An improved bound on the maximum agreement subtree problem

نویسندگان

  • Mike A. Steel
  • László A. Székely
چکیده

We improve the lower bound on the extremal version of the Maximum Agreement Subtree problem. Namely we prove that two binary trees on the same n leaves have subtrees with the same ≥ c log log n leaves which are homeomorphic, such that homeomorphism is identity on the leaves.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Solving the Maximum Agreement SubTree and the Maximum Compatible Tree Problems on Many Bounded Degree Trees

Given a set of leaf-labeled trees with identical leaf sets, the well-known Maximum Agreement SubTree problem (MAST) consists of finding a subtree homeomorphically included in all input trees and with the largest number of leaves. Its variant called Maximum Compatible Tree (MCT) is less stringent, as it allows the input trees to be refined. Both problems are of particular interest in computation...

متن کامل

Balanced Randomized Tree Splitting with Applications to Evolutionary Tree Constructions

We present a new technique called balanced randomized tree splitting. It is useful in constructing unknown trees recursively. By applying it we obtain two new results on efficient construction of evolutionary trees: a new upper time-bound on the problem of constructing an evolutionary tree from experiments, and a relatively fast approximation algorithm for the maximum agreement subtree problem ...

متن کامل

Kaikoura Information Processing Letters tree theorems : Computing the maximum agreement subtree

The Maximum Agreement Subtree Problem was posed by Finden and Gordon in 1985, and is as follows: given a set S={s,, sz,..., s,,} and two trees P and Q leaf-labelled by the elements of S, find a maximum cardinality subset S, of S such that PI S, = Q IS,. This problem arises in evolutionary tree construction, where different methods or data yield (possibly) different trees for the same species on...

متن کامل

Approximating the Maximum Isomorphic Agreement Subtree Is Hard

The Maximum Isomorphic Agreement Subtree (MIT) problem is one of the simplest versions of the Maximum Interval Weight Agreement Subtree method (MIWT) which is used to compare phylogenies. More precisely MIT allows to provide a subset of the species such that the exact distances between species in such subset are preserved among all evolutionary trees considered. In this paper, the approximation...

متن کامل

Improved Parametrized Complexity of Maximum Agreement Subtree and Maximum Compatible Tree problems

Given a set of evolutionary trees on a same set of taxa, the maximum agreement subtree problem (MAST), respectively maximum compatible tree problem (MCT), consists of finding a largest subset of taxa such that all input trees restricted to these taxa are isomorphic, respectively compatible. These problems have several applications in phylogenetics such as the computation of a consensus of phylo...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Applied mathematics letters

دوره 22 11  شماره 

صفحات  -

تاریخ انتشار 2009