AbdFreqCount {entropart} | R Documentation |

## Abundance Frequency Count of a Community

### Description

Counts the number of species observed the same number of times.

### Usage

```
AbdFreqCount(Ns, Level = NULL, PCorrection="Chao2015", Unveiling="geom",
RCorrection="Rarefy", CheckArguments = TRUE)
```

### Arguments

`Ns` |
A numeric vector containing species abundances. |

`Level` |
The level of interpolation or extrapolation. It may be an an arbitrary sample size (an integer) or a sample coverage (a number between 0 and 1). |

`PCorrection` |
A string containing one of the possible corrections to estimate a probability distribution in |

`Unveiling` |
A string containing one of the possible unveiling methods to estimate the probabilities of the unobserved species in |

`RCorrection` |
A string containing a correction recognized by |

`CheckArguments` |
Logical; if |

### Details

The Abundance Frequency Count (Chao *et al.*, 2015) is the number of species observed each number of times.

It is a way to summarize the species distribution.

It can be estimated at a specified level of interpolation or extrapolation.
Extrapolation relies on the estimation of the estimation of the asymptotic distribution of the community by `as.ProbaVector`

and eq. (5) of Chao et al. (2014).

### Value

A two-column matrix. The first column contains the number of observations, the second one the number of species observed this number of times.

### References

Chao, A., Gotelli, N. J., Hsieh, T. C., Sander, E. L., Ma, K. H., Colwell, R. K., Ellison, A. M (2014). Rarefaction and extrapolation with Hill numbers: A framework for sampling and estimation in species diversity studies. *Ecological Monographs*, 84(1): 45-67.

Chao, A., Hsieh, T. C., Chazdon, R. L., Colwell, R. K., Gotelli, N. J. (2015) Unveiling the Species-Rank Abundance Distribution by Generalizing Good-Turing Sample Coverage Theory. *Ecology* 96(5): 1189-1201.

### See Also

### Examples

```
# Load Paracou data (number of trees per species in two 1-ha plot of a tropical forest
# and their taxonomy)
data(Paracou618)
# Ns is the vector of abundances of the first plot
Ns <- Paracou618.MC$Nsi[, 1]
# Return the abundance frequency count
(AbdFreqCount(Ns) -> afc)
plot(afc, xlab="Number of observations", ylab="Number of species")
lines(afc)
```

*entropart*version 1.6-13 Index]