Université de Liège.
Agenda :
Titles, abstracts and documents :
May, Friday 11: Learning Consumer Tastes through Dynamic Assortments, by Pr. Dorothée Honhon (TU/e Technische Universiteit Eindhoven) (N1, room 115, 3:00pm-4:00pm)
Abstract : How should a firm modify its product assortment over time when learning about consumer tastes? In this paper, we study dynamic assortment decisions in a horizontally differentiated product category for which consumers’ diverse tastes can be represented as locations on a Hotelling line. We presume that the firm knows all possible consumer locations, comprising a finite set, but does not know their probability distribution. We model this problem as a discrete time dynamic program; each period, the firm chooses an assortment and sets prices to maximize the total expected profit over a finite horizon, given its subjective beliefs over consumer tastes. The consumers then choose a product from the assortment that maximizes their own utility. The firm observes sales, which provide censored information on consumer tastes, and updates beliefs in a Bayesian fashion. There is a recurring tradeoff between the immediate profits from sales in the current period (exploitation) and the informational gains to be exploited in all future periods (exploration). We show that one can (partially) order assortments based on their information content and that in any given period the optimal assortment cannot be less informative than the myopically optimal assortment. This result is akin to the well-known ‘stock more’ result in censored newsvendor problems with the newsvendor learning about demand through sales when lost sales are not observable. We demonstrate that it can be optimal for the firm to alternate between exploration and exploitation, and even offer assortments that lead to losses in the current period in order to gain information on consumer tastes. We also develop a Bayesian conjugate model that reduces the state space of the dynamic program and study value of learning using this conjugate model.April, Wednesday 23: Micro econometric evidence of financing frictions and innovatice activity, by Dr. Amaresh Tiwari (HEC-ULg) (N1, room 320, 12:00pm-2:00pm)
April, Friday 20: Conceptualizing organizational change toward corporate social responsibility: A quad-motor theory, by Pr. François Maon (IESEG School of Management Lille) (N1, room 223, 12:30pm-2:00pm)
Abstract : This article introduces a composite model of organizational change that moves toward corporate social responsibility (CSR), built on a combination of ideal-type theories of change and an existing conceptualization of CSR cultural phases. The result is a quad-motor theory of CSR development in which life cycle, teleological, dialectical, and evolutionary motors of change operate interdependently, depending on the unit of change considered and the level of integration of CSR principles into the company’s culture. This conceptual study supports more comprehensive accounts of the dynamic processes of organizational change toward CSR; it also helps bridge the gap between emerging research into what prompts corporate engagement in CSR and the actual design and implementation of CSR initiatives. Overall, this study offers both a relevant framework for assessing prior research and a structured blueprint to drive ongoing research efforts.March, Wednesday 21: Do Implicit Barrier MAtter for Globalization?, by Pr. Francesca Carrieri (McGill University, Montreal, Canada) (N1, room 220, 12:30pm-2:30pm)
Abstract : Market liberalization may not result in global pricing or full market integration if implicit barriers are important. We test this proposition for 22 emerging markets using the conditional version of Errunza and Losq (1985) model. We estimate and compare the degree of integration for stocks that are eligible for purchase by foreigners (investible) and those that are not (non-investible). Our results show that local factors are priced for both segments and the implicit barriers are significantly associated with the integration measure. Specifically, better institutions, stronger corporate governance and more transparent markets would jointly contribute to a higher degree of integration by about 15-20 percent.December, Thursday 7: Three Types of Competitive Facility Location Problems, by Phd. Hande Küçükaydin (ULg) (N1, room 320, 11:00-13:00)
December, Thursday 1: Coordination, Delegation and Organization of Shared Supply Chain Investments under Asymmetric Information, by Pr. Per Agrell (UCL) (N1, room 220, 10:00-12:00)
November, Thuesday 10: Testing for jumps in GARCH models, a robust approach by Pr. Franz Palm (Maastricht University) (N1, room 220, 12:00-14:00)
