| 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)