paper (2012)

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See detailConditional asset allocation: Does Market-Wide Liquidity Matter?
Bazgour, Tarik ULg; Sougné, Danielle ULg; Heuchenne, Cédric ULg

E-print/Working paper (2012)

This paper investigates the effect of market-wide liquidity on optimal portfolio allocations across US equity portfolios sorted by size and book-to-market characteristics. In particular, we consider a ... [more ▼]

This paper investigates the effect of market-wide liquidity on optimal portfolio allocations across US equity portfolios sorted by size and book-to-market characteristics. In particular, we consider a single-period investor with a relative risk aversion of 5, and use the nonparametric approach of Brandt (1999) to directly express optimal portfolio weights as functions of market-wide liquidity innovations. We find, first, that the effect of market-wide liquidity is a decreasing function of investment horizon. Second, this effect is stronger in allocations in the small stock portfolio and gets weaker as we move towards the large stock portfolio. Third, conditional allocations in risky asset(s) decrease and exhibit shifts towards more liquid and less risky assets as market-wide liquidity worsens. Overall, our results show that allocations based on market-wide liquidity as a signal capture many phenomena that have been identified by researchers in the US market, such as the so-called “flight-to-safety”, flight-to-quality” and “flight-to-liquidity” episodes. Furthermore, in an out-of-sample test, results demonstrate the superior performance of a strategy based on market-wide liquidity compared to a benchmark strategy. [less ▲]

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See detailHigher-Moment Risk Exposures in Hedge Funds
Lambert, Marie ULg; Hübner, Georges ULg; Papageorgiou, Nicolas

E-print/Working paper (2012)

The paper singles out the key roles of US equity skewness and kurtosis in the determination of the market premia embedded in Hedge Fund returns. We propose a conditional higher-moment asset pricing model ... [more ▼]

The paper singles out the key roles of US equity skewness and kurtosis in the determination of the market premia embedded in Hedge Fund returns. We propose a conditional higher-moment asset pricing model with location, trading and higher-moment factors in order to describe the dynamics of the Equity Hedge (Market Neutral, Short Selling and Long/Short strategies), Event Driven, Relative Value, and Funds of Hedge Funds styles. The volatility, skewness and kurtosis implied in the US options markets are used by Hedge Fund managers as instruments to anticipate market movements. Managers should adjust their market exposure in response to variations in the implied higher moments. We show that higher-moment premia improve a conditional asset pricing model both in terms of explanatory power (R-squares and Schwarz criterion) and specification errors across all Hedge Fund styles. [less ▲]

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See detailThe design of performance monitoring systems in healthcare organizations : a stakeholder perspective
Rouhana, Rima; Van Caillie, Didier ULg

E-print/Working paper (2012)

Monitoring the hospital’s performance is evolving over time in search of more efficiency by integrating additional levels of care, reducing costs and keeping stuff up-to-date. To fulfill these three ... [more ▼]

Monitoring the hospital’s performance is evolving over time in search of more efficiency by integrating additional levels of care, reducing costs and keeping stuff up-to-date. To fulfill these three potentially divergent aspects and to monitor performance, healthcare administrators are using dissimilar management control tools. To explain why, we suggest to go beyond traditional contingent factors to assess the role of the different stakeholders (governments, patients, authorities, personnel and administrators) that are at the heart of any healthcare organization. So, the main interest of our empirical study is to appraise how healthcare managers can foster strategic “alignment” in chaotic environments. To investigate this subject, we rely first on seminal studies to appraise the role of the main healthcare players and their influence on some organizational attributes (essentially size, lifecycle, structure, climate and technology in use). We then consider the managerial awareness and the perception of a suitable management control system (MCS) to promote a strategy-focused organization. Our methodology is based on a qualitative approach of twenty-two case studies, lead in two heterogeneous environments (Belgium and Lebanon). This method allows to illustrate, for each healthcare player, its positioning within the healthcare systems. Thus, we define how its role, its perception and its responsiveness manipulate the organization’s internal climate and shape the design of the performance monitoring systems. Our findings are expected to add knowledge on the reasons of the choice of adequate management systems, within three different healthcare organizational structures: university, general/university and general hospitals. [less ▲]

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See detailLes chemins de l’… sont pavés de bonnes intentions
Choffray, Jean-Marie ULg

E-print/Working paper (2012)

