"Allocating equitable parliamentary seating using mathematical optimization: A case study on Dáil Éireann, the Irish parliament."
The fair allocation of parliamentary seats to political parties is a challenge which arises in legislative chambers the world over. The application of mathematical optimization to address this type of problem is relatively novel. Existing research has focused primarily on the development of heuristic approaches to solve large chamber instances. Promising results have been found for simple problems, but no existing model could robustly incorporate the nuanced seating rules that are present in many parliamentary settings. This paper first evaluates several candidate exact approaches for small and medium-sized parliaments, finding that a Facility Location Model (FLM) is appropriate for chambers of under 200 seats. Secondly, a Location-Allocation Heuristic (LAH), already proposed in the literature for simple problems in larger settings, is revised to allow for the inclusion of intricate seating customs. These two models - exact and heuristic - are evaluated against historical electoral datasets for the Irish parliament. They are found to provide robust solutions, and persuasive evidence is presented for their practical adoption in alternative legislative chambers.
This repository contains the technical component of my master's thesis. It primarily contains code written in Xpress Mosel, a language developed for the Xpress Optimization Solver.
The data folder contains two subfolders: generated, which contains .... and historical, which contains ...