Abstract
Chapter 6 surveys a list of known tractable valued constraint languages. Quite strikingly, all of them can be characterised by simple fractional polymorphisms.
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Richard Feynman
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Notes
- 1.
Think of 3V as {0,1,2}-vectors of length |V|.
- 2.
It is easy to show that an equivalent definition of k-submodularity is a generalisation of submodularity and bisubmodularity in terms of two k-tuples of pairwise disjoint subsets of a given finite set.
- 3.
A chain is a binary tree in which all nodes except leaves have exactly one child.
- 4.
A fork is a binary tree in which all nodes except leaves and one special node have exactly one child. The special node has exactly two children.
- 5.
A ternary operation f:D 3→D is called Mal’tsev if f(x,y,y)=f(y,y,x)=x for all x,y∈D.
References
Barto, L., Kozik, M.: Constraint satisfaction problems of bounded width. In: Proceedings of the 50th Annual IEEE Symposium on Foundations of Computer Science (FOCS’09), pp. 461–471. IEEE Computer Society, Los Alamitos (2009)
Bilbao, J.M., Fernández, J.R., Jiménez, N., López, J.J.: Survey of bicooperative games. In: Chinchuluun, A., Pardalos, P.M., Migdalas, A., Pitsoulis, L. (eds.) Pareto Optimality, Game Theory and Equilibria. Springer, Berlin (2008)
Bouchet, A.: Greedy algorithm and symmetric matroids. Math. Program. 38(1), 147–159 (1987)
Bulatov, A.: A dichotomy theorem for constraint satisfaction problems on a 3-element set. J. ACM 53(1), 66–120 (2006)
Bulatov, A., Dalmau, V.: A simple algorithm for Mal’tsev constraints. SIAM J. Sci. Comput. 36(1), 16–27 (2006)
Chandrasekaran, R., Kabadi, S.N.: Pseudomatroids. Discrete Math. 71(3), 205–217 (1988)
Cohen, D., Jeavons, P.: The complexity of constraint languages. In: Rossi, F., van Beek, P., Walsh, T. (eds.) The Handbook of Constraint Programming. Elsevier, Amsterdam (2006)
Cohen, D.A., Cooper, M.C., Jeavons, P.G.: Generalising submodularity and Horn clauses: tractable optimization problems defined by tournament pair multimorphisms. Theor. Comput. Sci. 401(1–3), 36–51 (2008)
Cohen, D.A., Cooper, M.C., Jeavons, P.G., Krokhin, A.A.: The complexity of soft constraint satisfaction. Artif. Intell. 170(11), 983–1016 (2006)
Cooper, M.C.: Minimization of locally defined submodular functions by optimal soft arc consistency. Constraints 13(4), 437–458 (2008)
Cooper, M.C., de Givry, S., Sánchez, M., Schiex, T., Zytnicki, M., Werner, T.: Soft arc consistency revisited. Artif. Intell. 174(7–8), 449–478 (2010)
Creed, P., Živný, S.: On minimal weighted clones. In: Proceedings of the 17th International Conference on Principles and Practice of Constraint Programming (CP’11). Lecture Notes in Computer Science, vol. 6876, pp. 210–224. Springer, Berlin (2011)
Dalmau, V.: Generalized majority-minority operations are tractable. Log. Methods Comput. Sci. 2(4) (2006)
Fujishige, S., Iwata, S.: Bisubmodular function minimization. SIAM J. Discrete Math. 19(4), 1065–1073 (2005)
Huber, A., Kolmogorov, V.: Towards minimizing k-submodular functions. In: Proceedings of the 2nd International Symposium on Combinatorial Optimization (ISCO’12) (2012)
Huber, A., Krokhin, A., Powell, R.: Skew bisubmodularity and valued CSPs. In: Proceedings of the 24th ACM-SIAM Symposium on Discrete Algorithms (SODA’13). SIAM, Philadelphia (2012)
Idziak, P.M., Markovic, P., McKenzie, R., Valeriote, M., Willard, R.: Tractability and learnability arising from algebras with few subpowers. SIAM J. Comput. 39(7), 3023–3037 (2010)
