When planning their daily commute, most drivers account for the traffic they know is unavoidable: at peak times of day, like morning and afternoon rush hour, they probably allow extra time to get where they’re going.
The delays that are harder to accept are the unexpected ones, when accidents, road work, or a traffic bottleneck turn a thirty minute trip into an hour.
This unpredictable postponement leads to natural frustration on the part of drivers, as it may cause them to be late to work or late picking up children from school. A reliable road network is one in which this is a rare occurrence.
A project led by Portland State University’s Miguel Figliozzi explored the value of this travel-time reliability using a study of commuters’ route choice behavior, taking a look at the trade-offs between reliability, traffic congestion, and air pollution.
The details for the combined project can be found here.
In the first phase of the research, co-investigators David Levinson and Kathleen Harder of the University of Minnesota sought to measure the route choices drivers made in a real-world setting. Instead of just having people fill out a survey about whether they would choose to take major roads or the freeway to work, this study ambitiously placed GPS units in the cars of...Read more