Title
A matroid associated with a phylogenetic tree.
Abstract
A (pseudo-) metric D on a finite set X is said to be a 'tree metric' if there is a finite tree with leaf set X and non-negative edge weights so that, for all x, y is an element of X, D (x, y) is the path distance in the tree between x and y. It is well known that not every metric is a tree metric. However, when some such tree exists, one can always find one whose interior edges have strictly positive edge weights and that has no vertices of degree 2, any such tree is - up to canonical isomorphism - uniquely determined by D, and one does not even need all of the distances in order to fully (re-) construct the tree's edge weights in this case. Thus, it seems of some interest to investigate which subsets of (X 2) suffice to determine ('lasso') these edge weights. In this paper, we use the results of a previous paper to discuss the structure of a matroid that can be associated with an (unweighted) X-tree T defined by the requirement that its bases are exactly the 'tight edge-weight lassos' for T, i.e, the minimal subsets of (X 2) that lasso the edge weights of T.
Year
Venue
Keywords
2014
DISCRETE MATHEMATICS AND THEORETICAL COMPUTER SCIENCE
phylogenetic tree,tree metric,matroid,lasso (for a tree),cord (of a lasso)
Field
DocType
Volume
Matroid,Discrete mathematics,Combinatorics,Finite set,Phylogenetic tree,Vertex (geometry),Lasso (statistics),Metric tree,K-ary tree,Isomorphism,Mathematics
Journal
16.0
Issue
ISSN
Citations 
2.0
1462-7264
2
PageRank 
References 
Authors
0.41
1
3
Name
Order
Citations
PageRank
Andreas W. M. Dress141274.54
Katharina T. Huber213924.31
Mike Steel327041.87