Abstract
The Set Covering Problem (SCP) is NP-hard. We propose a new Row Weighting Local Search (RWLS) algorithm for solving the unicost variant of the SCP, i.e., USCPs where the costs of all sets are identical. RWLS is a heuristic algorithm that has three major components united in its local search framework: (1) a weighting scheme, which updates the weights of uncovered elements to prevent convergence to local optima, (2) tabu strategies to avoid possible cycles during the search, and (3) a timestamp method to break ties when prioritizing sets. RWLS has been evaluated on a large number of problem instances from the OR-Library and compared with other approaches. It is able to find all the best known solutions (BKS) and improve 14 of them, although requiring a higher computational effort on several instances. RWLS is especially effective on the combinatorial OR-Library instances and can improve the best known solution to the hardest instance CYC11 considerably. RWLS is conceptually simple and has no instance-dependent parameters, which makes it a practical and easy-to-use USCP solver. © 2015 Elsevier B.V. and Association of European Operational Research Societies (EURO) within the International Federation of Operational Research Societies (IFORS). All rights reserved.
Original language | English |
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Pages (from-to) | 750-761 |
Number of pages | 12 |
Journal | European Journal of Operational Research |
Volume | 246 |
Issue number | 3 |
Early online date | 23 May 2015 |
DOIs | |
Publication status | Published - Nov 2015 |
Externally published | Yes |
Keywords
- Combinatorial optimization
- Row weighting local search
- Unicost set covering problem