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Evaluation Of Item Parameter Recovery Estimation By Acer Conquest Software, Luc T. Le, Ray Adams
Evaluation Of Item Parameter Recovery Estimation By Acer Conquest Software, Luc T. Le, Ray Adams
Professor Ray Adams
ACER ConQuest (Adams, Wu, and Wilson, 2012) has been popularly used for analysing testing and assessment data. Two of the most common estimation methods for Rasch measurement models (Rasch, 1960/1980) are available in this software, marginal maximum likelihood estimation (MML) and joint maximum likelihood estimation (JML). This study is concerned with item parameter recovery for the dichotomous Rasch model. Our primary focus is on comparing JML and MML when the assumptions of MML are violated, that is the abilities are not sampled from the distribution that is assumed in the estimation.
The Estimation Of Polytomous Item Response Models With Many Dimensions, Nikolai Volodin, Ray J. Adams
The Estimation Of Polytomous Item Response Models With Many Dimensions, Nikolai Volodin, Ray J. Adams
Professor Ray Adams
Identification conditions and an improved estimation method for a D-dimensional mixed coefficients multinomial logit model are discussed. This model is a generalisation of the Adams and Wilson (1997) random coefficients multinomial logit and it can be used to fit multdimensional forms of a wide range of Rasch measurement models. The computational demands of the numerical integration required in fitting such models have limited previous implementations to three and perhaps four-dimensional problems (Glas, 1992; Adams, Wilson and Wang, 1997). This paper illustrates a Monte Carlo integration method that permits the estimation of models with much higher dimensionality. The example in this …