01688nas a2200217   4500008004100000020002200041245008000063210006900143260002600212300001200238490000700250520095600257653003401213653002701247653002301274653002901297100001601326700001801342700001301360856009701373       2007                        eng d  a0146-6216 (Print)00aTest design optimization in CAT early stage with the nominal response model0 aTest design optimization in CAT early stage with the nominal res  bSage Publications: US  a213-2320 v313 aThe early stage of computerized adaptive testing (CAT) refers to the phase of the trait estimation during the administration of only a few items. This phase can be characterized by bias and instability of estimation. In this study, an item selection criterion is introduced in an attempt to lessen this instability: the D-optimality criterion. A polytomous unconstrained CAT simulation is carried out to evaluate this criterion's performance under different test premises. The simulation shows that the extent of early stage instability depends primarily on the quality of the item pool information and its size and secondarily on the item selection criteria. The efficiency of the D-optimality criterion is similar to the efficiency of other known item selection criteria. Yet, it often yields estimates that, at the beginning of CAT, display a more robust performance against instability. (PsycINFO Database Record (c) 2007 APA, all rights reserved)10acomputerized adaptive testing10anominal response model10arobust performance10atest design optimization1 aPassos, V L1 aBerger, M P F1 aTan, F E  uhttp://www.iacat.org/content/test-design-optimization-cat-early-stage-nominal-response-model