fossil (version 0.4.0)

chao.sorenson: Chao's Jaccard and Sorenson Estimators of Shared Species

Description

Chao's Jaccard and Sorenson shared species estimators for use with incomplete datasets

Usage

chao.sorenson(x, y)
chao.jaccard(x, y)

Arguments

x

species from group A

y

species from group B

Value

Returns the Chao-Jaccard or Chao-Sorenson similarity index for the two sites in question.

Details

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.

References

Chao, A., R. L. Chazdon, et al. 2005. A new statistical approach for assessing similarity of species composition with incidence and abundance data. Ecology Letters 8: 148-159.

See Also

bray.curtis

Examples

# NOT RUN {
##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)
chao.sorenson(a,b)
chao.jaccard(a,b)

# }