Based on the decision to file an escape clause petition by a firm, a Poisson regression model of the macroeconomic determinants of the total number of these petitions yearly is developed and estimated. The Poisson specification conforms to the fact that the number of escape clause petitions is a...

A flexible, generalized Poisson model is combined with the multinomial distribution to jointly predict households' choices among types of trips and frequency of trips. The model is compared with conventional Poisson models. The problem of a time-variant mean for frequencies is also addressed, as...