Thomas Jatschka, Tobias Rodemann, Guenther Raidl, "A Large Neighborhood Search for a Cooperative Optimization Approach for Distributing Service Points in Mobility Applications", META2021 Conference, pp. 3-17, 2022.

We present a large neighborhood search (LNS) as optimization core for a cooperative optimization approach (COA) to optimize locations of service points for mobility applications. COA is an iterative interactive algorithm in which potential customers can express preferences during the optimization. A machine learning component processes the feedback obtained from the customers. The learned information is then used in an optimization component to generate an optimized solution. The LNS replaces a mixed integer linear program (MILP) that has been used as optimization core so far. A particular challenge for developing the LNS is that a fast way for evaluating the non-trivial objective function for candidate solutions is needed. To this end, we propose an evaluation graph, making an efficient incremental calculation of the objective value of a modified solution possible. We evaluate the LNS on artificial instances as well as instances derived from real-world data and compare its performance to the previously developed MILP. Results show that the LNS as optimization core scales significantly better to larger instances while still being able to obtain solutions close to optimality.