Abstract
We perform a shooting experiment for the knapsack facets and observe that 1∕k-facets are strong for small k; in particular, k dividing 6 or 8. We also observe spikes of the size of 1∕k-facets when k = n or when k + 1 divides n + 1. We discuss the strength of the 1∕n-facets introduced by Aráoz et al. (Math Program 96:377–408, 2003) and the knapsack facets given by Gomory’s homomorphic lifting.A general integer knapsack problem is a knapsack subproblem where a portion, often a significant majority, of the variables are missing from the master knapsack problem. The number of projections of 1∕k-facets on a knapsack subproblem of l variables is \(O(l^{\lceil k/2\rceil })\), note that this is independent of the size of the master problem. Since 1∕k-facets are strong for small k, we define the 1∕k-inequalities which include the 1∕d-facets with d dividing k and fix k to be a small constant such as k = 6 or k = 8. We develop an efficient way of enumerating violated valid 1∕k-inequalities. For each violated 1∕k-inequality, we determine its validity by solving a small integer programming problem, the size of which depends only on k.
Keywords
- Knapsack problem
- Master knapsack polytope
- Facets
- Shooting experiment
- Cutting planes
Mathematics subject classification (2010):
- 90C10 Integer Programming
This chapter was prepared for publication in MOPTA 2014 Proceedings.
This is a preview of subscription content, access via your institution.
Buying options


References
Aráoz, J.: Polyhedral neopolarities, Ph.D. Thesis, University of Waterloo, Department of Computer Science (1974)
Aráoz, J., Evans, L., Gomory, R., Johnson, E.: Cyclic group and knapsack facets. Math. Program. 96, 377–408 (2003)
Basu, A., Hildebrand, R., Köppe, M., Molinaro, M.: A (k + 1)-slope theorem for the k-dimensional infinite group relaxation. SIAM J. Optim. 23(2), 1021–1040 (2011)
Cornuéjols, G., Molinaro, M.: A 3 slope theorem for the infinite relaxation in the plane. Math. Program. Ser. A 142, 83–105 (2013)
Dash, S., Günlük, O.: Valid inequalities based on the interpolation procedure. Math. Program. 106, 111–136 (2006)
Evans, L.A.: Cyclic group and knapsack facets with applications to cutting planes. Ph.D. Thesis, Georgia Institute of Technology (2002)
Gilmore, P.C., Gomory, R.E.: The theory and computation of knapsack functions. Oper. Res. 14, 1045–1074 (1966)
Gomory, R.E.: Some polyhedra related to combinatorial problems. Linear Algebra Appl. 2, 451–558 (1969)
Gomory, R.E., Johnson, E.L.: Some continuous functions related to corner polyhedra. Math. Program. 3, 23–85 (1972)
Gomory, R.E., Johnson, E.L.: Some continuous functions related to corner polyhedra, II. Math. Program. 3, 359–389 (1972)
Gomory, R.E., Johnson, E.L.: T-space and cutting planes. Math. Program. 96, 341–375 (2003)
Gomory, R.E., Johnson, E.L., Evans, L.: Corner polyhedra and their connection with cutting planes. Math. Program. 96, 321–339 (2003)
Gupte, A.: Convex hulls of superincreasing knapsacks and lexicographic orderings. Manuscript. http://arxiv.org/abs/1503.03742 (2015)
Hunsaker, B.: Measuring facets of polyhedra to predict usefulness in branch-and-cut algorithms. Ph.D. Thesis, Georgia Institute of Technology (2003)
Kuhn, H. W.: Discussion. In: Proceedings of the IBM Scientific Symposium on Combinatorial Problems, 16–18 March 1964, IBM Data Processing Division, pp. 118–121. White Plains, New York (1966)
Shim, S.: Large scale group network optimization. Ph.D. Thesis, Georgia Institute of Technology (2009)
Shim, S., Johnson, E.L.: Cyclic group blocking polyhedra. Math. Program. 138, 273–307 (2013)
Shim, S., Chopra, S., Cao, W.: The worst case analysis of strong knapsack facets. Manuscript. www.researchgate.net/publication/263181439 (2014)
Shu, Y., Chopra, S., Johnson, E.L., Shim, S.: Binary group facets with complete support and non-binary coefficients. Oper. Res. Lett. 41, 679–684 (2013)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2015 Springer International Publishing Switzerland
About this paper
Cite this paper
Chopra, S., Shim, S., Steffy, D.E. (2015). A few strong knapsack facets. In: Defourny, B., Terlaky, T. (eds) Modeling and Optimization: Theory and Applications. Springer Proceedings in Mathematics & Statistics, vol 147. Springer, Cham. https://doi.org/10.1007/978-3-319-23699-5_4
Download citation
DOI: https://doi.org/10.1007/978-3-319-23699-5_4
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-23698-8
Online ISBN: 978-3-319-23699-5
eBook Packages: Mathematics and StatisticsMathematics and Statistics (R0)