theoretical-computer-science / Approximate counting and sampling (FPRAS, Markov chains)

Polynomial-time approximate counting and uniform sampling of contingency tables with arbitrary margins

FPRAS manuscript: one randomized algorithm counts nonnegative integer matrices with prescribed row sums, column sums and entry bounds bijb_{ij} (zeros allowed) within relative error ε\varepsilon with probability 1−δ1-\delta, using unbiased bits and a polynomial bound in the input length, ε−1\varepsilon^{-1} and log⁡δ−1\log\delta^{-1} on every execution. Sampling manuscript: for ordinary tables, an almost-uniform sampler (TV error 2−k2^{-k}) in worst-case polynomial bit time and an exactly uniform sampler in expected polynomial bit time in m,n,log⁡(N+1)m,n,\log(N+1). Exponents are deliberately large; the results are complexity classifications, not practical algorithms, and the exact sampler is polynomial only in expectation.

42Significance / 100
1Frontier events
0Verification tasks
0Recorded attempts

Temporal state

Current frontier

No reconciled state yet.

Append-only history

Frontier timeline

theoretical-computer-scienceSep 24, 2026Significance 42/100Registry: lean checked

Polynomial-time approximate counting and uniform sampling of contingency tables with arbitrary margins

Prior state unknown→proved

FPRAS manuscript: one randomized algorithm counts nonnegative integer matrices with prescribed row sums, column sums and entry bounds bijb_{ij} (zeros allowed) within relative error ε\varepsilon with probability 1−δ1-\delta, using unbiased bits and a polynomial bound in the input length, ε−1\varepsilon^{-1} and log⁡δ−1\log\delta^{-1} on every execution. Sampling manuscript: for ordinary tables, an almost-uniform sampler (T…

SourceReplayReproducedFormal proofStatement auditExternal checkExpert reviewPeer review

Research memory

Claims and attempts

Scoped claims

Source authenticated

FPRAS manuscript: one randomized algorithm counts nonnegative integer matrices with prescribed row sums, column sums and entry bounds bijb_{ij} (zeros allowed) within relative error ε\varepsilon with probability 1−δ1-\delta, using unbiased bits and a polynomial bound in the input length, ε−1\varepsilon^{-1} and log⁡δ−1\log\delta^{-1} on every execution. Sampling manuscript: for ordinary tables, an almost-uniform sampler (TV error 2−k2^{-k}) in worst-case polynomial bit time and an exactly uniform sampler in expected polynomial bit time in m,n,log⁡(N+1)m,n,\log(N+1). Exponents are deliberately large; the results are complexity classifications, not practical algorithms, and the exact sampler is polynomial only in expectation.

FPRAS manuscript: one randomized algorithm counts nonnegative integer matrices with prescribed row sums, column sums and entry bounds bijb_{ij} (zeros allowed) within relative error ε\varepsilon with probability 1−δ1-\delta, using unbiased bits and a polynomial bound in the input length, ε−1\varepsilon^{-1} and log⁡δ−1\log\delta^{-1} on every execution. Sampling manuscript: for ordinary tables, an almost-uniform sampler (TV error 2−k2^{-k}) in worst-case polynomial bit time and an exactly uniform sampler in expected polynomial bit time in m,n,log⁡(N+1)m,n,\log(N+1). Exponents are deliberately large; the results are complexity classifications, not practical algorithms, and the exact sampler is polynomial only in expectation.

Recorded attempts

Evidence graph

Connected research record

Polynomial-time approximate counting and uniform sampling of contingency tables with arbitrary margins — Mathematical Frontier Network