Abstract
We analyze the distribution of the running time of Mulmuley's randomized algorithm for computing the intersections of n given segments in the plane. Its expectation has been known to be O(n log n+k), where k is the number of intersections. We show that for values of k not too close to n (k≥Cn log 15 n for a large enough constant C), the running time is sharply concentrated around the expected value; e.g., the probability that the expected value is exceeded more than twice is O(n − c), where c can be an arbitrarily large constant (its choice determines the value of C needed in the assumption). Our proof uses an isoperimetric inequality for permutations.
This research by the first author has been supported by International Computer Science Institute at Berkeley, CA, USA. Research by the second author was supported by NSF Presidential Young Investigator Award CCR-9058440.
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
H. Alt, L. J. Guibas, K. Mehlhorn, R. M. Karp, and A. Wigderson. A Method for Obtaining Randomized Algorithms with Small Tail Probabilities. Algorithmica, submitted.
B. Aronov, H. Edelsbrunner, L.J. Guibas, and M. Sharir. The number of edges of many faces in a line segment arrangement. Tech. Report 90-46, DIMACS Center, Piscataway, NJ, 1990. Combinatorica, to appear.
J. L. Bentley and T. A. Ottmann. Algorithms for reporting and counting geometric intersections. IEEE Transactions on Computers, 28:643–647, 1979.
B. Bollobás. Martingales, isoperimetric inequalities and random graphs, pages 113–139. Math. Soc. J. Bolyai, 1987.
B. Chazelle and H. Edelsbrunner. An optimal algorithm for intersecting line segments in the plane. In Proc. 29. IEEE Symposium on Theory of Computer Science, pages 590–600, 1988.
B. Chazelle, L. Guibas, and D. T. Lee. The power of geometric duality. BIT, 25(1), 1985.
B. Chazelle. Reporting and counting segment intersections. Journal of Computer and System Sciences, 32:156–182, 1986.
K. L. Clarkson and P. Shor. New applications of random sampling in computational geometry II. Discrete & Computational Geometry, 4, 1989.
H. Edelsbrunner. Algorithms in combinatorial geometry. Springer, 1987.
H. Edelsbrunner, L. Guibas, and M. Sharir. The complexity and construction of many faces in arrangements of lines and segments. Discrete & Computational Geometry, 5:161–196, 1990.
H. Edelsbrunner, J. O'Rourke, and R. Seidel. Constructing arrangements of hyperplanes with applications. SIAM Journal on Computing, 15:341–363, 1986.
T. Hagerup. An application of martingales to computational geometry. Lecture at Computational geometry workshop, Dagstuhl, FRG, October 1990.
T. Hagerup and C. Rüb. A Guided Tour of Chernoff Bounds. Inform. Proc. Letters 33 (1989/90), pp 305–308.
K. Mehlhorn, M. Sharir, and E. Welzl. Tail estimates for the space complexity of randomized incremental algorithms. To appear in Proc. 3rd ACM-SIAM Symp. on Discrete Algorithms, 1992.
V. D. Milman and G. Schechtman. Asymptotic theory of finite dimensional normed spaces. LNM 1200, Springer-Verlag, 1986.
K. Mulmuley. A fast planar partition algorithm: Part I. In Proc. 29. IEEE Symposium on Theory of Computer Science, pages 33–43, 1988.
R. Seidel. Backwards analysis of randomized geometric algorithms. International Computer Science Institute (ICSI) Berkeley, Report TR-92-014. Also to appear in New Trends in Discrete and Computational Geometry, J. Pach (ed.), Springer Verlag.
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 1992 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Matoušek, J., Seidel, R. (1992). A tail estimate for Mulmuley's segment intersection algorithm. In: Kuich, W. (eds) Automata, Languages and Programming. ICALP 1992. Lecture Notes in Computer Science, vol 623. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-55719-9_94
Download citation
DOI: https://doi.org/10.1007/3-540-55719-9_94
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-55719-7
Online ISBN: 978-3-540-47278-0
eBook Packages: Springer Book Archive