Automatic Generation of Optimal Reductions of Distributions

TL;DR

This paper presents an automated method for generating optimal reductions of distributions to simplify decomposability verification, using incremental algorithms, backtracking, and proof techniques.

Contribution

It introduces an incremental algorithm and validation procedure for automatically producing and verifying minimal distribution reductions.

Findings

Proposed an incremental algorithm for candidate reduction generation.

Developed a reduction validation technique using substitution-based proofs.

Supported recursive generation of small reductions.

Abstract

A reduction of a source distribution is a collection of smaller sized distributions that are collectively equivalent to the source distribution with respect to the property of decomposability. That is, an arbitrary language is decomposable with respect to the source distribution if and only if it is decomposable with respect to each smaller sized distribution (in the reduction). The notion of reduction of distributions has previously been proposed to improve the complexity of decomposability verification. In this work, we address the problem of generating (optimal) reductions of distributions automatically. A (partial) solution to this problem is provided, which consists of 1) an incremental algorithm for the production of candidate reductions and 2) a reduction validation procedure. In the incremental production stage, backtracking is applied whenever a candidate reduction that cannot be validated is produced. A strengthened substitution-based proof technique is used for reduction validation, while a fixed template of candidate counter examples is used for reduction refutation; put together, they constitute our (partial) solution to the reduction verification problem. In addition, we show that a recursive approach for the generation of (small) reductions is easily supported.