GLBFind

GLBFIND computes the Greatest Lower Bound (GLB) to the reliability of a test. This statistic is based on the covariance or correlation matrix of the test items. Under the assumptions of classical test theory it is the highest possible lower bound that can be derived from a single test administration.
However, when estimated from a sample, the estimated GLB is severely biased due to a phenomenon known as capitalization on chance. Therefore GLBFind performs a correction procedure that removes the bias from the estimate.

Input:

* covariance matrix
* correlation matrix
* raw data