Abstract
The independence number of a graph and its chromatic number are hard to approximate. It is known that, unless coRP = NP, there is no polynomial time algorithm which approximates any of these quantities within a factor of n1-ε for graphs on n vertices.
We show that the situation is significantly better for the average case. For every edge probability p = p(n) in the range n −1/2+ε ≤ p ≤ 3/4, we present an approximation algorithm for the independence number of graphs on n vertices, whose approximation ratio is O((np)1/2/ log n) and whose expected running time over the probability space G(n, p) is polynomial. An algorithm with similar features is described also for the chromatic number.
A key ingredient in the analysis of both algorithms is a new large deviation inequality for eigenvalues of random matrices, obtained through an application of Talagrand’s inequality.
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References
N. Alon, Spectral techniques in graph algorithms, Lecture Notes Comp. Sci. 1380 (C.L. Lucchessi and A. V. Moura, Eds.), Springer, Berlin, 1998, 206–215.
N. Alon and N. Kahale, A spectral technique for coloring random 3-colorable graphs, Proc. 26th ACM STOC, ACM Press (1994), 346–355.
N. Alon, M. Krivelevich and B. Sudakov, Finding a large hidden clique in a random graph, Proc. 9th ACM-SIAM SODA, ACM Press (1998), 594–598.
B. Bollobás, Random graphs, Academic Press, New York, 1985.
B. Bollobás, The chromatic number of random graphs, Combinatorica 8 (1988), 49–55.
R. Boppana, Eigenvalues and graph bisection: An average case analysis, Proc. 28th IEEE FOCS, IEEE (1987), 280–285.
R. Boppana and M. M. Halldórsson, Approximating maximum independent sets by excluding subgraphs, Bit 32 (1992), 180–196.
M. Dyer and A. Frieze, The solution of some random NP-hard problems in polynomial expected time, J. Algorithms 10 (1989), 451–489.
U. Feige and J. Kilian, Zero knowledge and the chromatic number, Proc. 11th IEEE Conf. Comput. Complexity, IEEE (1996), 278–287.
U. Feige and R. Krauthgamer, Finding and certifying a large hidden clique in a semi-random graph, Random Str. Algor. 16 (2000), 195–208.
Z. Füredi and J. Komlós, The eigenvalues of random symmetric matrices, Combinatorica 1 (1981), 233–241.
M. Fürer, C. R. Subramanian and C. E. Veni Madhavan, Coloring random graphs in polynomial expected time, Algorithms and Comput. (Hong Kong 1993), Lecture Notes Comp. Sci. 762, Springer, Berlin, 1993, 31–37.
M. M. Halld orsson, A still better performance guarantee for approximate graph coloring, Inform. Process. Lett. 45 (1993), 19–23.
J. Hästad, Clique is hard to approximate within n1-ε, Proc. 37th IEEE FOCS, IEEE (1996), 627–636.
Approximation algorithms for NP-hard problems, D. Hochbaum, Ed., PWS Publish. Company, Boston, 1997.
R. Karp, Reducibility among combinatorial problems, in: Complexity of computer computations (E. Miller and J. W. Thatcher, eds.) Plenum Press, New York, 1972, 85–103.
L. Kučera, The greedy coloring is a bad probabilistic algorithm, J. Algorithms 12 (1991), 674–684.
L. Lovász, On the Shannon capacity of a graph, IEEE Trans. Inform. Theory 25 (1979), 1–7.
T. Luczak, The chromatic number of random graphs, Combinatorica 11 (1991), 45–54.
H. J. Prömel and A. Steger, Coloring clique-free graphs in polynomial expected time, Random Str. Algor. 3 (1992), 275–402.
M. Saks, Private communication.
M. Talagrand, A new isoperimetric inequality for product measure, and the tails of sums of independent random variables, Geom. Funct. Analysis 1 (1991), 211–223.
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Krivelevich, M., Van Vu, H. (2000). Approximating the Independence Number and the Chromatic Number in Expected Polynomial Time. In: Montanari, U., Rolim, J.D.P., Welzl, E. (eds) Automata, Languages and Programming. ICALP 2000. Lecture Notes in Computer Science, vol 1853. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-45022-X_3
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DOI: https://doi.org/10.1007/3-540-45022-X_3
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