Abstract : Financial series occasionally exhibit large changes. Assuming that the observed return series consist of a standard normal ARMA-GARCH component plus an additive jump component, we propose a new test for additive jumps in an ARMA-GARCH context. The test is based on standardised returns, where the first two conditional moments are estimated in a robust way. Simulation results indicate that the test has very good finite sample properties, i.e. correct size and much higher proportion of correct jump detection than Franses and Ghijsels’s (1999) test. We apply our test on the YEU-USD exchange rate and find twice as much jumps as Franses and Ghijsels’s (1999) test.October, Monday 24: Optimisation de la gestion des opérations d'escale sur une plateforme aéroportuaire by Dr. Catherine Mancel (Ecole Nationale de l'Aviation Civile, Toulouse) (N1, room 315, 10:00-12:00)
Abstract : On s’intéresse au problème de la gestion des activités d’escales sur une plateforme aéroportuaire. Les opérations d’escale sont réalisées par différents prestataires de services, à l’aide de véhicules propres à chaque type d’opération. Ces différents intervenants doivent se coordonner de façon à réaliser les escales de chaque avion dans le temps imparti, tout en respectant les contraintes d’ordonnancement des tâches pour chaque avion et les contraintes liées à l’utilisation des véhicules de service. Or, on constate qu’une part importante des retards des vols est générée pendant l’escale des avions à leur poste de stationnement, il est donc intéressant d’étudier ce problème pour tenter de trouver des stratégies permettant de minimiser ces retards. Le problème d’optimisation combinatoire sous-jacent est un problème hybride d’ordonnancement de tâches et de tournée de véhicule qui, à notre connaissance, est très peu étudié dans la littérature. On propose un modèle mathématique puis on explore différentes pistes de résolution en s'appuyant sur une étude comparative de notre problème avec des problèmes académiques. Nous discuterons également du problème de la génération de jeux de données pertinents, nécessaires pour pouvoir évaluer les méthodes de résolution envisagées.May, Tuesday 17: Optimizing cost and quality of service in dial-a-ride operations by Prof. Gilbert Laporte (HEC Montréal) (N1, room 138, 14:00-16:00)
Abstract : In dial-a-ride problems, the aim is to design pickup and delivery routes for users wishing to be transported between given origins and destinations. These routes are subject to several operational constraints and must also take user inconvenience into account. We will present a tabu search multicriteria algorithm capable of incorporating operational costs and quality of service for users.
This work is derived from Julie Paquette's Ph.D. thesis, codirected by Gilbert Laporte and Jean-François Cordeau. François Bellavance and Marta M. B. Pascoal also took part in this research.May, Monday 10: Stratégies de Mutualisaion en Logistique urbaine by Prof. Frederic Semet (LAGIS, Ecole centrale de Lille, France) (N1, 13:00-14:30)
Abstract : La croissance de la congestion des infrastructures routières, en particulier dans les zones urbaines, est préoccupante et impose de trouver des solutions à la productivité générale de la filière logistique. Au niveau des pratiques actuelles du secteur logistique, on observe que: de nombreux trajets routiers se font à vide; de nombreux entrepôts ont des capacités de stockage non utilisées; les échanges intermodaux sont faibles; des capacités de transports de type ferrées (RER, métros de nuit) ou voies navigables sont sous-utilisées. Les fonctions d'échanges de fret ou de capacités de fret sont assurées par des bourses qui se limitent à la mutualisation ponctuelle du fret routier sur une partie du trajet. Elles permettent uniquement aux transporteurs de trouver de la marchandise pour éviter les retours à vide. Afin d'améliorer leur rentabilité, les entreprises de services disposant d'une capacité fixe essayent souvent d'augmenter leur taux d'occupation. Une sous-exploitation de la capacité disponible présente un coût excédentaire. La performance de l'entreprise est donc directement affectée par la gestion de la capacité.
Valoriser les surcapacités des infrastructures logistiques, massifier les flux et créer de la valeur avec les capacités vacantes en les mutualisant avec d'autres entreprises, devient un défi stratégique pour les entreprises. Dans cette présentation, nous présentons une solution de mutualisation des moyens non utilisés entre l'ensemble des acteurs de la chaîne logistique urbaine. Via une plateforme de communication logicielle, les acteurs en demande ou en offre de capacité de stockage ou de transport sont mis en relation. La plateforme est en charge de la planification opérationnelle de l'acheminement de la demande étant donné un réseau d'offres. Elle permet aux entreprises logistiques de faire des espaces vacants affectant leurs espaces de stockage et leurs moyens de transport de biens une source de création de valeur.
