A general and operational representation of GEV models

Generalised Extreme Value models provide an interesting theoretical framework to develop closed-form random utility models. Unfortunately, few instances of this family are to be found as operational models in practice. The form of the model, based on a generating function G which must satisfy speci c properties, is rather complicated. Fundamentally, it is not an easy task to translate an intuitive perception of the correlation structure by the modeller into a concrete G function. And even if the modeller succeeds in proposing a new G function, the task of proving that it indeed satis es the properties is cumbersome. The main objectives of this paper are (i) to provide a general theoretical foundation, so that the development of new GEVmodels will be easier in the future, and (ii) to propose an easy way of generating new GEV models without a need for complicated proofs. Our technique requires only a network structure capturing the underlying correlation of the choice situation under consideration. If the network complies with some simple conditions, we show how to build an associated ∗RAND Europe and Institute for Transport Studies, University of Leeds, UK. Email: [email protected] †Ecole Polytechnique F ed erale de Lausanne, Dpt. of Mathematics, CH-1015 Lausanne, Switzerland. Email: michel.bierlaire@ep .ch