C’est un fait connu : « Les Liégeois ont été plus que tous les ans domptés. Néanmoins, ils ont toujours relevé leurs crestes » Citation de Michel de L’Hospital, 1558, gravée au fronton du bâtiment de la ... [more ▼]

C’est un fait connu : « Les Liégeois ont été plus que tous les ans domptés. Néanmoins, ils ont toujours relevé leurs crestes » Citation de Michel de L’Hospital, 1558, gravée au fronton du bâtiment de la Cité Administrative de Liège. [less ▲]

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See detailSummer 2012 & The Blues - Chicago Blues Festival , Juin 2012
Sacré, Robert ULg

E-print/Working paper (2012)

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See detailSocial Security, Ageing and Economic Integration
Artige, Lionel ULg; Dedry, Antoine; Pestieau, Pierre ULg

E-print/Working paper (2012)

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See detailThe EMES Approach of Social Enterprise in a Comparative Perspective
Defourny, Jacques ULg; Nyssens, Marthe

E-print/Working paper (2012)

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See detailSummer 2012 & The blues 2012 pt 2 - Aurora's Blues on the Fox, June 2012
Sacré, Robert ULg

E-print/Working paper (2012)

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See detailNotes éparses d'un lecteur enthousiaste
Demoulin, Laurent ULg

E-print/Working paper (2012)

Compte rendu de "Carnet de Corée", ouvrage de Serge Delaive, mêlant littérature et photographies au sujet de trois voyages effectués en Corée sur les traces de la mère de sa compagne.

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See detailDe nieuwe fiscale antimisbruikregel en de gevolgen voor vermogensplanning
Bourgeois, Marc ULg; Nollet, Aymeric ULg

E-print/Working paper (2012)

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See detailA New Shift-Share Method
Artige, Lionel ULg; Van Neuss, Leif ULg

E-print/Working paper (2012)

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See detailWanted ! Avez-vous vu ces plantes ? La conservation des plantes messicoles dans le cadre du Programme Agroenvironnemental wallon
Piqueray, Julien ULg; Gilliaux, Valentin ULg; Mahy, Grégory ULg

E-print/Working paper (2012)

Afin de mener à bien un projet de conservation des plantes messicoles menacées, la Faculté AgroBioTech de Gembloux appelle à diffuser vos observations de terrain au DEMNA

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See detailGenerational Accounting in Belgium: Fiscal Sustainability at a Glance
Decoster, André; Flawinne, Xavier ULg; Vanleenhove, Pieter

E-print/Working paper (2012)

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See detailLes Wallons du Wisconsin
Lempereur, Françoise ULg

E-print/Working paper (2012)

In the middle of the XIXe century, thousands of Walloon left Belgium to settle in Wisconsin, more than 3100 miles away.

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See detailDo Mutual Fund Investors Still Trust Standard Risk-Adjusted Performance Measures?
Bodson, Laurent ULg; Cave, Arnaud; Sougné, Danielle ULg

E-print/Working paper (2012)

We study the relationship between the risk-adjusted performance of mutual funds and their money flows (i.e. their subscriptions and redemptions). Testing the most traditional risk-adjusted performance ... [more ▼]

We study the relationship between the risk-adjusted performance of mutual funds and their money flows (i.e. their subscriptions and redemptions). Testing the most traditional risk-adjusted performance measures, we identify the ones which best explain the flows of equity, bond or mixed funds. The risk-adjusted performance measures which attract the most the attention from investors are the Information ratios (mono- and multi-factor), the M-squared and the Sharpe ratios (traditional Sharpe ratios and Sharpe MVaR). We may conclude that fund managers who want to maximize their AuM (and, if applicable, increase their AuM based fees) must mainly focus their efforts on improving these standard performance measures. Furthermore, we also demonstrate that the performance-flow relationship is concave then convex. Indeed, amongst the funds with a negative performance, those achieving the worst results are affected by disproportionately high net outflows whereas, on the opposite side of the spectrum, the most successful funds experience much higher capital inflows. [less ▲]

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See detailNewsletter n°6 - DACEFI
Meunier, Quentin; Moumbogou, Carl; Morin, Amélie et al

E-print/Working paper (2012)

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See detailEcaussinnes 2012 - Spring Blues Festival
Sacré, Robert ULg

E-print/Working paper (2012)