Plus spécifiquement, nous montrons comment un réseau d’offres de stockage et de transport peut être construit à partir des déclarations des capacités résiduelles disponibles soit pour le stockage temporaire soit pour le transport. Nous décrivons ensuite le modèle d’allocation des demandes sur ce réseau d’offres. Nous présentons finalement diverses extensions permettant d’une part de gérer des demandes de transport complexes et d’autre part d’accepter et d’allouer des demandes ponctuelles de façon à maximiser le revenu.
May, Monday 2: An Introduction to Statistical Process Control by Dr. Alireza Faraz (Postdoctoral researcher at HEC-ULg) (room 223, N1, 10:00-12:00)
Abstract : TQM is an integrative philosophy of management for continuously improving the quality of products and processes. It is used around the world. TQM functions on the premise that the quality of products and processes is the responsibility of everyone who is involved with the creation or consumption of the products or services offered by an organization. In other words, TQM capitalizes on the involvement of management, workforce, suppliers, and even customers, in order to meet or exceed customer expectations. In this seminar we introduce the TQM philosophy and then Statistical Process control subject, especially control charts as the most important tool in TQM.March, Thursday 3: Governance, legitimacy and performance in UK social entreprises by Chris Comforth (Open University business School) (Salle du Conseil, B31, 12:30-14:00)
Abstract :
1. The social enterprise sector in the UK - give a quick overview and discuss the problems of defintion
2. Origins of social enterprises - Look at the main routes to becoming a social enterprise
3. What is governance? - explain what I mean by governance and the governance system
4. Legal forms, governance structures and accountability - explain the different legal form SEs take and the implications for governance and accountability
5. Other forms of ensuring legitimacy and accountability - briefly mention other ways of trying to ensure legitimacy e.g. standards and cerfications
6. Governance and performance - discuss the link between governance and performance and why it is difficult to attribute causality
7. Governance challenges - discuss briefly some of the governance challenges faced by different types of SE.February, Monday 28: Route and fleet design for the cyclic inventory routing problem by Prof. Birger Raa (015, N1, 10:30-12:00)
Abstract : A well-known concept for supply chain integration is Vendor Managed Inventory (VMI), in which the distributor takes the responsibility for deciding on the timing and quantities with which its customers are replenished. Under VMI, the distributor is confronted with an Inventory Routing Problem (IRP) in which the inventory management of the customers is jointly optimized with the design of the distributor's vehicle routes that perform the replenishments. The assumption is made that demand rates at the customers are constant and therefore the cyclic inventory routing problem is considered. This problem consists of designing the vehicle routes that are to be cyclically repeated to replenish all customers, and designing schedules for the vehicle fleet that indicate which vehicle has to make which routes on any given day. Solution approaches for both subproblems will be presented and evaluated. Finally, the assumption of constant demand rates will also be put in perspective.November 2010, Tuesday 23: The valve location problem in simple network topologies by Dr. Alexander Grigoriev (Maastricht University) (Room 311, XVIIIth century Building, Rue Louvrex 14, 14:00-16:00),
Abstract : To control possible spills in liquid or gas transporting pipe systems, the systems are usually equipped with shutoff valves. In case of an accidental leak these valves separate the system into a number of pieces limiting the spill effect. In this work, we consider the problem, for a given edge-weighted network representing a pipe system and for a given number of valves, to place the valves in such a way that the maximum possible spill, i.e. the maximum total weight of pieces, is minimized. We investigate the complexity of the problem and develop the algorithms for several practical special cases.November 2010, Friday 19: Pseudo compact reformulation for the resource allocation problem by Fabio Furini (Ph.d student University of Bologna) (Room 223, N1 Building, Rue Louvrex 14, 15:00-16:00),
