Title
Approximate Satisfiability and Equivalence
Abstract
Inspired by Property Testing, we relax the classical satisfiability U |= F between a finite structure U of a class K and a formula F, to a notion of \varessilon-satisfiability U |=\varepsilon F, and the classical equivalence F_1 \equiv F_2 between two formulas F_1 and F_2, to \varepsilon-equivalence F1 \equiv_\varepsilon F2 for \varepsilon 0. We consider the class of strings and trees with the edit distance with moves, and show that these approximate notions can be efficiently decided. We use a statistical embedding of words (resp. trees) into l_1, which generalizes the original Parikh mapping, obtained by sampling O(f(\epsilon)) finite samples of the words (resp. trees). We give a tester for equality and membership in any regular language, in time independent of the size of the structure. Using our geometrical embedding, we can also test the equivalence between two regular properties on words, defined by Monadic Second Order formulas. Our equivalence tester has polynomial time complexity in the size of the automaton (or regular expression), for a fixed varepisolon, whereas the exact version of the equivalence problem is PSPACE-complete. Last, we extend the geometric embedding, and hence the tester algorithms, to infinite regular languages and to context-free languages. For context-free languages, the equivalence tester has an exponential time complexity, whereas the exact version is undecidable.% MathType!MTEF!2!1!+- % feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyyyIOlaaa!37B6! \[\equiv\]
Year
DOI
Venue
2010
10.1137/070703776
SIAM J. Comput.
Keywords
Field
DocType
regular property,polynomial time complexity,classical equivalence,equivalence problem,equivalence tester,approximate satisfiability,worse time complexity,exact version,exponential time complexity,regular expression,regular language,approximation,automata,satisfiability
Discrete mathematics,Combinatorics,Context-free language,Property testing,Embedding,Satisfiability,Decidability,Equivalence (measure theory),Regular language,Time complexity,Mathematics
Journal
Volume
Issue
ISSN
39
6
0097-5397
ISBN
Citations 
PageRank 
0-7695-2631-4
14
0.68
References 
Authors
22
3
Name
Order
Citations
PageRank
eldar fischer181563.82
Frédéric Magniez257044.33
Michel De Rougemont3138143.69