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# r.pbis, personal point-biserial correlation (Brennan, 1980, cited in Harhisch & Linn, 1981):
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r.pbis <- function(matrix,
NA.method="Pairwise", Save.MatImp=FALSE,
IP=NULL, IRT.PModel="2PL", Ability=NULL, Ability.PModel="ML", mu=0, sigma=1)
{
matrix <- as.matrix(matrix)
N <- dim(matrix)[1]; I <- dim(matrix)[2]
IP.NA <- is.null(IP); Ability.NA <- is.null(Ability)
# Sanity check - Data matrix adequacy:
Sanity.dma(matrix, N, I)
# Dealing with missing values:
res.NA <- MissingValues(matrix, NA.method, Save.MatImp, IP, IRT.PModel, Ability, Ability.PModel, mu, sigma)
matrix <- res.NA[[1]]
# Sanity check - Perfect response vectors:
part.res <- Sanity.prv(matrix, N, I)
NC <- part.res$NC
all.0s <- part.res$all.0s
all.1s <- part.res$all.1s
matrix.sv <- matrix
matrix <- part.res$matrix.red
# Compute PFS:
pi <- colMeans(matrix.sv, na.rm = TRUE)
N.red <- dim(matrix)[1]
res.red <- as.vector(cor(t(matrix), pi, use = "pairwise.complete.obs"))
# Compute final PFS vector:
res <- final.PFS(res.red, all.0s, all.1s, N)
# Export results:
export.res.NP(matrix.sv, N, res, "r.pbis", part.res, Ncat=2, NA.method,
IRT.PModel, res.NA[[2]], Ability.PModel, res.NA[[3]], IP.NA, Ability.NA, res.NA[[4]])
}