An efficient genetic algorithm for the uncapacitated single allocation hub location problem

Hub location problem is a NP-hard problem that frequently arises in the design of transportation and distribution systems, postal delivery networks, and airline passenger flow. We propose a simple but effective genetic algorithm (GA) for the uncapacitated single allocation hub location problem (USAHLP). Our main contribution is two new simple chromosome encoding schemes based on indirect representation and two crossover operators. We performed an empirical study to evaluate the effectiveness of the proposed GA using well-known benchmark problems from the Civil Aeronautics Board (CAB) and Australian Post (AP) data sets. The GA found all best-known solutions for the 80 CAB problems and introduced new solutions for the larger problem instances for AP data. The proposed GA can easily be extended to other variants of location problems arising in network design planning in transportation and distributed systems.