Title
Experimenting an approximation algorithm for the LCS
Abstract
The problem of finding the longest common subsequence (lcs) of a given set of sequences over an alphabet Σ occurs in many interesting contexts, such as data compression and molecular biology, in order to measure the “similarity degree” among biological sequences. Since the problem is NP-complete in its decision version (i.e. does there exist a lcs of length at least k , for a given k ?) even over fixed alphabet, polynomial algorithms which give approximate solutions have been proposed. Among them, Long Run (LR) is the only one with guaranteed constant performance ratio. In this paper, we give a new approximation algorithm for the longest common subsequence problem: the Expansion Algorithm (EA). First of all, we prove that the solution found by the Expansion Algorithm is always at least as good as the one found by LR. Then we report the results of an experimentation with two different groups of instances, which show that EA clearly outperforms Long Run in practice.
Year
DOI
Venue
2001
10.1016/S0166-218X(00)00300-0
Discrete Applied Mathematics
Keywords
Field
DocType
approximation algorithm,longest common subsequence,molecular biology,data compression
Approximation algorithm,Dynamic programming,Discrete mathematics,Combinatorics,Longest increasing subsequence,Longest common subsequence problem,Hunt–McIlroy algorithm,Combinatorial optimization,Greedy algorithm,Data compression,Mathematics
Journal
Volume
Issue
ISSN
110
1
Discrete Applied Mathematics
Citations 
PageRank 
References 
17
0.98
13
Authors
3
Name
Order
Citations
PageRank
Paola Bonizzoni11078.86
Gianluca Della Vedova234236.39
Giancarlo Mauri32106297.38