Abstract
Both average-case complexity and the study of the approximability of NP optimisation problems are well established and active fields of research. Many results concerning the average behaviour of approximation algorithms for NP optimisation problems exist, both with respect to their running time and their performance ratio, but a theoretical framework to examine their structural properties with respect to their average-case approximability is not yet established. With this paper, we hope to fill the gap and provide not only the necessary definitions, but show that
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The class of NP optimisation problems with p-computable input distributions has complete problems with respect to an average-approximability preserving reduction.
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The average-time variants of worst-case approximation classes form a strict hierarchy if NP is not easy on average. By linking average-ratio approximation algorithms to p-time algorithms schemes, we can prove similar hierarchy results for the average-ratio versions of the approximation classes. This is done under the premise that not all NP-problems with p-computable input distributions have p-time algorithm schemes.
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The question whether NP is easy on average is equivalent to the question whether every NP optimisation problem with a p-computable input distribution has an average p-time approximation scheme.
Classification: Computational and structural complexity.
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References
Arora, S., Lund, C., Motwani, R., Sudan, M., Szegedy, M.: Proof Verification and Hardness of Approximation Problems. In: 33rd FOCS, IEEE, Los Alamitos (1992)
Ausiello, G., Crescenzi, P., Gambosi, G., Kann, V., Marchetti-Spaccamela, A., Protasi, M.: Complexity and Approximation. Springer, Heidelberg (1999)
Balcázar, J., Díaz, J., Gabarró, J.: Structural Complexity I, 2nd edn. Springer, Heidelberg (1995)
Belanger, J., Wang, J.: On average-P vs. average-NP. In: Ambos-Spies, K., Homer, S., Schöning, U. (eds.) Complexity Theory – Current Research. Cambridge University Press, Cambridge (1993)
Belanger, J., Wang, J.: On the NP-isomorphism with respect to random instances. JCSS 50, 151–164 (1995)
Ben-David, S., Chor, B., Goldreich, O., Luby, M.: On the theory of average case complexity. JCSS 44, 193–219 (1992)
Buhrman, H., Fortnow, L., Pavan, A.: Some results on derandomization. In: Alt, H., Habib, M. (eds.) STACS 2003. LNCS, vol. 2607, pp. 212–222. Springer, Heidelberg (2003)
Coja-Oghlan, A., Taraz, A.: Colouring random graphs in expected polynomial time. In: Alt, H., Habib, M. (eds.) STACS 2003. LNCS, vol. 2607, pp. 487–498. Springer, Heidelberg (2003)
Crescenzi, P., Kann, V., Silvestri, R., Trevisan, L.: Structure in approximation classes. SIAM J. Comp. 28(5), 1759–1782 (1999)
Crescenzi, P., Panconesi, A.: Completeness in approximation classes. Inf. and Comp. 93, 241–262 (1991)
Du, D.-Z., Ko, K.: Theory of Computational Complexity. John Wiley & Sons, Chichester (2000)
Feige, U., Goldwasser, S., Lovász, L., Safra, S., Szegedy, M.: Approximating Clique is almost NP-complete. In: 32nd FOCS. IEEE, Los Alamitos (1991)
Garey, M., Johnson, D.: The complexity of near optimal graph coloring. J. ACM 23, 43–49 (1976)
Grimmet, G., McDiarmid, C.: On colouring random graphs. Math. Proc. Camb. Phil. Soc. 77, 313–324 (1975)
Gurevich, Y.: Complete and incomplete randomized NP problems. In: 28th FOCS. IEEE, Los Alamitos (1987)
Gurevich, Y.: Average case completeness. JCSS 42, 346–398 (1991)
Impagliazzo, R.: A personal view of average-case complexity. In: 10th Structure. IEEE, Los Alamitos (1995)
Köbler, J., Schuler, R.: Average-case intractability vs. worst-case intractability. In: Brim, L., Gruska, J., Zlatuška, J. (eds.) MFCS 1998. LNCS, vol. 1450, p. 493. Springer, Heidelberg (1998)
Krentel, M.: The complexity of optimization problems. JCSS 36, 490–509 (1988)
Kreuter, B., Nierhoff, T.: Greedily approximating the r-independent set and kcenter problems on random instances. In: Rand. and Approx. Techniques in Comp. Science, Springer, Heidelberg (1997)
Levin, L.: Problems, complete in “average” instance. In: 16th STOC. ACM, New York (1984)
McDiarmid, C.: Colouring random graphs. Ann. Operations Res. 1, 183–200 (1984)
Nickelsen, A., Schelm, B.: Average-case computations – Comparing AvgP, HP, and Nearly-P. In: CCC (2005) (to appear)
Papadimitriou, C.: Computational Complexity. Addison Wesley, Reading (1994)
Schapire, R.: The emerging theory of average-case complexity. Technical Report MIT/LCS/TM-431, MIT Laboratory of Computer Science (1990)
Schelm, B.: Average-Case Approximability of Optimisation Problems. Doctoral Thesis, TU Berlin, Fak. f. Elektrotechnik und Informatik (2004), http://edocs.tu-berlin.de/diss/2004/schelmbirgit.pdf
Schindelhauer, C.: Average- und Median-Komplexitätsklassen. Doctoral Thesis, Universität Lübeck (1996)
Schuler, R., Watanabe, O.: Toward average-case complexity analysis of NP optimization problems. In: 10th Structure. IEEE, Los Alamitos (1995)
Wang, J.: Average-case computational complexity theory. In: Hemaspaandra, L., Selman, A. (eds.) Complexity Theory Retrospective II. Springer, Heidelberg (1997)
Wang, J.: Average case intractable NP-problems. In: Du, D.-Z., Ko, K. (eds.) Advances in Complexity and Algorithms. Kluwer, Dordrecht (1997)
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Schelm, B. (2005). Average-Case Non-approximability of Optimisation Problems. In: Liśkiewicz, M., Reischuk, R. (eds) Fundamentals of Computation Theory. FCT 2005. Lecture Notes in Computer Science, vol 3623. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11537311_36
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DOI: https://doi.org/10.1007/11537311_36
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