Numerical Experiments with AMLET, a New Monte-Carlo Algorithm for Estimating Mixed Logit Models Fabian Bastin,Cinzia Cirillo, Philippe L. Toint GRT, Dept Maths, FUNDP, Namur Report 03/10 Researchers and analysts are increasingly using mixed logit models for estimating responses to forecast demand and to determine the factors that affect individual choices. These models are interesting in that they allow for taste variations between individuals and they do not exhibit the independence from irrelevant alternatives property. However the numerical cost associated to their evaluation can be prohibitive, the inherent probability choices being represented by multidimensional integrals. This cost remains high even if Monte-Carlo techniques are used to estimate those integrals. This paper describes a new algorithm that uses Monte-Carlo approximations in the context of modern trust-region techniques, but also exploits new results on the convergence of accuracy and bias estimators to considerably increase its numerical efficiency. Numerical experiments are presented for both simulated and real data. They indicate that the new algorithm is very competitive and compares favourably with existing tools, including quasi Monte-Carlo techniques based on Halton sequences.