, Volume 15, Issue 1, pp 67–83

An analysis of a Monte Carlo algorithm for estimating the permanent

  • Alan Frieze
  • Mark Jerrum

DOI: 10.1007/BF01294460

Cite this article as:
Frieze, A. & Jerrum, M. Combinatorica (1995) 15: 67. doi:10.1007/BF01294460


Karmarkar, Karp, Lipton, Lovász, and Luby proposed a Monte Carlo algorithm for approximating the permanent of a non-negativen×n matrix, which is based on an easily computed, unbiased estimator. It is not difficult to construct 0,1-matrices for which the variance of this estimator is very large, so that an exponential number of trials is necessary to obtain a reliable approximation that is within a constant factor of the correct value.

Nevertheless, the same authors conjectured that for a random 0,1-matrix the variance of the estimator is typically small. The conjecture is shown to be true; indeed, for almost every 0,1-matrixA, just O(nw(n)e-2) trials suffice to obtain a reliable approximation to the permanent ofA within a factor 1±ɛ of the correct value. Here ω(n) is any function tending to infinity asn→∞. This result extends to random 0,1-matrices with density at leastn−1/2ω(n).

It is also shown that polynomially many trials suffice to approximate the permanent of any dense 0,1-matrix, i.e., one in which every row- and column-sum is at least (1/2+α)n, for some constant α>0. The degree of the polynomial bounding the number of trials is a function of α, and increases as α→0.

Mathematics Subject Classification (1991)

68 Q 25

Copyright information

© Akadémiai Kiadó 1995

Authors and Affiliations

  • Alan Frieze
    • 1
  • Mark Jerrum
    • 2
  1. 1.Department of MathematicsCarnegie Mellon UniversityPittsburghU.S.A.
  2. 2.Department of Computer ScienceUniversity of EdinburghEdinburghUK