03119nas a2200277   4500008004100000020002200041245010900063210006900172250001500241260000800256300001200264490000700276520221700283653002902500653002002529653002502549653002102574653001502595653002802610653001102638653002502649100001702674700001502691700001202706856012302718       2006                        eng d  a0214-9915 (Print)00aMaximum information stratification method for controlling item exposure in computerized adaptive testing0 aMaximum information stratification method for controlling item e  a2007/02/14  cFeb  a156-1590 v183 aThe proposal for increasing the security in Computerized Adaptive Tests that has received most attention in recent years is the a-stratified method (AS - Chang and Ying, 1999): at the beginning of the test only items with low discrimination parameters (a) can be administered, with the values of the a parameters increasing as the test goes on. With this method, distribution of the exposure rates of the items is less skewed, while efficiency is maintained in trait-level estimation. The pseudo-guessing parameter (c), present in the three-parameter logistic model, is considered irrelevant, and is not used in the AS method. The Maximum Information Stratified (MIS) model incorporates the c parameter in the stratification of the bank and in the item-selection rule, improving accuracy by comparison with the AS, for item banks with a and b parameters correlated and uncorrelated. For both kinds of banks, the blocking b methods (Chang, Qian and Ying, 2001) improve the security of the item bank.Método de estratificación por máxima información para el control de la exposición en tests adaptativos informatizados. La propuesta para aumentar la seguridad en los tests adaptativos informatizados que ha recibido más atención en los últimos años ha sido el método a-estratificado (AE - Chang y Ying, 1999): en los momentos iniciales del test sólo pueden administrarse ítems con bajos parámetros de discriminación (a), incrementándose los valores del parámetro a admisibles según avanza el test. Con este método la distribución de las tasas de exposición de los ítems es más equilibrada, manteniendo una adecuada precisión en la medida. El parámetro de pseudoadivinación (c), presente en el modelo logístico de tres parámetros, se supone irrelevante y no se incorpora en el AE. El método de Estratificación por Máxima Información (EMI) incorpora el parámetro c a la estratificación del banco y a la regla de selección de ítems, mejorando la precisión en comparación con AE, tanto para bancos donde los parámetros a y b correlacionan como para bancos donde no. Para ambos tipos de bancos, los métodos de bloqueo de b (Chang, Qian y Ying, 2001) mejoran la seguridad del banco.10a*Artificial Intelligence10a*Microcomputers10a*Psychological Tests10a*Software Design10aAlgorithms10aChi-Square Distribution10aHumans10aLikelihood Functions1 aBarrada, J R1 aMazuela, P1 aOlea, J  uhttp://www.iacat.org/content/maximum-information-stratification-method-controlling-item-exposure-computerized-adaptive01697nas a2200229   4500008004100000020004100041245006400082210006200146250001500208260000800223300001100231490000700242520102000249653003101269653002501300653001001325653001101335653001101346653000901357100001601366856008501382       1995                        jpn d  a0021-5236 (Print)0021-5236 (Linking)00aA study of psychologically optimal level of item difficulty0 astudy of psychologically optimal level of item difficulty  a1995/02/01  cFeb  a446-530 v653 aFor the purpose of selecting items in a test, this study presented a viewpoint of psychologically optimal difficulty level, as well as measurement efficiency, of items. A paper-and-pencil test (P & P) composed of hard, moderate and easy subtests was administered to 298 students at a university. A computerized adaptive test (CAT) was also administered to 79 students. The items of both tests were selected from Shiba's Word Meaning Comprehension Test, for which the estimates of parameters of two-parameter item response model were available. The results of P & P research showed that the psychologically optimal success level would be such that the proportion of right answers is somewhere between .75 and .85. A similar result was obtained from CAT research, where the proportion of about .8 might be desirable. Traditionally a success rate of .5 has been recommended in adaptive testing. In this study, however, it was suggested that the items of such level would be too hard psychologically for many examinees.10a*Adaptation, Psychological10a*Psychological Tests10aAdult10aFemale10aHumans10aMale1 aFujimori, S  uhttp://www.iacat.org/content/study-psychologically-optimal-level-item-difficulty