Compte-rendu du Spring Blues Festival d'Ecaussinnes, le 19 mai 2012

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See detailRenforcer la formation en sciences humaines en réduisant l’histoire-géo : cherchez l’erreur!
Jadoulle, Jean-Louis ULg

E-print/Working paper (2012)

Cette "carte blanche" fait suite à la décision de la Ministre de l'Enseignement obligatoire, Marie-Dominique Simonet, de réviser les grilles - horaires de l'enseignement qualifiant. Elle reprend la teneur ... [more ▼]

Cette "carte blanche" fait suite à la décision de la Ministre de l'Enseignement obligatoire, Marie-Dominique Simonet, de réviser les grilles - horaires de l'enseignement qualifiant. Elle reprend la teneur d'une lettre qui lui a été adressée et qui a été co-signée par plus de 140 enseignants, formateurs d'enseignants et membres de la société civile. [less ▲]

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See detailDo Mutual Fund Investors Still Trust Standard Risk-Adjusted Performance Measures?
Sougné, Danielle ULg; Bodson, Laurent ULg; Cave, Arnaud

E-print/Working paper (2012)

We study the relationship between the past performance of mutual funds and their capital flows (i.e. their subscriptions and redemptions). Testing the most traditional risk-adjusted performance measures ... [more ▼]

We study the relationship between the past performance of mutual funds and their capital flows (i.e. their subscriptions and redemptions). Testing the most traditional risk-adjusted performance measures, we identify the ones which best explain the flows of US equity mutual funds. [less ▲]

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See detailA Global Approach to Mutual Funds Market Timing Ability
Sougné, Danielle ULg; Bodson, Laurent ULg; Cavenaile, Laurent

E-print/Working paper (2012)

In this paper, we globally investigate market timing abilities of mutual fund managers from the three perspectives: market return, market-wide volatility and aggregate liquidity. We propose a new ... [more ▼]

In this paper, we globally investigate market timing abilities of mutual fund managers from the three perspectives: market return, market-wide volatility and aggregate liquidity. We propose a new specification to study market timing. Instead of considering an average market exposure for mutual funds, we allow mutual fund market betas to follow a random walk in the absence of market timing ability. As a consequence, we capture market exposure dynamics which is really due to manager market timing skills while allowing dynamics to come from other sources than market timing. We find that on average 6% of mutual funds display return market timing abilities while this percentage amounts to respectively 13% and 14% for volatility and liquidity market timing. We also analyze market timing by investment strategies and for surviving and dead funds. Dead fund exhibit lower volatility and liquidity timing skills than live funds. [less ▲]

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See detailTraffic Situation Assessment and Intervention Strategy of a Collision Avoidance System based on Galileo Satellite Positioning
Christen, Fréderic ULg; Ewald, Christian; Eckstein, Lutz et al

E-print/Working paper (2012)

Nowadays, collision avoidance systems (CAS) are an intensive research topic since the majority of all traffic accidents are collisions that are caused due to inattention or unadjusted driving behavior of ... [more ▼]

Nowadays, collision avoidance systems (CAS) are an intensive research topic since the majority of all traffic accidents are collisions that are caused due to inattention or unadjusted driving behavior of the driver. Up to date prototypic CAS are based on on-board environmental sensors, such as camera or radar systems, that scan the vehicle's surrounding environment in order to assess the situation's hazardousness. The functionality of the used sensors under varying environmental conditions and the limited sensor covering area require an enormous effort to ensure a reliable detection of obstacles, and thus limit the application of the systems. In order to expand the operating field of such systems, a Galileo-based CAS will be developed within the project ‘Galileo above’ (application centre for ground based traffic). This advanced driver assistance system (ADAS) detects surrounding vehicles that are on collision course and reacts autonomously, if the driver does not intervene to avoid the crash. For this purpose the system initiates an emergency stop and/or an emergency steering maneuver. For the development of the CAS the Galileo test centre automotiveGATE in Aldenhoven, Germany will be used. On this test area pseudolites will be installed which provide Galileo-like navigation signals. Thus, the development respectively tuning of Galileo-based vehicle systems will be enabled, so as to have them available on the market when the Galileo satellite system reaches its full operational capability (FOC). The focus of this paper is on the traffic situation assessment and intervention strategy of the CAS. This includes the perception and analysis of the driving situation, the detection of potential collision situation, the definition of an adequate system reaction and the planning of an evasion trajectory. Furthermore, an outlook on the model predictive control for longitudinal and/or lateral control (braking and/or steering maneuver) will be presented. [less ▲]