Abstract : The Resource Allocation Problem (RAP) is an NP- hard problem which introduces a temporal dimension in classical Knapsack Problems. RAP seeks the most prfitable subset of n given tasks which are not allowed to exceed the the amount of usable resource at any time. Each task has a pre-determined profit, a start and afinish time and a resource requirement. A classical Integer Linear Programming (ILP) formulation from the literature models the problem by associating a binary variable to each task, in order to dfine which tasks are selected. We propose a pseudo-compact reformulation in order to strengthen this descriptive model. The reformulation imposes the limit of resource usage by introducing new binary variables, each variable being associated to a feasible subset of tasks which are simultaneously active. These variables, whose number is exponential with respect to the problem size, are efficiently managed by means of a column generation approach. The generation of new variables derives from the solution of a series of knapsack problems. The continuous relaxation of this model is systematically stronger than the relaxation of the descriptive model. Finally, in order to obtain integer solutions, we embed our column generation procedures in a branching scheme, where we branch on the binary variables of the original formulation. We conclude by presenting computational results on a set of random instances.November 2010, wednesday 10: Coloring graphs while avoiding monochromatic cycles by F. Talla Nobibon (University of Leuven) (Room 311, XVIIIth century Building, Rue Louvrex 14, 13:00-14:00),
Abstract : We consider the problem of deciding whether a given directed graph can be vertex partitioned into two acyclic subgraphs. Applications of this problem include testing rationality of collective consumption behavior, a subject in microeconomics. We prove that the problem is NP-complete, even for oriented graphs and argue that the existence of a constant-factor approximation algorithm is unlikely for an optimization version which maximizes the number of vertices that can be colored using two colors while avoiding monochromatic cycles. We present three exact algorithms, namely an integer-programming algorithm based on cycle identification, a backtracking algorithm, and a branch-and-check algorithm. We compare these three algorithms both on real-life instances and on randomly generated graphs. We find that for the latter set of graphs, every algorithm solves instances of considerable size within few seconds ; however, the CPU time of the integer-programming algorithm increases with the number of vertices in the graph while that of the two other procedures does not. For real-life instances, the integer-programming algorithm solves the largest instance in about a half hour while the branch-and-check algorithm takes about ten minutes and the backtracking algorithm less than five minutes. Finally, for every algorithm, we also study empirically the transition from a high to a low probability of a YES answer as function of the number of arcs divided by the number of vertices.November 2010, thursday 4: Bootstrap Methods for Finance: Review and Analysis by Philippe Cogneau (Ph.D student HEC-Ulg), joint work with Valeri Zakamouline (University of Agder, Norway) (Room 315, XVIIIth century Building, Rue Louvrex 14, 12:00-13:30)
Abstract : In finance one often needs to estimate the risk and reward of an asset over a long-run given a sample of observations over a short-run. Two common obstacles in these estimations are a lack of suficient data and the uncertainty in the nature of the data generating process. To overcome the first obstacle the researches rely on statistical bootstrap methods. A practical realization of a bootstrap method depends crucially on whether the data are assumed to be serially dependent or not. In this paper we review some popular bootstrap methods and argue that the application of these methods is not well understood. This especially concerns the application of a moving block bootstrap method, which is used if there is a serial dependency in data. Namely, the estimates provided by a moving block bootstrap method are generally biased. We demonstrate the estimation bias and propose a method of bias adjustment. Moreover, in this paper we also analyze the precisions of estimations provided by bootstrap methods. We show that the precision of estimation provided by the moving block bootstrap methods is rather poor, which means that one should be aware that the estimation risk is a big issue.October 2010, thursday 7: Flowshop Scheduling with Flexible Operations by Asst. Prof. Hakan Gültekin (TOBB University of Economics and Technology, Ankara) (Room 315, XVIIIth century building, Rue Louvrex 14, 12:00-14:00)
