Title
An O(n^3)-Time Algorithm for Tree Edit Distance
Abstract
The edit distance between two ordered trees with vertex labels is the min- imum cost of transforming one tree into the other by a sequence of elementary op- erations consisting of deleting and relabel- ing existing nodes, as well as inserting new nodes. In this paper, we present a worst- case O(n3)-time algorithm for this problem, improving the previous best O(n3 log n)- time algorithm (6). Our result requires a novel adaptive strategy for deciding how a dynamic program divides into subproblems (which is interesting in its own right), to- gether with a deeper understanding of the previous algorithms for the problem. We also prove the optimality of our algorithm among the family of decomposition strategy algorithms—which also includes the previ- ous fastest algorithms—by tightening the known lower bound of (n2 log2 n) (4) to (n3), matching our algorithm's running time. Furthermore, we obtain matching up- per and lower bounds of �(nm2(1+log n m)) when the two trees have different sizes m and n, where m < n.
Year
DOI
Venue
2006
10.1145/1644015.1644017
Clinical Orthopaedics and Related Research
Keywords
DocType
Volume
data structure,edit distance,lower bound
Journal
abs/cs/060
Issue
ISSN
Citations 
1
ACM Transactions on Algorithms 6(1): (2009)
15
PageRank 
References 
Authors
0.66
6
4
Name
Order
Citations
PageRank
Erik D. Demaine14624388.59
Shay Mozes229222.87
Benjamin Rossman329820.00
Oren Weimann454537.11