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See detailInstitutional Change and Legislative Stability: Explicit and Contested Decision-Making in the EU Council (1995-2010)
Van Aken, Wim ULg

E-print/Working paper (2012)

In contrast to general expectations the growth of EU membership as well as European treaty reform has not had any significant impact on the Council’s overall legislative and roll call activity. On the ... [more ▼]

In contrast to general expectations the growth of EU membership as well as European treaty reform has not had any significant impact on the Council’s overall legislative and roll call activity. On the basis of a new dataset representing the total population of public roll calls and recorded votes in the Council this paper explains why the EU Council has been so successful in guaranteeing legislative and roll call stability between 1995 and 2010. The quantitative and qualitative analysis finds that frontloading legislation, changing voting behaviour, reinforcement of existing coalition patterns and the successful adjustment of newer Member States to the EU Council have contributed to the EU Council’s decision-making capacity during the observed 16 years. In explaining the apparent contradiction between institutional change and the Council’s legislative stability this paper contributes to our knowledge of the functioning, the decision-making processes and the geography of contestation in the EU Council. [less ▲]

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See detailExtensions of superalgebras of Krichever-Novikov type
Kreusch, Marie ULg

E-print/Working paper (2012)

An explicit construction of central extensions of Lie superalgebras of Krichever-Novikov type is given. In the case of Jordan superalgebras related to the superalgebras of Krichever-Novikov type we ... [more ▼]

An explicit construction of central extensions of Lie superalgebras of Krichever-Novikov type is given. In the case of Jordan superalgebras related to the superalgebras of Krichever-Novikov type we calculate a 1-cocycle with coefficients in the dual space. [less ▲]

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See detailThe size and book-to-market effects revisited
Lambert, Marie ULg; Hübner, Georges ULg

E-print/Working paper (2012)

Detailed reference viewed: 17 (2 ULg)
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See detailBriefe an Casanova
Roggendorf, Cécile de; Viehöver, Vera ULg

E-print/Working paper (2012)

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See detailSOUTHERN BLUES NIGHT Heerlen, Hollande) 2012
Sacré, Robert ULg

E-print/Working paper (2012)

Detailed reference viewed: 8 (0 ULg)
See detailRossano Rosi: triangle amoureux et paternité
Demoulin, Laurent ULg

E-print/Working paper (2012)

Compte rendu du roman de Rossano Rosi Stabat Pater paru aux Impressions nouvelles en mars 2012.

Detailed reference viewed: 16 (2 ULg)
See detailDans le discontinu de la vie
Demoulin, Laurent ULg

E-print/Working paper (2012)

Compte rendu du roman de Caroline Lamarche La Chienne de Naha paru chez Gallimard en janvier 2012.

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See detailNewsletter n° 5 - DACEFI 2
Meunier, Quentin; Moumbogou, Carl; Angwé, A. et al

E-print/Working paper (2012)

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See detailEchecs
Demoulin, Laurent ULg

E-print/Working paper (2012)

Echecs est un roman inédit de Jean-Philippe Toussaint, antérieur à La Salle de bain. Il est ici édité avec un apparat critique: variantes et notes critiques.

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See detailOxford Centre for Evidence‐Based Medicine 2011 Levels of Evidence ‐ Traduction française
OCEBM Levels of Evidence Working Group; Durieux, Nancy ULg; Pasleau, Françoise ULg et al

E-print/Working paper (2012)

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See detailHeinrich Rickert's Philosophy of History And Its Reception 1896-1936: An Annotated Bibliography
Dewalque, Arnaud ULg

E-print/Working paper (2012)

Annotated bibliography of the main philosophical texts which testify the reception of Heinrich Rickert's much-discussed view on historical sciences from 1896 to 1936.