Abstract : In order to be successful in today's highly competitive market, the companies have to adapt to the environment in which they operate, be more flexible in their operations, and satisfy different market segments. For these purposes Flexible Manufacturing Cells (FMC) are installed and used in most of the manufacturing industries. Use of flexible systems brings many advantages together with new and important problems to be tackled. In this talk we will consider some of these problems. We will first consider a two-machine flowshop in which identical parts to be processed have “flexible” operations. These operations are flexible in the sense that they can be performed by either one of the machines. The objective is to determine the allocation of the operations to the machines in order to maximize the throughput rate. We will consider different scenarios in terms of number of parts to be produced as well as the buffer capacity in between the machines. Next we will talk about robotic flowshops in which the loading and unloading of the machines are performed by a robot. We will consider the case where the machines are flexible enough to perform different operations. We will talk about single criteria models that only maximize the throughput as well as bicriteria models which additionally minimize the manufacturing cost. Last part of the talk is devoted to future research directions.October 2010, friday 1: Vehicle Routing Problems with Loading Constraints Using Loading Infeasibility to effectively prune the solution space by Florence Massen (Phd student at the UCL) (Room 223, N1, 14:00-16:00)
Abstract : Vehicle Routing Problems have received a great deal of attention since as early as the 1960's. During the last decades research has focused on more complex variants, such as problems with time windows or with pickup and delivery. This talk will focus on the more recently proposed combination of routing and loading resulting in the complex Vehicle Routing Problem with Loading Constraints. In this variant each customer to visit is associated with a set of items. A Routing Problem needs to be optimized in order to minimize the total traveling distance and furthermore, for each route a Loading Problem needs to be solved. To produce an overall feasible solution a feasible loading needs to be found for each route in the solution. As the loading feasibility of a route depends on the set of customers in the route, as well as on the sequence in which they are visited, reaching loading feasibility and minimizing the total traveling distance may conict. In this talk we will address the different problem variants encountered in literature as well as the methods that have been introduced to solve them. We will then point out the disadvantages of the current techniques and present a new method addressing those disadvantages. The core idea of our approach is the use of constraints derived from loading infeasibility information gathered throughout the search. We exploit those constraints in a known combination of Local Search and Constraint Programming called Large Neighborhood Search, resulting in the effective reduction of the Routing Problem solution space.March 2010, thursday 25: Monocultural vs. Intercultural Negotiations: What is the difference? by Pr. S. Paul Verluyten (University of Antwerp), (17:00)
Abstract : This lecture first offers a presentation of modern negotiation techniques and how they are different from the traditional view on negotiations. This will be followed by a discussion about the “exportability” of Western negotiation style to other cultures in the world.Please notice that this seminar will be given in Dutch.December 2009, thursday 17: La contribution de la théorie de la régulation sociale à l'analyse de la responsabilité sociale des entreprises, par Mr André Sobczack (Audencia Nantes École de Management), (12:00-13:00)
December 2009, monday 07: On the use of the error distribution for testing model features in nonparametric regression by Pr Juan Carlos Pablo Fernández (University of Vigo, Spain), (Salle du Conseil, B31, 11:00-12:00)
