Negative Examples for Sequential Importance Sampling of Binary Contingency Tables
نویسندگان
چکیده
منابع مشابه
Efficient Importance Sampling for Binary Contingency Tables
Importance sampling has been reported to produce algorithms with excellent empirical performance in counting problems. However, the theoretical support for its efficiency in these applications has been very limited. In this paper, we propose a methodology that can be used to design efficient importance sampling algorithms for counting and test their efficiency rigorously. We apply our technique...
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We describe an algorithm for the sequential sampling of entries in multiway contingency tables with given constraints. The algorithm can be used for computations in exact conditional inference. To justify the algorithm, a theory relates sampling values at each step to properties of the associated toric ideal using computational commutative algebra. In particular, the property of interval cell c...
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Given positive integers r1; r2; : : : rm and c1; c2; : : : cn, let I(r; c) be the set ofm n arrays with nonnegative integer entries and row sums r1; r2; : : : rm respectively and column sums c1; c2; : : : cn respectively. Elements of I(r; c) are called contingency tables with these row and column sums. We consider two related problems on contingency tables. Given r1; r2; : : : rm and c1; c2; : ...
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We study the problem of sampling contingency tables (nonnegative integer matrices with specified row and column sums) uniformly at random. We give an algorithm which runs in polynomial time provided that the row sums ri and the column sums cj satisfy ri (n 3/ m log m), and cj (m 3/ n log n). This algorithm is based on a reduction to continuous sampling from a convex set. The same approach was t...
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ژورنال
عنوان ژورنال: Algorithmica
سال: 2011
ISSN: 0178-4617,1432-0541
DOI: 10.1007/s00453-011-9569-3