Detailed reference viewed: 52 (2 ULg)
See detailHow to optimally load a set of containers into an aircraft
Schyns, Michael ULg; Limbourg, Sabine ULg; Laporte, Gilbert

E-print/Working paper (2012)

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See detailLe design du système de contrôle de gestion dans les PMI tunisiennes: une modélisation contingente
Ghorbel, Jihene ULg; Van Caillie, Didier ULg

E-print/Working paper (2012)

A l'heure actuelle, il existe relativement peu de recherches qui traitent du système de contrôle de gestion des PME, spécialement dans le contexte tunisien, malgré leur importance économique. La présente ... [more ▼]

A l'heure actuelle, il existe relativement peu de recherches qui traitent du système de contrôle de gestion des PME, spécialement dans le contexte tunisien, malgré leur importance économique. La présente communication vise dès lors à élaborer un modèle théorique expliquant le design du système de contrôle de gestion dans les PMI tunisiennes, au départ d'une analyse de la littérature portant spécifiquement soit sur les PMI tunisiennes, soit sur le système de contrôle de gestion de la PME. Cette étude est réalisée en privilégiant deux angles d'analyse particulièrement importants au vu du contexte tunisien, à savoir la taille de l'entreprise et son positionnement sur le cycle de vie. [less ▲]

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See detailAccrued Pension Rights in Belgium: Microsimulation of Reforms
Jousten, Alain ULg; Perelman, Sergio ULg; Tarantchenko, Ekaterina ULg et al

E-print/Working paper (2012)

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See detailLes enjeux prospectifs wallons à la lumière d’un dispositif participatif
Guyot, Jean-Luc; Rieppi, Stéphane ULg; Van Cutsem, Michaël et al

E-print/Working paper (2012)

La prospective a souvent recours à la démarche participative. Fréquemment, dans son travail analytique, le prospectiviste fait intervenir les acteurs concernés par le système qu'il examine, que ceux-ci ... [more ▼]

La prospective a souvent recours à la démarche participative. Fréquemment, dans son travail analytique, le prospectiviste fait intervenir les acteurs concernés par le système qu'il examine, que ceux-ci opèrent dans ce système ou qu’ils possèdent une expertise particulière par rapport à celui-ci. Dans la majorité des cas, cette intervention s’effectue au cours de l’exercice prospectif. Le présent working paper expose un autre type de situation : l’intervention et la participation des acteurs se placent ici en amont du travail prospectif, au moment de la délimitation des enjeux et des thématiques à considérer dans le cadre du développement d’un programme de recherche. L'expérience présentée par les auteurs, bien qu’elle recoure à l’utilisation d’un outil relativement classique en prospective, à savoir le Delphi, revêt un aspect original. Développée auprès de deux publics distincts, des équipes de recherche d’une part et des membres de l’administration wallonne, d’autre part, elle a permis d’identifier un certain nombre d’enjeux prospectifs majeurs pour la Wallonie et de définir des objets de recherche en rapport avec ces derniers. L'identification et la présentation de ces enjeux fait l’objet du présent texte. Dans un premier temps, celui-ci se propose de décrire le processus d’identification de ces enjeux et, dans un second temps, d’expliciter la nature de ceux-ci. [less ▲]

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See detailModule 3, techniques de reconstitution forestière
Dubiez, Emilien; Vermeulen, Cédric ULg

E-print/Working paper (2012)

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See detailMeasuring Downside and Extreme Risk Allocation in Equity Hedge Funds
Lambert, Marie ULg

E-print/Working paper (2012)

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See detailInternet-Based Investing at the Edge of Chaos
Choffray, Jean-Marie ULg

E-print/Working paper (2012)

This paper presents a simple, seven-step approach, to surviving on World Street: an investment environment characterized by high frequency trading system; over leveraged shadow entities and hedge funds ... [more ▼]

This paper presents a simple, seven-step approach, to surviving on World Street: an investment environment characterized by high frequency trading system; over leveraged shadow entities and hedge funds; flash crashes, incompetent management, reverse merger frauds, dot bubble 2.0 IPOs and stealth central banks’ actions. Its goal is to help you design efficient investment strategies while protecting your assets. It is based on a personal research conducted over the last ten years, involving hundreds of observations, investment simulations and actual decisions. [less ▲]

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See detailCinéma 3D: d'une révolution à l'autre
Thonon, Jonathan ULg

E-print/Working paper (2012)

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See detailOn the use of adhesion parameters to validate models specified using systems of affine differential equations
Jaeger, Jonathan ULg; Lambert, Philippe ULg

E-print/Working paper (2012)

