Distractor efficiency analysis on a spreadsheet |
James Dean Brown University of Hawai'i at Manoa |
Screen 1: The Setup for Distractor Efficiency Analysis
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Item Analysis in a Spreadsheet
Screen 2: Formulas for Distractor Efficiency Analysis of Item One
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Cell B21 of Screen 2 shows how the IF for item one is calculated using = COUNTIF (B2:B19, "A")/16, or the average of correct answers for all students taking the item. Simply enter the formula shown in cell B21 and hit the <enter> key. The number .94 should appear (as shown in the same cell in Screen 1). Screen 2 also shows the calculation of IF_{upper} using a similar formula in cell B22, but for the range that includes only the top five students (B2 : B6); calculation of IF_{lower} in cell B23 is similar, but for the bottom five students (B15 : B19). Cell B24 shows the calculation of ID, which is IF_{upper} - IF_{lower}, or in this case, = B22 - B23.[ p. 22 ]
Brown, J. D. (1996). Testing in language programs. Upper Saddle River, NJ: Prentice Hall.
Brown, J. D. (translated into Japanese by M. Wada). (1999). Gengo tesuto no kisochishiki [Basic knowledge of language testing]. Tokyo: Taishukan Shoten. Brown, J. D. (2000). Statistics Corner. Questions and answers about language testing statistics (How can we calculate item statistics for weighted items?). Shiken: JALT Testing & Evaluation SIG Newsletter, 3(2), 19-21. Retrieved on July 1, 2002 from the World Wide Web at http://jalt.org/test/bro_6.htm. |
Where to Submit Questions: |
Please submit questions for this column to the following address: |
JD Brown Department of Second Language Studies University of Hawai'i at Manoa 1890 East-West Road Honolulu, HI 96822 USA |
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