Browsing by Author "McKinley, Robert L."

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    A comparison of several goodness-of-fit statistics
    (1985) McKinley, Robert L.; Mills, Craig N.
    A study was conducted to evaluate four goodness-of- fit procedures using data simulation techniques. The procedures were evaluated using data generated according to three different item response theory models and a factor analytic model. Three different distributions of ability were used, as were three different sample sizes. It was concluded that the likelihood ratio chi-square procedure yielded the fewest erroneous rejections of the hypothesis of fit, whereas Bock’s chi-square procedure yielded the fewest erroneous acceptances of fit. It was found that sample sizes somewhere between 500 and 1,000 were best. Shifts in the mean of the ability distribution were found to cause minor fluctuations, but they did not appear to be a major issue.
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    The discriminating power of items that measure more than one dimension
    (1991) Reckase, Mark D.; McKinley, Robert L.
    Determining a correct response to many test items frequently requires more than one ability. This paper describes the characteristics of items of this type by proposing generalizations of the item response theory concepts of discrimination and information. The conceptual framework for these statistics is presented, and the formulas for the statistics are derived for the multidimensional extension of the two-parameter logistic model. Use of the statistics is demonstrated for a form of the ACT Mathematics Usage Test. Index terms: item discrimination, item information, item response theory, multidimensional item response theory.