A two stage stochastic optimization model for the Bike sharing allocation and rebalancing problem
The Bikesharing allocation and rebalancing problem is the problem of determining the initial daily allocation of bikes to stations in a bikesharing system composed of one depot and multiple capacitated stations, in which bikes can be rebalanced at a point in time later in the day. We propose a two stage stochastic programming formulation, where the allocation is made in the first stage and the recourse decisions related to rebalancing are made in the second stage. The impact of the stochastic demand on the problem solution is examined, showing the benefits of the proposed methodology with respect to the solution of the deterministic equivalent formulation. Nevertheless, we derive a deterministic solution based heuristic for solving the stochastic program that significantly reduces its solution time without losing solution quality. We benchmark our approach on the real bikesharing system of the city of San Francisco.