A strategy for the selection of system of differential equations is proposed based on Bayesian ODE-penalized B-spline approach. It estimates the ODE parameters, approximates the solution of the ODE model ... [more ▼]

A strategy for the selection of system of differential equations is proposed based on Bayesian ODE-penalized B-spline approach. It estimates the ODE parameters, approximates the solution of the ODE model and quantifies the suitability of the proposed differential equations to model the dynamics of the observed state functions. Simulation study confirms that these ODE-adhesion parameters are able to question a system of differential equations as a descriptor of the dynamics in the state functions. This methodology is illustrated on a pharmacokinetic study. [less ▲]

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See detailEntrepreneuriat social
Mertens de Wilmars, Sybille ULg; Defourny, Jacques ULg

E-print/Working paper (2012)

Detailed reference viewed: 39 (7 ULg)
Peer Reviewed
See detaild'Hane-Steenhuyse (Charles-François)
Vandersmissen, Jan ULg

E-print/Working paper (2012)

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See detailLe financement des associations en Belgique francophone
Mertens de Wilmars, Sybille ULg; Marée, Michel ULg

E-print/Working paper (2012)

En raison de la nature de leurs activités et de leur finalité non lucrative, les associations rencontrent des problèmes spécifiques de financement, que ce soit au niveau de leurs opérations courantes ou ... [more ▼]

En raison de la nature de leurs activités et de leur finalité non lucrative, les associations rencontrent des problèmes spécifiques de financement, que ce soit au niveau de leurs opérations courantes ou de leurs dépenses d'investissements. Toutefois, Il existe encore peu d'études empiriques sur cette question dans les pays francophones, de sorte que nombre d'a priori - comme par exemple le fait que les associations auraient peu de garanties à offrir aux banques - sont communément admis sans qu'ils soient validés par des données de terrain. Pour mieux cerner la problématique du financement de l'associatif dans ses dimensions concrètes, on a réalisé un premier "état des lieux" du financement du secteur associatif en Belgique francophone (Wallonie et Bruxelles) en procédant à une enquête auprès d'un échantillon représentatif. Un des enseignements de cette recherche concerne précisément les relations avec les institutions bancaires. En cas de difficultés de trésorerie, la moitié à peine des associations recourent au crédit de caisse, les autres préférant se tourner vers leurs membres, vers les pouvoirs publics ou encore vers une autre association. Moins nombreuses encore sont les associations qui s'adressent aux banques pour financer leurs investissements. Mais contrairement à l'opinion courante, la principale raison ne réside ni dans les difficultés d'obtention d'un crédit, ni dans la lourdeur des formalités nécessaires : si les associations n'empruntent guère aux banques, c'est essentiellement pour des raisons de principe (ne pas s'endetter auprès des institutions bancaires). Ces raisons sont vraisemblablement liées, d'une part, à une aversion plus marquée du risque que les PME et, d'autre part, à une prise de distance à l'égard des principes de l'économie marchande. [less ▲]

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See detailBronfenbrenner, écologie du développement humain. Réflexion et action pour la promotion de la santé
Absil, Gaëtan ULg; Vandoorne, Chantal ULg; Demarteau, Michel

E-print/Working paper (2012)

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See detailContextual Multi-armed Bandits for the Prevention of Spam in VoIP Networks
Jung, Tobias ULg; Martin, Sylvain ULg; Ernst, Damien ULg et al

E-print/Working paper (2012)

In this paper we argue that contextual multi-armed bandit algorithms could open avenues for designing self-learning security modules for computer networks and related tasks. The paper has two ... [more ▼]

In this paper we argue that contextual multi-armed bandit algorithms could open avenues for designing self-learning security modules for computer networks and related tasks. The paper has two contributions: a conceptual one and an algorithmical one. The conceptual contribution is to formulate -- as an example -- the real-world problem of preventing SPIT (Spam in VoIP networks), which is currently not satisfyingly addressed by standard techniques, as a sequential learning problem, namely as a contextual multi-armed bandit. Our second contribution is to present CMABFAS, a new algorithm for general contextual multi-armed bandit learning that specifically targets domains with finite actions. We illustrate how CMABFAS could be used to design a fully self-learning SPIT filter that does not rely on feedback from the end-user (i.e., does not require labeled data) and report first simulation results. [less ▲]

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See detailBringing Belgian public finances to a sustainable path
Jousten, Alain ULg; Hoj, Jens; Kozluk, Tomasz

