Computing Reviews
Today's Issue Hot Topics Search Browse Recommended My Account Log In
Review Help
Search
Computing the expected value and variance of geometric measures
Tsirogiannis C., Staals F., Pellissier V. Journal of Experimental Algorithmics23 (2):1-32,2018.Type:Article
Date Reviewed: Nov 9 2018

Do species that inhabit a certain area form an ecosystem or are they a random collection? To answer this question, ecologists select appropriate numerical characteristics: average body mass, body length, and so on. Each species is described by a point in the corresponding d-dimensional space and all observed species form a set of points. We can then describe species diversity by computing a geometric measure of this set: the volume of the smallest bounding box or of the convex hull, the diameter of the smallest enclosing sphere, the mean pairwise distance between the points, and so on.

The computed value of the selected measure is then compared with the mean value of this measure over all possible random selections of points from the set of all species, taking into account the corresponding standard deviation. If at a given geographic location the value of the measure differs from the mean by more than two (or three) standard deviations, then we are reasonably confident that we have an ecosystem and not a random collection of species. The corresponding mean and standard deviation values are usually computed by Monte Carlo simulations.

The main limitation of this approach is that it takes too much computation time. The authors propose much more efficient algorithms for computing the mean and standard deviation. Even faster algorithms become possible if we take into account that for ecological purposes, it is sufficient to compute the mean and standard deviation with some accuracy.

Reviewer:  V. Kreinovich Review #: CR146314 (1902-0061)
Bookmark and Share
  Featured Reviewer  
 
Biology And Genetics (J.3 ... )
 
 
Algorithm Design And Analysis (G.4 ... )
 
 
Computational Geometry And Object Modeling (I.3.5 )
 
 
Life And Medical Sciences (J.3 )
 
Would you recommend this review?
yes
no
Other reviews under "Biology And Genetics": Date
Discovering the secrets of DNA
Friedland P., Kedes L. Communications of the ACM 28(11): 1164-1186, 1985. Type: Article
May 1 1986
The formation of three-dimensional biological structures: computer uses and future needs
Levinthal C.  Computer culture: the scientific, intellectual, and social impact of the computer (, New York,1801984. Type: Proceedings
Sep 1 1986
Computer techniques in neuroanatomy
Capowski J., Plenum Press, New York, NY, 1989. Type: Book (9789780306432637)
Nov 1 1990
more...

E-Mail This Printer-Friendly
Send Your Comments
Contact Us
Reproduction in whole or in part without permission is prohibited.   Copyright 1999-2024 ThinkLoud®
Terms of Use
| Privacy Policy