boot.mirt {mirt} | R Documentation |
Given an internal mirt object estimate the bootstrapped standard errors. It may
be beneficial to run the computations using multi-core architecture (e.g., the parallel
package). Parameters are organized from the freely estimated values in mod2values(x)
(equality constraints will also be returned in the bootstrapped estimates).
boot.mirt(x, R = 100, boot.fun = NULL, technical = NULL, ...)
x |
an estimated model object |
R |
number of draws to use (passed to the |
boot.fun |
a user-defined function used to extract the information from the bootstrap
fitted models. Must be of the form |
technical |
technical arguments passed to estimation engine. See |
... |
additional arguments to be passed on to |
Phil Chalmers rphilip.chalmers@gmail.com
Chalmers, R., P. (2012). mirt: A Multidimensional Item Response Theory Package for the R Environment. Journal of Statistical Software, 48(6), 1-29. doi: 10.18637/jss.v048.i06
## Not run: # standard mod <- mirt(Science, 1) booted <- boot.mirt(mod, R=20) plot(booted) booted #run in parallel using snow back-end using all available cores mod <- mirt(Science, 1) booted <- boot.mirt(mod, parallel = 'snow', ncpus = parallel::detectCores()) booted #### # bootstrapped CIs for standardized factor loadings boot.fun <- function(mod){ so <- summary(mod, verbose=FALSE) as.vector(so$rotF) } # test to see if it works before running boot.fun(mod) # run booted.loads <- boot.mirt(mod, boot.fun=boot.fun) booted.loads ## End(Not run)