Combines some or all etas into a joint distribution.
The etas must be IIVs and cannot
be fixed. Initial estimates for covariance between the etas is dependent on whether
the model has results from a previous run. In that case, the correlation will
be calculated from individual estimates, otherwise correlation will be set to 10%.
(array(str) (optional)) Sequence of etas or names of etas to combine. If NULL, all etas that are IIVs and
non-fixed will be used (full block). NULL is default.
individual_estimates
(data.frame (optional)) Optional individual estimates to use for calculation of initial estimates
See Also
split_joint_distribution : split etas into separate distributions
if (FALSE) {
model <- load_example_model("pheno")
model$random_variables$etas
model <- create_joint_distribution(model, c('ETA_CL', 'ETA_VC'))
model$random_variables$etas
}