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exametrika (version 1.1.0)

ITBiserial: Item-Total Biserial Correlation

Description

The Item-Total Biserial Correlation computes the biserial correlation between each item and the total score. This function is applicable only to binary response data.

This correlation provides a measure of item discrimination, indicating how well each item distinguishes between high and low performing examinees.

Usage

ITBiserial(U, na = NULL, Z = NULL, w = NULL, ...)

Value

A numeric vector of item-total biserial correlations. Values range from -1 to 1, where:

  • Values near 1: Strong positive discrimination

  • Values near 0: No discrimination

  • Negative values: Potential item problems

Arguments

U

U is a data matrix of the type matrix or data.frame.

na

na argument specifies the numbers or characters to be treated as missing values.

Z

Z is a missing indicator matrix of the type matrix or data.frame

w

w is item weight vector

...

Internal parameters for maintaining compatibility with the binary data processing system. Not intended for direct use.

Examples

Run this code
# using sample dataset
ITBiserial(J15S500)

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