rmhcontrol
Set Control Parameters for Metropolis-Hastings Algorithm.
Sets up a list of parameters controlling the iterative behaviour of the Metropolis-Hastings algorithm.
Usage
rmhcontrol(...) ## S3 method for class 'default':
rmhcontrol(\dots, p=0.9, q=0.5, nrep=5e5,
expand=NULL, periodic=NULL, ptypes=NULL,
x.cond=NULL, fixall=FALSE, nverb=0,
nsave=NULL, nburn=nsave, track=FALSE)
Arguments
- ...
- Arguments passed to methods.
- p
- Probability of proposing a shift (as against a birth/death).
- q
- Conditional probability of proposing a death given that a birth or death will be proposed.
- nrep
- Total number of steps (proposals) of Metropolis-Hastings algorithm that should be run.
- expand
- Simulation window or expansion rule.
Either a window (object of class
"owin"
) or a numerical expansion factor, specifying that simulations are to be performed in a domain other than the original data window, then clipped to th - periodic
- Logical value (or
NULL
) indicating whether to simulate ``periodically'', i.e. identifying opposite edges of the rectangular simulation window. ANULL
value means ``undecided.'' - ptypes
- For multitype point processes, the distribution of the mark attached to a new random point (when a birth is proposed)
- x.cond
- Conditioning points for conditional simulation.
- fixall
- (Logical) for multitype point processes, whether to fix the number of points of each type.
- nverb
- Progress reports will be printed every
nverb
iterations - nsave,nburn
- If these values are specified, then
intermediate states of the simulation algorithm will be saved
every
nsave
iterations, after an initial burn-in period ofnburn
iterations. - track
- Logical flag indicating whether to save the transition history of the simulations.
Details
The Metropolis-Hastings algorithm, implemented as rmh
,
generates simulated realisations of point process models.
The function rmhcontrol
sets up a list of parameters which control the
iterative behaviour
and termination of the Metropolis-Hastings algorithm, for use in a
subsequent call to rmh
. It also checks that the
parameters are valid.
(A separate function rmhstart
determines the initial state of the algorithm,
and rmhmodel
determines the model to be simulated.)
The parameters are as follows: [object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Value
- An object of class
"rmhcontrol"
, which is essentially a list of parameter values for the algorithm. There is aprint
method for this class, which prints a sensible description of the parameters chosen.
References
Geyer, C.J. (1999) Likelihood Inference for Spatial Point Processes. Chapter 3 in O.E. Barndorff-Nielsen, W.S. Kendall and M.N.M. Van Lieshout (eds) Stochastic Geometry: Likelihood and Computation, Chapman and Hall / CRC, Monographs on Statistics and Applied Probability, number 80. Pages 79--140.
See Also
Examples
# parameters given as named arguments
c1 <- rmhcontrol(p=0.3,periodic=TRUE,nrep=1e6,nverb=1e5)
# parameters given as a list
liz <- list(p=0.9, nrep=1e4)
c2 <- rmhcontrol(liz)
# parameters given in rmhcontrol object
c3 <- rmhcontrol(c1)