Optimizing on-demand feeder service areas via greedy spatial expansion: comparison with simple geometries

Abstract

Service areas in demand-responsive feeder systems are often defined using simple geometric shapes or existing administrative boundaries, without considering how their geometry affects system performance. This paper approaches service area design as a spatial decision problem and examines how different geometric assumptions influence operational outcomes. We propose a simulationbased optimization framework in which the service area is constructed iteratively by expanding the region based on its contribution to system performance. This allows us to compare the optimized configuration with commonly used ad-hoc geometries, including circular, rectangular, and administrative areas. The framework is demonstrated in a case study of a feeder service in the Skotniki district of Kraków, Poland. The results show that the optimization-driven configuration outperforms the baseline geometries in key performance indicators. This indicates that simple geometric shapes may lead to less efficient designs, and that service area geometry should be treated as a decision variable in the planning of demand-responsive feeder systems, rather than as a fixed construct.