On hub location problems in geographically flexible networks Blanco Izquierdo, Víctor Puerto, Justo Hub location Mixed integer nonlinear programming Neighborhoods Network design The authors were partially supported by research groups SEJ-584 and FQM-331 (Junta de Andalucia) and projects MTM2016-74983-C02-01 (Spanish Ministry of Education and Science/FEDER), FEDER-US-1256951, P18-FR-1422, P18-FR-2369 (Junta de Andalucia), CEI-3FQM331 (Andalucia Tech), and NetmeetData (Fundacion BBVA - Big Data 2019). We also would like to acknowledge Elena Fernandez (Universidad de Cadiz) for her useful and detailed comments on previous versions of this manuscript. In this paper, we propose an extension of the uncapacitated hub location problem where the potential positions of the hubs are not fixed in advance. Instead, they are allowed to belong to a region around an initial discrete set of nodes. We give a general framework in which the collection, transportation, and distribution costs are based on norm-based distances and the hub-activation setup costs depend not only on the location of the hub that are opened but also on the size of the region where they are placed. Two alternative mathematical programming formulations are proposed. The first one is a compact formulation while the second one involves a family of constraints of exponential size that we separate efficiently giving rise to a branch-and-cut algorithm. The results of an extensive computational experience are reported showing the advantages of each of the approaches. 2021-06-01T10:59:49Z 2021-06-01T10:59:49Z 2021-05-19 info:eu-repo/semantics/article Blanco, V. and Puerto, J. (2021), On hub location problems in geographically flexible networks. Intl. Trans. in Op. Res.. [https://doi.org/10.1111/itor.12993] http://hdl.handle.net/10481/68972 10.1111/itor.12993 eng http://creativecommons.org/licenses/by-nc-nd/3.0/es/ info:eu-repo/semantics/openAccess Atribución-NoComercial-SinDerivadas 3.0 España Wiley-Blackwell Publishing