The Impact of Correction for Guessing Formula on MC and Yes/No Vocabulary Tests' Scores

A standard correction for random guessing (cfg) formula on multiple-choice and Yes/Noexaminations was examined retrospectively in the scores of the intermediate female EFL learners in an English language school. The correctionwas a weighting formula for points awarded for correct answers,incorrect answers, and unanswered questions so that the expectedvalue of the increase in test score due to guessing was zero. The researcher compared uncorrected and corrected scores on examinationsusing multiple-choice and Yes/No formats. These short-answer formats eliminatedor at least greatly reduced the potential for guessing the correctanswer. The expectation for students to improve their grade by guessingon multiple-choice and Yes/No format examinations is well known. The researcher examined a method for correcting for random guessing (cfg) " no knowledge" on multiple- choice and Yes/No vocabulary examinations by comparing application and non-application of correction for guessing (cfg) formula on scores on these examinations. It was done to determine whether the test takers really knew the correct answer, or they had resorted to a kind of guessing. This study represented a unique opportunity to compare scores from multiple-choice and Yes/No examinations in a settingin which students were given the same number of questions ineach of the two format types testing their knowledge over thesame subject matter. The results of this study indicated that the significant differences were highlighted between the subjects' scores when cfg formula was applied and when it was not.