Current track allocation methods are poor proxies for welfare optimality and the traffic allowed by the resulting timetables therefore generate less welfare than would be possible under a better system. Willingness-to-pay based allocation such as auctions would lead to a more efficient use of the infrastructure in many cases, since it reveals operators’ own valuation of track access and incentivises frugality in capacity usage. It would also increase transparency, thus fostering competition in the market. But introducing a system that is so different from current practice is risky, since any unforeseen problem could potentially mean that no feasible timetable is ready for use in time. Alas, the implications of introducing track capacity allocation by auction must be studied on beforehand.

Addressing this, a number of serious games of a track slot auction were set up. We tested feasibility issues, which is not easily done by other means. Auctions can potentially be very complex, with each bid being a function of departure time, travel time and connections. Are operators able to place bid in their own self-interest? Are they able to adapt their strategy to account for different competitive circumstances and the unique characteristics of their own firm?

There is also the risk of systemic failure. The auction might result in an inefficient or infeasible timetable. Perhaps the auction can be ‘gamed’ so that one operator wins but the overall result is inefficient. The auction might not be properly concluded in a reasonable number of rounds, so it must either be terminated prematurely or continue when the timetable should already have been done.

The participants were selected for their industry knowledge. They were all employees of the Swedish infrastructure manager Trafikverket and had roles including key account manager and capacity analytic for railways. Several had previous experience of working at train operators as timetable coordinators and in other roles. The participants therefore understood the tasks before them, while being ‘neutral’ in terms of the competitive situation between operators. In the games, the participants took the role of train operator and bid for departure slots.