TY - GEN
T1 - Approximating transitive reductions for directed networks
AU - Berman, Piotr
AU - Dasgupta, Bhaskar
AU - Karpinski, Marek
PY - 2009/9/14
Y1 - 2009/9/14
N2 - We consider minimum equivalent digraph problem, its maximum optimization variant and some non-trivial extensions of these two types of problems motivated by biological and social network applications. We provide -approximation algorithms for all the minimization problems and 2-approximation algorithms for all the maximization problems using appropriate primal-dual polytopes. We also show lower bounds on the integrality gap of the polytope to provide some intuition on the final limit of such approaches. Furthermore, we provide APX-hardness result for all those problems even if the length of all simple cycles is bounded by 5.
AB - We consider minimum equivalent digraph problem, its maximum optimization variant and some non-trivial extensions of these two types of problems motivated by biological and social network applications. We provide -approximation algorithms for all the minimization problems and 2-approximation algorithms for all the maximization problems using appropriate primal-dual polytopes. We also show lower bounds on the integrality gap of the polytope to provide some intuition on the final limit of such approaches. Furthermore, we provide APX-hardness result for all those problems even if the length of all simple cycles is bounded by 5.
UR - http://www.scopus.com/inward/record.url?scp=69949150660&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=69949150660&partnerID=8YFLogxK
U2 - 10.1007/978-3-642-03367-4_7
DO - 10.1007/978-3-642-03367-4_7
M3 - Conference contribution
AN - SCOPUS:69949150660
SN - 3642033660
SN - 9783642033667
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 74
EP - 85
BT - Algorithms and Data Structures - 11th International Symposium, WADS 2009, Proceedings
T2 - 11th International Symposium on Algorithms and Data Structures, WADS 2009
Y2 - 21 August 2009 through 23 August 2009
ER -