have a jointly normal distribution. No closed form for the cumulative distribution of normal distribution. Simulation necessary. 4. Mixed logit Allows any distribution in unobserved factors No closed form for the cumulative distribution of normal distribution. Simulation necessary. References A Nevo (2000). "Practitioners Guide to Estimation of Random Coefficients Logit Models of Demand," Journal of Economics & Management Strategy, 9(4), 513–548 Colombino, U. (2010). Equilibrium policy simulations with random utility models of labour supply, Carlo Alberto Notebooks 156, Collegio Carlo Alberto. Kenneth E. Train, " Discrete Choice Methods with Simulation", Massachusetts: Cambridge University Press, 2003. Choice modelling