Search results for "Districting"
showing 3 items of 3 documents
Branch-Price-and-Cut for the Soft-Clustered Capacitated Arc-Routing Problem
2021
The soft-clustered capacitated arc-routing problem (SoftCluCARP) is a variant of the classical capacitated arc-routing problem. The only additional constraint is that the set of required edges, that is, the streets to be serviced, is partitioned into clusters, and feasible routes must respect the soft-cluster constraint, that is, all required edges of the same cluster must be served by the same vehicle. In this article, we design an effective branch-price-and-cut algorithm for the exact solution of the SoftCluCARP. Its new components are a metaheuristic and branch-and-cut-based solvers for the solution of the column-generation subproblem, which is a profitable rural clustered postman tour …
Solutions for districting problems with chance-constrained balancing requirements
2021
Abstract In this paper, a districting problem with stochastic demands is investigated. The goal is to divide a geographic area into p contiguous districts such that, with some given probability, the districts are balanced with respect to some given lower and upper thresholds. The problem is cast as a p -median problem with contiguity constraints that is further enhanced with chance-constrained balancing requirements. The total assignment cost of the territorial units to the representatives of the corresponding districts is used as a surrogate compactness measure to be optimized. Due to the tantalizing purpose of deriving a deterministic equivalent for the problem, a two-phase heuristic is d…
Seat Competitiveness and Redistricting: Evidence from Voting on Municipal Mergers
2013
We analyze how (anticipated) changes in the competitiveness of the seats of municipal councilors affect their voting behavior over municipal mergers. The competitiveness of the seats changes because the merger changes the composition of political competitors and the number of available seats in the next election. We use this variation for identification and find that the smaller the increase in the competitiveness of a councilor's seat, the more likely he is to vote for the merger. These effects are not related to the behavioral responses of the voters, but arise from the councilors’ desire to avoid electoral competition.