Draws plausible parameters from a model using parametric sampling (if the information matrix
was computed) or via bootstrap sampling. Primarily for use with the DRF function.
Usage
draw_parameters(
mod,
draws,
method = c("parametric", "boostrap"),
redraws = 20,
verbose = FALSE,
...
)Arguments
- mod
estimated single or multiple-group model
- draws
number of draws to obtain
- method
type of plausible values to obtain. Can be 'parametric', for the parametric sampling scheme which uses the estimated information matrix, or 'boostrap' to obtain values from the
bootfunction. Default is 'parametric'- redraws
number of redraws to perform when the given parameteric sample does not satisfy the upper and lower parameter bounds. If a valid set cannot be found within this number of draws then an error will be thrown
- verbose
logical; include additional information in the console?
- ...
additional arguments to be passed
Value
returns a draws x p matrix of plausible parameters, where each row correspeonds to a single set
Examples
if (FALSE) { # \dontrun{
set.seed(1234)
n <- 40
N <- 500
# only first 5 items as anchors
model <- 'F = 1-40
CONSTRAINB = (1-5, a1), (1-5, d)'
a <- matrix(1, n)
d <- matrix(rnorm(n), n)
group <- c(rep('Group_1', N), rep('Group_2', N))
## -------------
# groups completely equal
dat1 <- simdata(a, d, N, itemtype = 'dich')
dat2 <- simdata(a, d, N, itemtype = 'dich')
dat <- rbind(dat1, dat2)
mod <- multipleGroup(dat, model, group=group, SE=TRUE,
invariance=c('free_means', 'free_var'))
param_set <- draw_parameters(mod, 100)
head(param_set)
} # }