preseqR (version 4.0.0)

preseqR.interpolate.rSAC: Interpolation

Description

Interpolating the number of species represented at least \(r\) times in a subsample given an initial sample

Usage

preseqR.interpolate.rSAC(n, ss, r=1)

Arguments

n

A two-column matrix. The first column is the frequency \(j = 1,2,\dots\); and the second column is \(N_j\), the number of species with each species represented exactly \(j\) times in the initial sample. The first column must be sorted in an ascending order.

ss

A positive double equal to the step size between subsamples.

r

A positive integer. Default is 1

Value

A two-column matrix for the number of species represented at least \(r\) times in a random sample. The first column is the size of the random sample; the second column is the expected number of species represented at least \(r\) times in the sample.

NULL if failed.

Details

The expected number of species represented at least \(r\) times in the subsample is estimated based on an expended version of the formula by Heck Jr, KL. et al. (1975).

References

Heck Jr, K. L., van Belle, G., & Simberloff, D. (1975). Explicit calculation of the rarefaction diversity measurement and the determination of sufficient sample size. Ecology, 1459-1461.

Examples

# NOT RUN {
## load library
library(preseqR)

## import data
data(Shakespeare)

## The expected number of distinct words represented twice or more in the
## subsample 
preseqR.interpolate.rSAC(n=Shakespeare, ss=1e5, r=2)
# }