Modelling travel behaviour with OR tools: From microsimulation to 
fixed point problems

Kay Axhausen
ETH Zurich

Transport planning at the strategic and tactical level relies heavily 
on numerical assessments of the impacts, cost and benefits of 
a policy change or investment. At the core of most procedures are 
optimization tools which allow the planner to model these changes. 
The presentation will report on a number of challenges which arise, 
as one tries to model large systems in a useful time; both with 
regards to model implementation and later application. Typical system 
sizes are 106 agents in microscopic models or 5000 * 5000 zones 
matrizes for aggregate models. The presentation will focus on 
the on-going work on a large scale microsimulation model of 
dynamic travel demand, but will also report on the national 
travel demand model for Switzerland.