Wald test of differential test functioning.

A Wald test of the difference between the unweighted mean of the y_fun and robust scaling parameter from rdif. Called internally by rdif

Usage

delta_test(object, theta = NULL, k = NULL, fun = "d_fun3")

Arguments

object

either the output of get_model_parms or an rdif object from rdif.

theta

the estimated scaling parameter from rdif. Not needed when object is an rdif object.

k

the tuning parameter from rdif. Not needed when object is an rdif object.

fun

one of c("a_fun1", "a_fun2", "d_fun1", "d_fun2", "d_fun3"). See description for details.

Value

A data.frame that contains the output of the test.

Examples

#
# \donttest{
mod <- rdif(mle = rdif.eg)
#> Error: object 'rdif.eg' not found
delta_test(object = rdif.eg, theta = mod$est, k = mod$k)
#> Error: object 'rdif.eg' not found
delta_test(mod)
#> Error: object 'mod' not found
# }