E-print/Working paper (2012)

Economic growth is projected to be strengthening from mid-2011 onwards, but will be insufficient to restore the sustainability of public finances. The Belgian strategy to prefund ageing costs by ... [more ▼]

Economic growth is projected to be strengthening from mid-2011 onwards, but will be insufficient to restore the sustainability of public finances. The Belgian strategy to prefund ageing costs by generating fiscal surpluses to bring down public debt was derailed by the global crisis. Restoring the strategy is a priority, especially as spreads on Belgian debt have increased. This will require cuts in public spending, improving efficiency of policies, containing the growth of ageing-related costs and making the tax system more conducive to growth. While past experiences, such as in the 1990s, have shown that successful large consolidations are feasible, the task seems even more difficult this time as potential growth will be muted and interest rates are likely to increase. In this context, a credible fiscal consolidation plan requires the participation of all governments. Its effectiveness can be strengthened by improving the fiscal framework, in particular by introducing multi-year budgets, annual expenditure rules consistent with long-term targets and an enhanced role of an independent fiscal policy watchdog [less ▲]

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See detailA capacity game in transportation management
Amand, Guillaume ULg; Arda, Yasemin ULg

E-print/Working paper (2012)

Detailed reference viewed: 29 (14 ULg)
Peer Reviewed
See detailSolvyns (François-Balthazar)
Vandersmissen, Jan ULg

E-print/Working paper (2012)

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See detailInventaire des papiers Michel Gloesener (1794-1876)
Caulier-Mathy, Nicole; Haesenne-Peremans, Nicole; Oger, Cécile ULg

E-print/Working paper (2012)

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See detailThe Retirement of the Migrant Labor Force: Pension Portability and Beyond
Jousten, Alain ULg

E-print/Working paper (2012)

The specificities of the workforce with a migrant background are often neglected in studies of retirement. Similarly, many studies of migration’s impact on pensions often focus on aggregate outcomes – ... [more ▼]

The specificities of the workforce with a migrant background are often neglected in studies of retirement. Similarly, many studies of migration’s impact on pensions often focus on aggregate outcomes – system sustainability or distributive characteristics. The present paper provides a fresh look at the nexus between these two literatures. It discusses the impact of the European social security coordination mechanisms on individual decision‐making and on the functioning of social security systems – with a focus on retirement. The paper argues that such effects are non‐negligible and are likely to have major policy consequences. [less ▲]

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See detailLow-rank optimization with trace norm penalty
Mishra, Bamdev ULg; Meyer, Gilles ULg; Bach, Francis et al

E-print/Working paper (2012)

The paper addresses the problem of low-rank trace norm minimization. We propose an algorithm that alternates between fixed-rank optimization and rank-one updates. The fixed-rank optimization is ... [more ▼]

The paper addresses the problem of low-rank trace norm minimization. We propose an algorithm that alternates between fixed-rank optimization and rank-one updates. The fixed-rank optimization is characterized by an efficient factorization that makes the trace norm differentiable in the search space and the computation of duality gap numerically tractable. The search space is nonlinear but is equipped with a particular Riemannian structure that leads to efficient computations. We present a second-order trust-region algorithm with a guaranteed quadratic rate of convergence. Overall, the proposed optimization scheme converges super-linearly to the global solution while still maintaining complexity that is linear in the number of rows of the matrix. To compute a set of solutions efficiently for a grid of regularization parameters we propose a predictor-corrector approach on the quotient manifold that outperforms the naive warm-restart approach. The performance of the proposed algorithm is illustrated on problems of low-rank matrix completion and multivariate linear regression. [less ▲]

Detailed reference viewed: 47 (17 ULg)
See detailA Riemannian geometry for low-rank matrix completion
Mishra, Bamdev ULg; Karavadi, Adithya Apuroop; Sepulchre, Rodolphe ULg

E-print/Working paper (2012)

We propose a new Riemannian geometry for fixed-rank matrices that is specifically tailored to the low-rank matrix completion problem. Exploiting the degree of freedom of a quotient space, we tune the ... [more ▼]

