Large-scale agent-based travel demand optimization applied to Switzerland, including mode choice

Abstract

This paper presents the application of the agent-based transport simulation toolkit MATSim-T to
a large-scale scenario of Switzerland. The scenario is called large-scale because ca. 6 million
synthetic persons, “agents”, are simulated on a high-resolution network model with >1 million
links. MATSim-T is able to compute a relaxed state of the simulation system within 60 iterations
of the learning-based solution procedure with regard to mode choice, car route choice and
choice of activity timing. This is achieved by applying improved optimization algorithms in the
replanning stage. A genetic algorithm is used for times and and mode choice optimization of
activity plans, together with an efficient implementation of time-dependent shortest path search
for route choice.

The improvements of the behavioral model reported in this paper are focused on the scoring
function which can process individualized parameters for measuring the quality of all-day activity
plans. Combined with disaggregate input data for population and land use, it was possible to
build a heterogeneous and thus more realistic scenario. Furthermore, four modes of transport
(car, public transit, bike, walk) are considered in the presented application. The generalized
cost of the car option is determined by a queue simulation of traffic flow. In order to prove
the concept of mode choice optimization in a multi-agent microsimulation, the other modes are
modelled as abstract alternatives with static travel costs constant throughout the modeled average
workday. It is shown how the model is calibrated against observed modal split data. The
results are validated with average workday count data. Despite the simple cost structure of the
mode alternatives, and due to a mode choice concept based on subtours, the observed spatial
distribution of the modal split can be reproduced within +/-10 percentage points per mode.

Document link

http://www.ivt.ethz.ch/vpl/publications/reports/ab625.pdf

Remarks

• The paper was also presented at the Integrated Modeling and Simulation Workshop of the MIT Portugal Program Transportation Systems focus area held in Lisbon, July 15-17, 2010. See slides below.
• The paper is an update of earlier Switzerland results described in this publication.