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WLErel.RdFunctions for computing reliability estimates.
WLErel(theta, error, w=rep(1, length(theta)), select=NULL) EAPrel(theta, error, w=rep(1, length(theta)), select=NULL)
| theta | Vector with theta estimates |
|---|---|
| error | Vector with standard errors of theta estimates |
| w | Optional vector of person weights |
| select | Optional vector for selecting cases |
The reliability formulas follow Adams (2005). Let \(v\) denote
the variance of theta estimates and let \(s\) denote
the average of the squared error. Then, the WLE reliability is
defined as \(1-s/v=(v-s)/v\) while the EAP reliability is defined as
\(1 - s/(s+v)=v/(s+v)\).
Numeric value
Adams, R. J. (2005). Reliability as a measurement design effect. Studies in Educational Evaluation, 31(2), 162-172. doi: 10.1016/j.stueduc.2005.05.008
############################################################################# # EXAMPLE 1: Toy example for reliability functions ############################################################################# set.seed(9897) N <- 100 # simulate theta and error SDs x <- stats::rnorm(N,sd=2) error <- stats::runif(N, .7, 1.3) # compute WLE reliability WLErel(x,error) # compute EAP reliaility EAPrel(x,error)