R/tam_itempartable.R

In TAM: Test Analysis Modules

## File Name: tam_itempartable.R
## File Version: 9.133



#--- create table of item parameters
tam_itempartable <- function( resp, maxK, AXsi, B, ndim,
            resp.ind, rprobs=NULL, n.ik=NULL, pi.k=NULL, order=FALSE,
            pweights=rep(1,nrow(resp) ) )
{

    if ( is.null(dimnames(B)[[1]] ) ){
        dimnames(B)[[1]] <- colnames(resp)
    }

    item1 <- data.frame( "item"=dimnames(B)[[1]] )
    item1$N <- colSums(resp.ind*pweights)
    item1$M <- colSums(resp.ind * resp * pweights, na.rm=TRUE) / colSums( resp.ind*pweights )
    maxKi <- rowSums( 1 - is.na(AXsi) ) - 1
    I <- nrow(item1)
    item1$xsi.item <- - AXsi[ cbind(1:I, maxKi+1) ] / maxKi

    #--- Item fit
    # probs ... [ classes, items, categories ]
    # probs <- aperm( rprobs, perm=c(3,1,2))
    # pi.k <- matrix( pi.k, ncol=1 )
    b0 <- sum( B[, 1, ], na.rm=TRUE )
    a0 <- 0
    if ( b0 + a0 > 0 ){
        kvec <- 0:(maxK-1)
    } else {
        kvec <- 1:(maxK-1)
    }
    for (kk in kvec){
        item1[, paste0("AXsi_.Cat", kk) ] <- - AXsi[,kk+1]
    }
    for (kk in kvec){
        for (dd in 1:ndim){
            item1[, paste0("B.Cat", kk,".Dim",dd) ] <- B[,kk+1,dd]
        }
    }
    item1 <- item1[ item1$N > 0, ]
    # rownames(item1) <- NULL
    rownames(item1) <- paste( item1$item )

    #--- ordering rows for items
    if (order){
        item1 <- item1[ order( paste(item1$item)), ]
    }
    #*** substitute -99 by missing
    item1[ item1==-99 ] <- NA
    return(item1)
}


.TAM.itempartable <- tam_itempartable