We propose a new Riemannian geometry for fixed-rank matrices that is specifically tailored to the low-rank matrix completion problem. Exploiting the degree of freedom of a quotient space, we tune the metric on our search space to the particular least square cost function. At one level, it illustrates in a novel way how to exploit the versatile framework of optimization on quotient manifold. At another level, our algorithm can be considered as an improved version of LMaFit, the state-of-the-art Gauss-Seidel algorithm. We develop necessary tools needed to perform both first-order and second-order optimization. In particular, we propose gradient descent schemes (steepest descent and conjugate gradient) and trust-region algorithms. We also show that, thanks to the simplicity of the cost function, it is numerically cheap to perform an exact linesearch given a search direction, which makes our algorithms competitive with the state-of-the-art on standard low-rank matrix completion instances. [less ▲]

Detailed reference viewed: 87 (17 ULg)
See detailFixed-rank matrix factorizations and Riemannian low-rank optimization
Mishra, Bamdev ULg; Meyer, Gilles ULg; Bonnabel, Silvere et al

E-print/Working paper (2012)

Motivated by the problem of learning a linear regression model whose parameter is a large fixed-rank non-symmetric matrix, we consider the optimization of a smooth cost function defined on the set of ... [more ▼]

Motivated by the problem of learning a linear regression model whose parameter is a large fixed-rank non-symmetric matrix, we consider the optimization of a smooth cost function defined on the set of fixed-rank matrices. We adopt the geometric optimization framework of optimization on Riemannian matrix manifolds. We study the underlying geometries of several well-known fixed-rank matrix factorizations and then exploit the Riemannian geometry of the search space in the design of a class of gradient descent and trust-region algorithms. The proposed algorithms generalize our previous results on fixed-rank symmetric positive semidefinite matrices, apply to a broad range of applications, scale to high-dimensional problems and confer a geometric basis to recent contributions on the learning of fixed-rank non-symmetric matrices. We make connections with existing algorithms in the context of low-rank matrix completion and discuss relative usefulness of the proposed framework. Numerical experiments suggest that the proposed algorithms compete with the state-of-the-art and that manifold optimization offers an effective and versatile framework for the design of machine learning algorithms that learn a fixed-rank matrix. [less ▲]

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See detailAn expanding Universe without dark matter and dark energy
Magain, Pierre ULg

E-print/Working paper (2012)

Assuming that observers located inside the Universe measure a time flow which is different from the time appearing in the Friedmann-Lemaıtre equation, and determining this time flow such that the Universe ... [more ▼]

Assuming that observers located inside the Universe measure a time flow which is different from the time appearing in the Friedmann-Lemaıtre equation, and determining this time flow such that the Universe always appears flat to these observers, we derive a simple cosmological model which allows to explain the velocity dispersions of galaxies in galaxy clusters without introducing dark matter. It also solves the horizon problem without recourse to inflation. Moreover, it explains the present acceleration of the expansion without any resort to dark energy and provides a good fit to the observations of distant supernovæ. Depending on the present value of the matter-energy density, we calculate an age of the Universe between 15.4 and 16.5 billion years, ignificantly larger than the 13.7 billion years of the standard CDM model. Our model has a slower expansion rate in the early epochs, thus leaving more time for the formation of structures such as stars and galaxies. [less ▲]

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See detailStrategic bypass deterrence
Bloch, Francis; Gautier, Axel ULg

E-print/Working paper (2012)

In liberalized network industries, entrants can either compete for service using the existing infrastructure (access) or deploy their own infrastructure capacity (bypass). In this paper, we demonstrate ... [more ▼]

In liberalized network industries, entrants can either compete for service using the existing infrastructure (access) or deploy their own infrastructure capacity (bypass). In this paper, we demonstrate that, under the threat of bypass, the access price set by an unregulated and vertically integrated incumbent is compatible with productive efficiency. This means that the entrant bypasses the existing infrastructure only if it can produce the network input more efficiently. We show that the incumbent lowers the access price compared to the ex-post efficient level to strategically deter inefficient bypass by the entrant. Accordingly, from a productive efficiency point of view, there is no need to regulate access prices when the entrant has the option to bypass. Despite that, we show that restricting the possibilities of access might be profitable for consumers and welfare because competition is fiercer under bypass. [less ▲]

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See detailGermanistische Mitteilungen 38.1
Bosse, Anke; Bunzel, Wolfgang; Ceuppens, Jan et al

E-print/Working paper (2012)

Detailed reference viewed: 6 (0 ULg)