TY - GEN
T1 - A Lagrangian relaxation approach for the multiple sequence alignment problem
AU - Althaus, Ernst
AU - Canzar, Stefan
PY - 2007
Y1 - 2007
N2 - We present a branch-and-bound (bb) algorithm for the multiple sequence alignment problem (MSA), one of the most important problems in computational biology. The upper bound at each bb node is based on a Lagrangian relaxation of an integer linear programming formulation for MSA. Dualizing certain inequalities, the Lagrangian sub-problem becomes a pairwise alignment problem, which can be solved efficiently by a dynamic programming approach. Due to a reformulation w.r.t. additionally introduced variables prior to relaxation we improve the convergence rate dramatically while at the same time being able to solve the Lagrangian problem efficiently. Our experiments show that our implementation, although preliminary, outperforms all exact algorithms for the multiple sequence alignment problem.
AB - We present a branch-and-bound (bb) algorithm for the multiple sequence alignment problem (MSA), one of the most important problems in computational biology. The upper bound at each bb node is based on a Lagrangian relaxation of an integer linear programming formulation for MSA. Dualizing certain inequalities, the Lagrangian sub-problem becomes a pairwise alignment problem, which can be solved efficiently by a dynamic programming approach. Due to a reformulation w.r.t. additionally introduced variables prior to relaxation we improve the convergence rate dramatically while at the same time being able to solve the Lagrangian problem efficiently. Our experiments show that our implementation, although preliminary, outperforms all exact algorithms for the multiple sequence alignment problem.
UR - http://www.scopus.com/inward/record.url?scp=38149042024&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=38149042024&partnerID=8YFLogxK
U2 - 10.1007/978-3-540-73556-4_29
DO - 10.1007/978-3-540-73556-4_29
M3 - Conference contribution
AN - SCOPUS:38149042024
SN - 9783540735557
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 267
EP - 278
BT - Combinatorial Optimization and Applications - First International Conference, COCOA 2007, Proceedings
PB - Springer Verlag
T2 - 1st International Conference on Combinatorial Optimization and Applications, COCOA 2007
Y2 - 14 August 2007 through 16 August 2007
ER -