Abstract : Testing procedures based on the estimation of the error distribution in nonparametric regression models have been proposed in the recent literature. In the first part of the talk, we will revise the general idea of those testing procedures and present some examples (tests for the parametric form of the regression function, comparison of regression curves, tests about the equality of error distributions, and tests for the parametric form of the variance function). In the second part of the talk we will present some extensions and new perspectives of this kind of tests. Firstly, we will show how censored data can be incorporated to these models. Secondly, we will briefly present an estimator of the error distribution with multiple covariates, and show how it can be employed to test for additivity. Finally, we will discuss a test for a multiplicative structure in a dependent data setup.October 2009, thursday 17: Financial and Economic Determinants of Firm Default, by Pr Marco Grazzi (LEM, Assistant Professor at Scuola Superiore Sant’Anna, Pisa - Italy)(Room:315-N1, 11:00-12:30)
Abstract : This paper investigates the relevance of financial and economic variables as determinants of firm defaults. Our analysis is not limited to publicly traded companies but extends to a large sample of limited liability firms. We consider size, growth, profitability and productivity together with a standard set of financial indicators. Non parametric tests allow to asses to what extent defaulting firms differ from the non-defaulting group. Bootstrap probit regressions confirm that economic variables play both a long and short term effect. Our findings are robust with respect to the inclusion of Distance to Default and risk ratings among the regressors.PAPER: http://www.lem.sssup.it/WPLem/files/2009-06.pdfOctober 2009, friday 09: Current Researches in Management Control and Performance Measurements: Experience from Finland, by Pr Erkki Laitinen from the University of Vaasa (Room:035-N1, 10:30-12:00)
Abstract : The purpose of the presentation is to give a rough and selective description of Management Accounting (MA) research from the perspective of Finnish research. The focus of the presentation is on performance measurement (PM) systems. First, a classification of MA research on the basis of methodology applied is presented. Then, a short description of MA research activities in Finland is followed. The main research methodologies of a few researchers are briefly outlined. The rest of presentation time is taken to present examples of Finnish MA studies.These exemplary studies are based on different methodologies but are all focused on performance measurement (PM).September 2009, tuesday 29: Complementary comptences and inter-firm ambidexterity, by Despoina Filiou, senior lecturer in Strategic Management at the Manchester Metropolitan University Business School. (Lentic (B51), 09:30-11:00)
Abstract : We address an under researched issue; the importance of complementary inter-firm competences in ambidextrous cooperation agreements. New biotech start-ups and established pharma firms have an incentive to cooperate in order to explore each other’s scientific and demand orientated competences. Long term competitiveness requires both types of competences. Principal components analysis of 2,024 cooperative agreements shows firms develop ambidextrous portfolios which interrelate exploration agreements and exploitation agreements across demand-orientated domains and scientific domains. The findings have important implications for ambidexterity in other sectors with high rates of scientific/technological change.August 2009, wednesday 26 : Vehicle loading optimization with stochastic supply - models, by David Kronus, visinting researcher of QuantOM, HEC-ULg. (B31, 11:00 AM)
August 2009, friday 28 : Vehicle loading optimization with stochastic supply - implementation in AIMMS, by David Kronus, visinting researcher of QuantOM, HEC-ULg. (B31, 14:00 AM)
Abstract : In this technical presentation we describe our implementation of solution techniques based on the deterministic and stochastic models introduced in the previous seminar. We present a project in AIMMS which contains the implementation and we focus on features related to stochastic aspects of the model. In particular we explain in detail how scenarios can be generated in AIMMS using a built-in support module and how scenario-based deterministic equivalent of a stochastic model can be automatically created. Part of the implementation in AIMMS is also a testing framework which we use to evaluate the performance of the indiviual solution techniques.
June 2009, wednesday 24 : Operations research methods for electricity markets, by Yves Langer, HEC-ULg and Belpex (Séminaire 11 -B31, 12:00-14:00)
June 2009, monday 15 : Constraint programming: hands on COMET software, by Pierre Schaus, BeCool Group UCL (Medialab - B31, 9:00 - 12:00). Inscription required (attendants have to bring their laptop with COMET installed) : contact vanessa.rosso@ulg.ac.be.
