Fixed-parameter tractability of error correction in graphical linear systems
Paper i proceeding, 2013

In an overdetermined and feasible system of linear equations Ax=b, let vector b be corrupted, in the way that at most k entries are off their true values. Assume that we can check in the restricted system given by any minimal dependent set of rows, the correctness of all corresponding values in b. Furthermore, A has only coefficients 0 and 1, with at most two 1s in each row. We wish to recover the correct values in b and x as much as possible. The problem arises in a certain chemical mixture inference application in molecular biology, where every observable reaction product stems from at most two candidate substances. After formalization we prove that the problem is NP-hard but fixed-parameter tractable in k. The FPT result relies on the small girth of certain graphs.


sparse system of linear equations

parameterized algorithm

even cycle matroid

error correction


Peter Damaschke

Chalmers, Data- och informationsteknik, Datavetenskap

Ömer Egecioglu

Leonid Molokov

Chalmers, Data- och informationsteknik, Datavetenskap

7th International Workshop on Algorithms and Computation WALCOM 2013, Lecture Notes in Computer Science

Vol. 7748 245-256


Grundläggande vetenskaper


Bioinformatik (beräkningsbiologi)

Datavetenskap (datalogi)

Diskret matematik


Livsvetenskaper och teknik