The improvement in reliability gained by adding additional "good" test items can be precisely calculated using the ________ formula.
A) Pearson Product Moment
B) alpha
C) Tucker-Lewis
D) Spearman-Brown

Question

Quizplus · Accepted Answer

The Spearman-Brown formula is used to predict the effect on test reliability of adding or removing items from a test. It is specifically used to estimate the new reliability when the test length is changed, under the assumption that the additional items are of similar quality to the original items.

The Improvement in Reliability Gained by Adding Additional "Good" Test