Calculate the variances of items in a Testlet
# S4 method for Testlet
var(x, y = NULL, na.rm = FALSE, use)
Item variances at given theta will be returned.
An Testlet-class
object containing the item
parameters of the testlet.
A numeric vector containing the ability parameters (i.e. theta).
Ignored for var(Testlet, ...)
Ignored for var(Testlet, ...)
Emre Gonulates