Related Experiment Video
Updated: Jun 27, 2026
09:33
Scalable, Flexible, and Cost-Effective Seedling Grafting
Published on: January 6, 2023
A practical method for exact computation of subtree prune and regraft distance
1Department of Computer Science and Engineering, University of Connecticut, Storrs, CT 06269, USA. ywu@engr.uconn.edu
Bioinformatics (Oxford, England)
|November 21, 2008
Summary
This study introduces a new computational method using integer linear programming to calculate the exact rooted subtree prune and regraft ((r)SPR) distance. This approach offers improved accuracy and efficiency for large biological trees compared to existing tools.
Area of Science:
- Computational Biology
- Bioinformatics
- Phylogenetics
Background:
- Subtree prune and regraft (SPR) operations are fundamental for analyzing evolutionary relationships represented by rooted binary trees.
- The rooted SPR ((r)SPR) distance quantifies the minimum operations to transform one tree into another, a key metric in phylogenetic analysis.
- Existing computational tools struggle with calculating (r)SPR distance for large trees or those with significant distances.
Purpose of the Study:
- To develop a practical and accurate method for computing the exact (r)SPR distance.
- To address the limitations of current software in handling large-scale phylogenetic tree comparisons.
Main Methods:
- Integer linear programming (ILP) was employed to formulate and solve the (r)SPR distance computation problem.
- The proposed ILP method was validated on both simulated and real biological datasets.
Main Results:
- The new ILP-based method demonstrates superior accuracy and efficiency over existing software tools.
- The approach successfully computes the exact (r)SPR distance for numerous large trees with substantial (r)SPR distances.
- Experimental results confirm the practical applicability and performance gains of the new method.
Conclusions:
- Integer linear programming provides an effective solution for calculating the exact (r)SPR distance.
- This method enhances the capability to analyze complex evolutionary histories represented by large phylogenetic trees.
- The developed tool offers a significant advancement for computational biology research requiring precise tree comparison.
Related Concept Videos
01:19Survival Tree
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a survival tree begins...
Building a Survival Tree
Constructing a survival tree begins...
01:29Distance Problem
When an object's velocity changes over time, the total distance traveled can be determined by summing small displacement intervals over short increments. This approach approximates the true distance through numerical summation and the use of integral calculus. An estimate of the total displacement can be obtained by measuring velocity at regular intervals and multiplying each value by the corresponding time step.If a runner accelerates over the first three seconds of a race, speed measurements...
01:20The Distance Formula
In geometry, measuring the direct distance between two points on a plane is essential in various practical and theoretical applications. Whether in navigation, engineering, or computer graphics, determining the shortest path between two locations involves using the distance formula. This formula is derived from the Pythagorean Theorem, which relates the lengths of the sides of a right triangle. On a coordinate plane, the horizontal and vertical distances between two points serve as the legs of...
01:24Area Computation by the Alternative Coordinate Method
The alternative coordinate method, also known as the Shoelace Formula, is a technique for determining the area of a traverse using Cartesian coordinates. This method relies on the sequential arrangement of x and y coordinates for each point of the shape, ensuring accuracy and ease of application.In this approach, each corner's x and y coordinates are listed as fractions, with the x-coordinate as the numerator and the y-coordinate as the denominator. These coordinates are arranged sequentially...
01:15Construction of Root Locus
The construction of a root locus involves several key steps to analyze and visualize the behavior of a system's poles with varying gain. The number of branches in the root locus equals the number of closed-loop poles and is symmetrical about the real axis.
For positive gain values, the root locus exists on the real axis to the left of an odd number of finite open-loop poles or zeros. The root locus starts at the open-loop poles and traces the paths of the closed-loop poles as the gain increases.
For positive gain values, the root locus exists on the real axis to the left of an odd number of finite open-loop poles or zeros. The root locus starts at the open-loop poles and traces the paths of the closed-loop poles as the gain increases.
01:02Quantifying and Rejecting Outliers: The Grubbs Test
Sometimes, a data set can have a recorded numerical observation that greatly deviates from the rest of the data. Assuming that the data is normally distributed, a statistical method called the Grubbs test can be used to determine whether the observation is truly an outlier. To perform a two-tailed Grubbs test, first, calculate the absolute difference between the outlier and the mean. Then, calculate the ratio between this difference and the standard deviation of the sample. This number is...