bray.curtis: Similarity/Dissimilarity Indices

In fossil: Palaeoecological and Palaeogeographical Analysis Tools

Description

Functions to calculate the ecological distance between two groups

Usage

braun.blanquet(x, y)
bray.curtis(x, y)
euclidean(x,y)
kulczynski(x,y)
jaccard(x, y)
manhattan(x, y)
morisita.horn(x, y)
ochiai(x, y)
simpson(x, y)
sorenson(x, y)

Arguments

x	species from group A
y	species from group B

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. For details on each index, please consult the references.

Value

Returns the similarity index for the two sites in question.

Author(s)

Matthew Vavrek

References

Shi, G. R. 1993. Multivariate data analysis in palaeoecology and palaeobiogeography – a review. Palaeogeography, Palaeoclimatology, Palaeoecology 105: 199–234.

Magurran, A. E. 2004. Measuring Biological Diversity. Oxford, Blackwell.

See Also

dino.dist

Examples

##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)

Example output

Loading required package: sp
Loading required package: maps
Loading required package: shapefiles
Loading required package: foreign

Attaching package: 'shapefiles'

The following objects are masked from 'package:foreign':

    read.dbf, write.dbf

[1] 0.6060606
[1] 0.4285714
[1] 0.6
[1] 0.6
[1] 0.7806971

fossil documentation built on March 23, 2020, 5:06 p.m.