ChaoBunge {SPECIES} | R Documentation |
Coverage-duplication estimator for species richness
Description
This function calculates coverage-duplication based estimator from a Poisson-Gamma model by Chao and Bunge 2002.
Usage
ChaoBunge(n, t = 10,conf = 0.95)
Arguments
n |
a matrix or a numerical data frame of two columns. It is also called the “frequency of frequencies” data in literature. The first column is the frequency |
t |
a positive integer. |
conf |
a positive number |
Value
The function ChaoBunge
returns a list of: Nhat
, SE
and CI
.
Nhat |
point estimate. |
SE |
standard error(s) of the point estimate. |
CI |
confidence interval using a log transformation explained in Chao 1987. |
Author(s)
Ji-Ping Wang, Department of Statistics, Northwestern University
References
Chao, A. (1984), Nonparametric Estimation of the Number of Classes in a Population, Scandinavian Journal of Statistics, 11, 265-270.
Chao, A., and Bunge, J. (2002), Estimating the Number of Species in a Stochastic Abundance Model, Biometrics, 58, 531-539.
Examples
library(SPECIES)
##load data from the package,
##"butterfly" is the famous butterfly data by Fisher 1943.
data(butterfly)
##output estimates from all 4 methods using cutoff t=10
ChaoBunge(butterfly,t=10)