sim.pdata {AHMbook}R Documentation

Simulate non-hierarchical point transect (= point count) data

Description

Function simulates coordinates of individuals on a square with a count location at the center point.

Usage

sim.pdata(N = 1000, sigma = 1, B = 3, keep.all = FALSE, show.plot = TRUE)

Arguments

N

total population size in the square

sigma

scale of half-normal detection function

B

circle radius; the data are simulated over a square of side 2 * B, but individuals outside the circle of radius B are not detected.

keep.all

if TRUE, the data for all individuals are returned; if FALSE, only for individuals detected.

show.plot

choose whether to show plots or not. Set to FALSE when using function in simulations.

Value

A list with the following elements:

N

total population size in the square

sigma

scale of half-normal detection function

B

circle radius

u1, u2

the x and y coordinates of each of the individuals

d

the distance of each individual from the center of the circle

y

a 0/1 indicator showing whether each individual is detected or not, a vector of length N

N.real

the realized number of individuals within the circle of radius B

Author(s)

Marc Kéry & Andy Royle

References

Kéry, M. & Royle, J.A. (2016) Applied Hierarchical Modeling in Ecology AHM1 - 8.2.5.1.

Examples

# Simulate a data set with the default arguments and look at the structure of the output:
tmp <- sim.pdata()
str(tmp)

[Package AHMbook version 0.2.3 Index]