calc_chao1 {mobr}

Estimation of species richness

Description

calc_chao1 estimates the number of species at the asymptote (S_asymp) of the species accumulation curve based on the methods proposed in Chao (1984, 1987, 2005).

Usage

calc_chao1(x)

Arguments

x

a vector of species abundances or a site-by-species matrix

Details

This function is a trimmed version of iNext::ChaoRichess. T. C. Hsieh, K. H. Ma and Anne Chao are the original authors of the iNEXT package.

Value

a vector of species richness estimates

References

Chao, A. (1984) Nonparametric estimation of the number of classes in a population. Scandinavian Journal of Statistics, 11, 265-270.

Chao, A. (1987) Estimating the population size for capture-recapture data with unequal catchability. Biometrics, 43, 783-791.

Chao, A. (2005) Species estimation and applications. Pages 7907-7916 in N. Balakrishnan, C. B. Read, and B. Vidakovic, editors. Encyclopedia of statistical sciences. Second edition, volume 12. Wiley, New York, New York, USA.

Examples

data(inv_comm)
calc_chao1(inv_comm)