R/jkestimates.R

In CDM: Cognitive Diagnosis Modeling

## File Name: jkestimates.R
## File Version: 0.11


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# jkestimates
jkestimates <- function( est, parsM, fayfac )
{
    RR <- ncol(parsM)
    M_pars <- rowMeans( parsM  )
    parsMres <- parsM - M_pars
    # variance covariance matrix of estimators
    vcov_pars <- tcrossprod( parsMres )
    dfr <- data.frame( "est"=est,
            "jkest"=est - fayfac * (RR-1) * ( M_pars - est) )
    dfr$jkse <- sqrt( diag( vcov_pars ))
    res <- list("dfr"=dfr, "vcov_pars"=vcov_pars )
    return(res)
}
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