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Spearman–Brown prophecy formula

the mathematical formulation of a basic tenet of classical test theory concerning the length (number of items) of a test and its influence on reliability, whereby increasing the number of items with similar content results in increased reliability for the test, and decreasing the number of items leads to decreased reliability. The formula allows a researcher to estimate the gains or losses in reliability that would occur with changes in test size. Also called Spearman–Brown prediction formula. [Charles Spearman; W. Brown, 20th-century British psychologist]

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Psychology term of the day

December 26th 2024