preseqR.interpolate.mincount {preseqR}R Documentation

Interpolating the number of species represented r or more times

Description

Interpolating the expected number of species represented at least r times in a random sample based on an initial sample.

Usage

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

Arguments

ss

An positive double equal to the step size between samples.

n

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

r

A positive integer.

Details

Assume that a random sample (subsample) follows a multivariant hypergeometric distribution given an initial sample. The expected number of unique species represented at least r times in the subsample is then calculated by an expended version of the formula in Heck Jr, KL. et al. (1975).

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.

Author(s)

Chao Deng

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

## load library
library(preseqR)

## import data
data(ShakespeareWordHist)

## The expected number of species represented twice or more in a random sample 
## The step size is 1e5; the initial sample is "ShakespeareWordHist"
preseqR.interpolate.mincount(n=ShakespeareWordHist, ss=1e5, r=2)

[Package preseqR version 3.1.2 Index]