ORBi Open Repository and Bibliography
In may 2007, the ULg's Administrative Board (joined in June 2007 by the FUSAGx) decided to create an institutional repository and defined a strong institutional self-archiving policy to increase the visibility, accessibility and impact of the University's publications (Board's decision).
This decision led to the official launch, in November 2008, of the ORBi platform including both the Academic Bibliography and the Institutional Repository of the Wallonia-Europe University Academy.
Business & economic sciences => Quantitative methods in economics & management
Continuous Departure Time of Day Preferences for Continental U.S. Airline Markets Segmented by Distance, Direction of Travel, Number of Time Zones, Day of Week and Itinerary Type - Lurkin, Virginie; Garrow, Laurie; Higgins, Matthew; Newman, Jeffrey; Schyns, Michael
Airlines use itinerary choice models to allocate the total number of passengers in a city pair to specific itineraries. In a related paper, we estimated a multinomial logit (MNL) itinerary choice model using database of more than 3 million tickets for Continental U.S. markets provided by the Airlines Reporting Corporation that accounted for price endogeneity. The size and comprehensiveness of our database allowed us to estimate highly refined continuous departure time of day preference curves that account for distance, direction of travel, the number of time zones traversed, departure day of week and itinerary type (outbound, inbound or one-way). This...
Comment réduire l'impact environnemental pour le transport de marchandises ? - Limbourg, Sabine
Avec l'internationalisation des activités économiques, la demande de transport a considérablement augmenté suite à l’allongement des distances et à la multiplication des fréquences d’envois. Pour répondre aux exigences du e-commerce et des livraisons à domicile, de nouveaux schémas logistiques sont indispensables. Ces défis doivent être relevés tout en minimisant les nuisances environnementales. A l'occasion de ce lunch-conférence, Sabine Limbourg exposera le résultat de ses recherches, basées sur des méthodes quantitatives, explorant trois options permettant de réduire l'impact environnemental pour le transport des marchandises. Ces options sont le transport intermodal qui combine efficacement plusieurs modes de transport, l'intégration de véhicules électriques...
Quadratizations of pseudo-Boolean functions - Crama, Yves
A pseudo-Boolean function is a real-valued function of 0-1 variables. Every pseudo-Boolean function can be represented by various analytical expressions, e.g., as a polynomial in its variables, or as a polynomial in its variables and in their Boolean complements, or as a disjunctive form, or as pointwise minimum of a family of affine functions, and so forth.
Motivated by the problem of minimizing pseudo-Boolean functions, we consider yet another class of representations. Namely, we say that g(x,y) is a quadratization of the pseudo-Boolean function f(x) if g(x,y) is a quadratic pseudo-Boolean function of x and of m auxiliary binary variables y...
Revealed preference tests of collectively rational consumption behavior - Crama, Yves
To verify the empirical adequacy of a particular household consumption model, it is important to develop efficient tests did can be applied to real-world data. These tests check whether the observed household behavior is "rational" in the sense that it is consistent with the predictions of the model. In this talk, we present different approaches based on revealed preferences to test collective models of household consumption. Testing collective rationality is computationally difficult (NP-hard). In order to overcome this negative result, we introduce mixed-integer programming formulations which can be used for medium-sized datasets. Next, we propose simulated annealing heuristics, which allow...