bray.curtis {fossil} | R Documentation |
Functions to calculate the similarities between two groups
bray.curtis(x, y) jaccard(x, y) morisita.horn(x, y) simpson(x, y) sorenson(x, y)
x |
species from group A |
y |
species from group B |
You must provide two separate vectors, with species arranged in the same order, from area A and B. If species are present in one site but not the other, these must be recorded for both sites; the site where they are not found should be coded as a zero. Species not present at either site are ignored. For details on each index, please consult the references.
Returns the similarity index for the two sites in question.
Matthew Vavrek
Magurran, A. E. (2004). Measuring Biological Diversity. Oxford, Blackwell.
##Species counts from two different locations a <- c(1,0,4,3,5,0,0,7) b <- c(2,1,3,0,0,1,0,6) bray.curtis(a,b) jaccard(a,b) simpson(a,b) sorenson(a,b) morisita.horn(a,b)