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Browsing by Author "Boekkooi-Timminga, Ellen"

Now showing 1 - 2 of 2
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    A cluster-based method for test construction
    (1990) Boekkooi-Timminga, Ellen
    Several methods for optimal test construction from item banks have recently been proposed using information functions. The main problem with these methods is the large amount of time required to identify an optimal test. In this paper, a new method is presented for the Rasch model that considers groups of interchangeable items, instead of individual items. The process of item clustering is described, the cluster-based test construction model is outlined, and the computational procedure and results are given. Results indicate that this method produces accurate results in small amounts of time. Index terms: information functions, item banking, item response theory, linear programming, test construction.
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    A zero-one programming approach to Gulliksen's matched random subtests method
    (1988) Van der Linden, Wim J.; Boekkooi-Timminga, Ellen
    Gulliksen’s matched random subtests method is a graphical method to split a test into parallel test halves. The method has practical relevance because it maximizes coefficient α as a lower bound to the classical test reliability coefficient. In this paper the same problem is formulated as a zero-one programming problem, the advantage being that it can be solved by computer algorithms that already exist. It is shown how the procedure can be generalized to split tests of any length. The paper concludes with an empirical example comparing Gulliksen’s original hand-method with the zero-one programming version. Index terms: Classical test theory, Gulliksen’s matched random subtests method, Item matching, Linear programming, Parallel tests, Test reliability, Zero-one programming.