skip to main content skip to footer

Survey of Studies on Correction for Guessing and Guessing Instructions

Freeman, Paul M.
Publication Year:
Report Number:
ETS Research Memorandum
Document Type:
Page Count:
Subject/Key Words:
Correction for Guessing, Guessing Tests, Literature Reviews, Scoring Formulas, Test Instructions, Test Reliability, Test Validity


The literature on correcting for guessing, on different instructions to students regarding guessing, and their effects on reliability and validity of the tests, was surveyed. Although no broad generalization can be made from the experimental work, conclusions include: 1) The effect of factors such as partial knowledge, positional response tendencies, ability to eliminate one or more alternatives, the lack of independence among items or among alternatives within an item, and varying degrees of willingness to gamble all weaken the validity of the mathematical model; 2) the effect on test validity of instructions to guess or not to guess was indeterminate; 3) to find the optimal correction formula for a given test it is necessary to determine regression weights for Rights, Wrongs and in some cases Omits, which could involve an impractically bulky procedure; and 4) other variables, including speededness of the test, need to be studied further.

Read More