What is Spearman Brown reliability index?
Thereof, what does the Spearman Brown formula do?
The Spearman–Brown prediction formula, also known as the Spearman–Brown prophecy formula, is a formula relating psychometric reliability to test length and used by psychometricians to predict the reliability of a test after changing the test length.
Also to know, what is reliability index?
Item reliability is simply the product of the standard deviation of item scores and a correlational discrimination index (Item-Total Correlation Discrimination in the Item Analysis Report). So item reliability reflects how much the item is contributing to total score variance.
Correlate the test scores of the two administrations of the same test. – Parallel Forms Reliability: Determines how comparable are two different versions of the same measure. To calculate: Administer the two tests to the same participants within a short period of time. Correlate the test scores of the two tests.