playRN {AHMbook} R Documentation

## Function to play Royle-Nichols (RN) model

### Description

Function generates replicated count data under the binomial N-mixture model of Royle (2004), then 'degrades' the counts to detection/nondetection and fits the Royle-Nichols (RN) model (Royle & Nichols 2003) using unmarked and estimates site-specific abundance.

### Usage

```playRN(M = 267, J = 3, mean.abundance = 1, mean.detection = 0.3,
show.plots = TRUE, verbose = TRUE)
```

### Arguments

 `M` The number of sites. `J` The number of visits to each site. `mean.abundance` Expected abundance at each site. `mean.detection` Expected detection at each survey at each site. `show.plots` choose whether to show plots or not. Set to FALSE when using function in simulations. `verbose` if FALSE, output to the console will be suppressed.

### Value

A list with the following elements:

 `nsites ` The number of sites, equal to `M` in the input `nvisits ` The number of visits, equal to `J` in the input `coef ` A named vector of coefficients for the linear models for expected number and detection probability `slope ` Slope of the regression of the estimated number on the true number; 1 if the model is perfect

### Author(s)

Marc Kéry & Andy Royle

### References

Royle, J.A. & Nichols, J.D. (2003) Estimating abundance from repeated presence-absence data or point counts, Ecology, 84, 777-790.

Royle, J.A. (2004) N-mixture models for estimating population size from spatially replicated counts, Biometrics, 60, 108-115.

Kéry, M. & Royle, J.A. (2016) Applied Hierarchical Modeling in Ecology AHM1 - 6.13.1.

### Examples

```# Run a simulation with the default arguments and look at the results:
playRN()

# Execute the function using various settings
playRN(M = 100, J = 3, mean.abundance = 0.1)  # Increasing abundance
playRN(M = 100, J = 3, mean.abundance = 1)
playRN(M = 100, J = 3, mean.abundance = 5)
playRN(M = 100, J = 3, mean.detection = 0.3)  # Increasing detection
playRN(M = 100, J = 3, mean.detection = 0.5)
playRN(M = 100, J = 3, mean.detection = 0.7)
playRN(M = 100, J = 20)                       # More visits
playRN(M = 1000, J = 3)                       # More sites

```

[Package AHMbook version 0.2.3 Index]