An exact solution method for the capacitated item-sharing and crowdshipping problem

The item-sharing and crowdshipping problem combines two concepts of the sharing economy, namely item-sharing and crowdshipping. Item-sharing is about renting items among members of a sharing community. Crowdshipping addresses the transportation of these items through private people on trips they make anyway. The considered problem is to decide (1.) which request for an item to fulfill through which of the supplied items and (2.) who is doing the transport of rented items from the supply-locations to the request-locations. We generalize this problem with regard to crowdshippers’ capacity, meaning that each crowdshipper can transport a given number of items along his/her intended route. This results in a detour routing problem, where crowdshippers are routed through intermediate locations on the way from their actual origin location to their intended destination. We propose an exact solution method based on a set packing formulation for which a label setting procedure generates feasible crowdshipper routes a priori. We also describe how to derive a heuristic from the exact approach. Our experiments identify to what extend higher capacities of crowdshippers lead to more profitable routes and under which conditions a heuristic reduction of the method is required to cope with the complexity of the problem. We also show that the new exact method clearly outperforms procedures that were developed earlier for a setting where each crowdshipper can transport at most one single item.