steigerStat function

steigerStat

Function to cacluate the Steiger statistic. The Steiger statistic is a test of independance of the standardised residuals ((O-E)/sqrt(Var(E))), where Var(E) = p(x)/(1-p(x)).

steigerStat(myDat, q3Adj = TRUE, fisher = TRUE, dfAdj = FALSE, tpm)

Arguments

• myDat: A data frame or matrix containing standardised residuals.
• q3Adj: A bool indicating whether the Q3 correction should be applied.
• fisher: A bool indicating whether the Fisher Transform should be applied.
• dfAdj: A bool indicating whether the df should be adjusted for sample size, L, and targeting. If dfAdj is TRUE, then you must pass in the optional argument tmp (test-person match)
• tpm: A number indicating the test-person match, where 0 indicates that mean item difficulty is equal to mean person ability, and -1 indcates that mean item difficulty is 1 logit below mean person ability.

Returns

A list of class "steigerStat" with the Steiger Statistic, correlation matrix, and chi square test.