Iwata, S., Fleischer, L., Fujishige, S.: A combinatorial strongly polynomial algorithm for minimizing submodular functions. J. ACM 48(4), 761–777 (2001)
Jeavons, P., Cohen, D., Cooper, M.C.: Constraints, consistency and closure. Artif. Intell. 101(1–2), 251–265 (1998)
Jeavons, P.G., Cohen, D.A., Gyssens, M.: Closure properties of constraints. J. ACM 44(4), 527–548 (1997)
Jeavons, P.G., Cooper, M.C.: Tractable constraints on ordered domains. Artif. Intell. 79(2), 327–339 (1995)
Jeavons, P.G., Živný, S.: Tractable valued constraints. In: Bordeaux, L., Hamadi, Y., Kohli, P., Mateescu, R. (eds.) Tractability: Practical Approaches to Hard Problems. Cambridge University Press, Cambridge (2012, to appear)
Jonsson, P., Kuivinen, F., Thapper, J.: Min CSP on four elements: moving beyond submodularity. In: Proceedings of the 17th International Conference on Principles and Practice of Constraint Programming (CP’11). Lecture Notes in Computer Science, vol. 6876, pp. 438–453. Springer, Berlin (2011)
Khot, S.: On the unique games conjecture. In: Proceedings of the 25th Annual IEEE Conference on Computational Complexity (CCC’10), pp. 99–121. IEEE Computer Society, Los Alamitos (2010). Invited survey
Kolmogorov, V.: Submodularity on a tree: unifying l ♯-convex and bisubmodular functions. In: Proceedings of the 36th International Symposium on Mathematical Foundations of Computer Science (MFCS’11). Lecture Notes in Computer Science, vol. 6907, pp. 400–411. Springer, Berlin (2011)
Kolmogorov, V.: Minimizing a sum of submodular functions. Discrete Appl. Math. 160(15), 2246–2258 (2012)
Kolmogorov, V., Živný, S.: The complexity of conservative valued CSPs. In: Proceedings of the 23rd Annual ACM-SIAM Symposium on Discrete Algorithms (SODA’12), pp. 750–759. SIAM, Philadelphia (2012). Full version available on arXiv:1110.2809
Krokhin, A., Larose, B.: Maximizing supermodular functions on product lattices, with application to maximum constraint satisfaction. SIAM J. Discrete Math. 22(1), 312–328 (2008)
Kuivinen, F.: On the complexity of submodular function minimisation on diamonds. Discrete Optim. 8(3), 459–477 (2011)
McCormick, S.T., Fujishige, S.: Strongly polynomial and fully combinatorial algorithms for bisubmodular function minimization. Math. Program. 122(1), 87–120 (2010)
Qi, L.: Directed submodularity, ditroids and directed submodular flows. Math. Program. 42(1–3), 579–599 (1988)
Raghavendra, P.: Approximating NP-hard problems: efficient algorithms and their limits. Ph.D. thesis, University of Washington (2009)
Rossi, F., van Beek, P., Walsh, T. (eds.): The Handbook of Constraint Programming. Elsevier, Amsterdam (2006)
Schrijver, A.: A combinatorial algorithm minimizing submodular functions in strongly polynomial time. J. Comb. Theory, Ser. B 80(2), 346–355 (2000)
Thapper, J., Živný, S.: The power of linear programming for valued CSPs. In: Proceedings of the 53rd Annual IEEE Symposium on Foundations of Computer Science (FOCS’12). IEEE, New York (2012). Preliminary version available on arXiv:1204.1079
Živný, S.: The complexity and expressive power of valued constraints. Ph.D. thesis, University of Oxford (2009)
Živný, S., Cohen, D.A., Jeavons, P.G.: The expressive power of binary submodular functions. Discrete Appl. Math. 157(15), 3347–3358 (2009)
Živný, S., Jeavons, P.G.: Classes of submodular constraints expressible by graph cuts. Constraints 15(3), 430–452 (2010)
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Živný, S. (2012). Tractable Languages. In: The Complexity of Valued Constraint Satisfaction Problems. Cognitive Technologies. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-33974-5_6
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