NCTSPM Seminar Dr. Laurie Garrow 11.03.2016 Part 1/3

Join NCTSPM for this Transportation Speaker Series event, featuring Dr. Laurie A. Garrow, Ph.D., Associate Professor of Civil and Environmental Engineering at Georgia Institute of Technology. Dr. Garrow will be speaking on the topic of "Estimation of Airline Itinerary Choice Models Using Disaggregate Ticket Data".

Airline itinerary choice models support many multi-million dollar decisions, e.g., they are used to evaluate potential route schedules. Classic models suffer from major limitations, most notably they use average fare information but to not correct for price endogeneity. We use a novel database of airline tickets to estimate itinerary choice models using detailed fare data and compare these to classic itinerary choice models that use aggregate fare information but correct for price endogeneity. In order to estimate these large itinerary choice models, we developed a new freeware program, called Larch. Benchmarking experiments against Stata and Biogeme showed that the size of the input estimation files are 50 to 100 times larger in Stata and Biogeme, respectively. Estimation times are also much faster in Larch; e.g., for a small itinerary choice problem, a multinomial logit model estimated in Larch converged in less than one second whereas the same model took almost 15 seconds in Stata and more than three minutes in Biogeme. For more complex discrete choice models, such as the ordered generalized extreme value model, estimation times were two seconds in Larch and four to five days in Biogeme.