stModel.define: Define a spacetime model object for the `f()` call.

Description

Define a spacetime model object for the f() call.

Usage

stModel.define(
  smesh,
  tmesh,
  model,
  control.priors,
  constr = FALSE,
  debug = FALSE,
  useINLAprecomp = TRUE,
  libpath = NULL
)

Value

objects to be used in the f() formula term in INLA.

Arguments

smesh: a spatial mesh
tmesh: a temporal mesh
model: a three characters string to specify the smoothness alpha (each one as integer) parameters. Currently it considers the 102, 121, 202 and 220 models.
control.priors: a named list with parameter priors. E.g. prior.rs, prior.rt and prior.sigma as vectors with length two (U, a) to define the corresponding PC-prior such that P(r_s<U)=a, P(r_t<U)=a or P(sigma>U)=a. If a=0 then U is taken to be the fixed value of the parameter.
constr: logical to indicate if the integral of the field over the domain is to be constrained to zero. Default value is FALSE.
debug: integer indicating the verbose level. Will be used as logical by INLA.
useINLAprecomp: logical indicating if is to be used shared object pre-compiled by INLA. Not considered if libpath is provided.
libpath: string to the shared object. Default is NULL.

Details

The matrices of the kronecker product in Theorem 4.1 of Lindgren et. al. (2024) are computed with the stModel.matrices and the parameters are as Eq (19-21), but parametrized in log scale.

References

Lindgren et. al. (2024). A diffusion-based spatio-temporal extension of Gaussian Matérn fields. SORT 48 (1), 3-66