Use Operations Research to Maximize Value in a Train Network

Lynne Kiesling

Check out this cool Financial Times article on Dutch use of operations research to optimize their train network and timetable.

Imagine trying to create a system detailing the precise movements of 5,500 daily train services, thousands of pieces of rolling stock and all the personnel needed to run a railway network (a typical day on the Dutch railway involves 15,000 driver journeys). Then figure that, as with a Rubik’s Cube, moving any piece of the puzzle could have knock-on effects on another part – meaning that the problem always has to be tackled as a whole, rather than in its component pieces.

Imagine, also, that the timetable must be flexible enough to withstand everyday disturbances and that it needs to strike a balance between operating costs and service quality. Quite complex.

This is a problem for operations research! The article then goes on to describe how academics, Netherlands Railways, and ProRail worked together to devise algorithms to come up with 10 alternative timetables, depending on the objective function that they wanted to maximize.

So far, so good:

The new timetable, introduced in December 2006, has been a success by a number of measures. Passenger demand has increased by 15 per cent on some lines. Passenger satisfaction, measured in surveys, has gone up. More trains arrive on time. And Netherlands Railways makes better use of its resources. Its profits rose by €40m ($61.8m) in the first year of the timetable, with more profit growth expected down the line.

But it was not a Pareto move, as we economists say; some passengers in some locations complain that their journeys are longer now with the new timetable.

The participants see this collaboration as a great example of academic and business interaction, with each one feeding into the other.