June 2009, friday 5 : Innovation and Marketing Research Day (Salle du Conseil, 9:00 - 18:00) with scholars from Belgian and Dutch universities and
- Prof. Erik Hultink: Delft University
- Prof: Chantal De Morloose : Louvain la neuve
- Prof: Jhan Van Rekom : Rotterdam School of Management
- Prof Hans Ouwersloot :Maastricht University
- Prof: Sandra Strukens: Haaselt University
- Prof: Allard Van Riel: University of Liege
- Prof: Charles Pahud de Mortanges: University of Liege
June 2009, friday 5 : L’innovation sociale dans le modèle québécois : la part de la société civile , par M. Pr. Denis Harrisson, Directeur du CRISES – Centre de recherche sur les innovations sociales, UQAM – Université de Québec à Montréal, Québec (Trifac 3 - B33, 12:30 - 14:00). Séminaire conjoint avec la Chaire Cera en Entrepreneuriat et Management de l’Economie Sociale
May 2009, friday 15 : Risk indifference pricing and backward stochastic differential equations, by Xavier De Scheemaekere, Solvay Business School, ULB (334 - N1, 12:30 - 14:00)
May 2009, tuesday 12 :Market Liquidity as Dynamic Factors, by Charles Mathias, ULB (315-N1, 12:30 - 14:00)
May 2009, friday 8 : "So pensions in Europe will remain sustainable. But will they remain adequate?" by Raphael Desmet and Gijs Dekkers (Bureau du Plan). (TriFac 2, 13:30-15)
April 2009, Monday 20 : Dynamiques d'apprentissage inter-organisationnel : étapes critiques, enjeux et bonne pratiques, par Julie Degré (LENTIC) (12h00-14h00, SDC, B31)
March 2009, friday 27 : "Réduction de la pauvreté" , par F. Bourguignon (Directeur PSE). (9h00-12h00, Auditoire Laurent (B31)
February 2009, thursday 19 : Culturele verschillen in de zakenwereld: het geval België - Nederland, by Paul Verluyten, professeur à l'Universiteit Antwerpen et spécialisé en communication interculturelle (17h - 18h30, room 126, N1)
February 2009, wednesday 11 : Constraint Programming, Mathematical Programming and Local Search : the COMET Project, by Pascal Van Henteryck, Brown University, USA.(16h00-18h00, SDC, B31)
February 2009, thursday 5 : Règlementation et modèle de prévision de difficultués bancaires en zone CEMAC, par Duclaux Soupmo Badjio, HEC-ULg (12h30-14h, room 315, N1)
February 2009, tuesday 3 : Appointment Scheduling with Discrete Random Durations (abstract - presentation), by Maurice Queyranne, Sauder School of Business, Canada (14h30-16h, room seminaire12, B31)
December, friday 19 : Gender and entrepreuneurship, by Mrs. Teresa Nelson, Simmons School of Management, Boston, Massachusetts. (room 315 / N1, 9h - 13h)
abstract (in french : invitation):
Professor Nelson's recent research is focused on the intersection of gender and entrepreneurship and the project she will discuss involves the ways that successful women entrepreneurs perceive gender as a factor they must manage as they seek to acquire essential organizational resources. Nelson and her colleagues interviewed 20 women founder/CEOs in California and Massachusetts who had successfully accessed venture capital for their firms. The results of the research show how being a woman is relevant to women's entrepreneurial business success, and how women strategize and manage the gendered landscape. Nelson will also discuss generally the status of women entrepreneurs in the United States and the particular opportunities and challenges they face.December, monday 15 : Does Volatility matter? Expectations of price return and variability in an asset pricing experiment. Miss Francesca Pancotto, PhD. Scuola Superiore S. Anna, Pisa (f.pancotto@sssup.it). (local 315 /N1, 16:00 -18:00)
abstract: We present results of an experiment on expectation formation in an asset market. We consider a simple market with a riskless bond and a risky stock.
In the market, six experimental subjects must provide forecasts of the stock future return to computerized utility-maximizing investors, and are rewarded according to how well their forecasts perform in the market. We run two treatments to test the influence of perceived volatility on aggregate dynamics. In the Baseline treatment subjects must only forecast the stock future return one period ahead; in the Variance treatment, we also elicit subjects confidence intervals for their forecasts, which we take as a proxy for perceived volatility. The realized asset price is derived from a Walrasian market equilibrium equation with non-linear feedback from individual forecasts. Our experimental markets exhibit high volatility, fat tails and other properties typical of real financial data. Eliciting confidence intervals for predictions has the effect of reducing price fluctuations and increasing subjects' coordination on a common prediction strategy.December, thursday 4 : Global Sourcing Strategies and Their Impacts on the Supplier Performance & Innovation. by M. Aydin INEMEK, PhD, Dokuz Eylul University. (ainemek@yahoo.com) au séminaire 3 (B31) de 13h à 15h30.
abstract: Intense competitive pressures, in the global markets, have forced companies to find and select new supply sources in the worldwide for reducing cost and improving quality while simultaneously achieving high technology in the long term. On the other hand, realizing the impacts of suppliers and supplier relationships on the firm’s performance and competitiveness has motivated firms to develop long-term strategic sourcing relationships with suppliers. The purpose of this study is to examine global sourcing relationships and to investigate the impacts of global buyers’ sourcing strategies on the supplier performance and innovation. ...
