Generate a realisation of the area-interaction process using the alternating Gibbs sampler. Applies only when the interaction parameter \(eta\) is greater than 1.
ragsAreaInter(beta, eta, r, …,
win = NULL, bmax = NULL, periodic = FALSE, ncycles = 100)
First order trend. A number, a pixel image (object of class
"im"
), or a function(x,y)
.
Interaction parameter (canonical form) as described in
the help for AreaInter
.
A number greater than 1.
Disc radius in the model. A number greater than 1.
Additional arguments for beta
if it is a function.
Simulation window. An object of class "owin"
.
(Ignored if beta
is a pixel image.)
Optional. The maximum possible value of beta
,
or a number larger than this.
Logical value indicating whether to treat opposite sides of the simulation window as being the same, so that points close to one side may interact with points close to the opposite side. Feasible only when the window is a rectangle.
Number of cycles of the alternating Gibbs sampler to be performed.
A point pattern (object of class "ppp"
).
This function generates a simulated realisation of the
area-interaction process (see AreaInter
)
using the alternating Gibbs sampler (see rags
).
It exploits a mathematical relationship between the
(unmarked) area-interaction process and the two-type
hard core process (Baddeley and Van Lieshout, 1995;
Widom and Rowlinson, 1970). This relationship only holds
when the interaction parameter eta
is greater than 1
so that the area-interaction process is clustered.
The parameters beta,eta
are the canonical parameters described
in the help for AreaInter
.
The first order trend beta
may be a constant, a function,
or a pixel image.
The simulation window is determined by beta
if it is a pixel
image, and otherwise by the argument win
(the default is the
unit square).
Baddeley, A.J. and Van Lieshout, M.N.M. (1995). Area-interaction point processes. Annals of the Institute of Statistical Mathematics 47 (1995) 601--619.
Widom, B. and Rowlinson, J.S. (1970). New model for the study of liquid-vapor phase transitions. The Journal of Chemical Physics 52 (1970) 1670--1684.
# NOT RUN {
plot(ragsAreaInter(100, 2, 0.07, ncycles=15))
# }
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