BMMmodel {bayesmix}

Creates bugs model.

Description

Creates the BUGS-model specification and return the values for the initialization, the prior specification and the observations.

Usage

BMMmodel(y, k, priors, inits = "initsFS", aprioriWeights = 1,
         no.empty.classes = FALSE, restrict = "none", ...)

Arguments

y

a numeric vector.

k

integer indicating the number of segments.

priors

specification of priors by a named list or a BMMpriors object.

inits

specification of initial values by a named list or string indicating the function to be called.

aprioriWeights

specification of prior of the a-priori weights. If aprioriWeights does not have length = k, there is an equal prior for the a-priori weights assumed.

no.empty.classes

logical: should it be prevented that empty classes arise during sampling.

restrict

one of "none", "mu", "tau".

...

further parameters for the function specified in inits.

Details

By default the function initsFS is called for generating initial values. Any other function specified by inits is assumed to have at least x, k and restrict as input parameters.

The parameter restrict indicates if a location-shift model ("tau"), a scale contaminated model ("mu") or a model where both variables vary over components shall be fitted.

If the logical no.empty.classes is TRUE there are observations added to the model that the classes are not empty. This signifies that the likelihood when sampling the class affiliations is changed thus that any data point which is sampled and is the last one in its class stays there.

Value

If y is specified an object of class BMMmodel is returned with components:

inits

named list.

data

named list.

bugs

text for .bug-file with prefix missing.

If y is missing an object of class BMMsetup is returned containing the parameter specifications. When JAGScall is called with this object as model argument, BMMmodel is called with y and the other parameters as input arguments before calling JAGS.

Author(s)

Bettina Gruen

See Also

JAGSrun, initsFS

Examples

data("fish", package = "bayesmix")
model <- BMMmodel(fish, k = 4, priors = list(kind = "independence",
                  parameter = "priorsFish", hierarchical = "tau"),
                  initialValues = list(S0 = 2))
model