November, thursday 20 : On the price elasticity of demand for patents
by Gaétan de Rassenfosse, FNRS Research Fellow, ULB, Solvay Brussels School of Economics and Management (SBS-EM), ECORE (ECARES) and Bruno van Pottelsberghe de la Potterie, ULB, Solvay SA Chair of Technological Innovation, SBS-EM, ECORE (ECARES), Bruegel, Brussels and CEPR, London
presented by Gaétan de Rassenfosse.November, thursday 13 : A closer look at the relationship between life expectancy and economic growth, by Theophile Azomahou (Maastricht)(13:30 – 15:00, room "séminaire 10")
abstract: We first provide a nonparametric inference of the relationship between life expectancy and economic growth on an historical data for 18 countries over the period 1820-2005. The obtained shape shows up convexity for low enough values of life expectancy and concavity for large enough values. We then study this relationship on a benchmark model combining “perpetual youth" and learning-by-investing. In such a benchmark, the generated relationship between life expectancy and economic growth is shown to be strictly increasing and concave. We finally examine two models departing from “perpetual youth" by assuming successively age-dependent earnings and age-dependent survival probabilities. With age-dependent earnings, the obtained relationship is hump-shaped while agedependent survival laws do reproduce the convex-concave shape detected in the prior empirical study.
November, thursday 6 : Correlation between the Recovery Rate and the Arrival Rate of Default. Application on the iTraxx. Join work with G. Hübner, presented by Jean Roch Sybille (HEC-ULg).
abstract:We study the effect of the relationship between the recovery rate (RR) and the probability of default (PD) in the traditional Monte Carlo credit risk model introduced by Li (1999) for the pricing of structured credit derivatives. The influence of this effect is particularly important if we consider extreme tranches of CDOs, because they are only reached when numerous defaults have arrived. This could be an explanation of the observed correlation smile on the market. The model is applied on a generic cash CDO and on the European iTraxx synthetic CDO index.
October, thursday 23 : (EC) Residential Segregation and Unemployment: The Case of Brussels, by Claire Dujardin (UCL). (13:30 – 15:00, room "séminaire 10")
abstract: This paper investigates the causal effects of the spatial organization of Brussels on unemployment propensities. Using Census data at the individual level, we estimate the unemployment probability of young adults while taking into account personal, household and neighbourhood characteristics. We solve the endogeneity of residential locations by restricting our sample to young adults residing with their parents, and evaluate the potential remaining bias by conducting a sensitivity analysis. Our results suggest that residing in a deprived neighbourhood significantly increases a youngster probability of being unemployed, a result which is quite robust to the presence of both observed and unobserved parental covariates.
October, thursday 16 : Explaining returns on venture capital backed companies: evidence from Belgium! Yan M. Alperovych and Georges Hübner, HEC-ULg Management School - University of Liège , presented by Yan Alperovych (12:30, room315,N1)
October, monday 6 : Interval representations of Boolean functions, presented by David Kronus, Post-Do student at HEC-ULg (12h30, Salle du Conseil,B31)
abstract: Boolean function on n variables is a mapping of Boolean vectors of length n to Boolean values (Boolean vectors contain just Boolean values 0,1, traditionally denoted as false and true). Boolean functions can be represented in many ways, the most usual forms are logical formulae and decision trees. One of the fundamental problems in the field of Boolean function is Boolean minimization where the task is to find a short representation of a given function. In my talk I will present a non-traditional representation of Boolean functions – the interval representation, its properties and relation to Boolean minimization.
Guillaume Amand
(Thèmes Operations)
guillaume.amand@ulg.ac.be
tel +32 4 3663192Laurent Bodson
(Thèmes Finance)
Laurent.Bodson@ulg.ac.be
tel. +32 4 2327431Lutgarde Nachtergale
(Thèmes Langues)
Lutgarde.Nachtergaele@ulg.ac.be
tel +32 4 2327278Joseph Tharakan
(Thèmes Economie)
J.Tharakan@ulg.ac.be
tel +32 4 3663121