ConQuest
Wu, M. L., Adams, R. J., Wilson, M. R., Haldane, S.A.
www.conquestwebsite.com
Generalized Item Response Modelling Software
ConQuest is a computer program developed for fitting item response and latent regression models. It provides a comprehensive and flexible range of item response models to analysts, allowing them to examine the properties of performance assessments, traditional assessments and rating scales. ConQuest also makes available, to the wider measurement and research community, the most up to date psychometric methods of multifaceted item response models, multidimensional item response models, latent regression models and drawing plausible values.
What are the models that ConQuest can fit?ConQuest brings together in a single program a wide variety of item response models (including multidimensional models) and provides an integration of item response and regression analysis.
Rasch's Simple Logistic Model
Rating Scale Model
Partial Credit Model
Ordered Partition Model
Linear Logistic Test Model
Multifaceted Models
Generalized Unidimensional Models
Multidimensional Item Response Models
Latent Regression Models
How does ConQuest fit these models?
ConQuest produces marginal maximum likelihood MMLE estimates for the parameters of the models listed. The estimation algorithms used are adaptations of the quadrature method described by Bock and Aitken (1981) and the Monte Carlo method of Volodin and Adams (1995). The fit of the models is ascertained by generalizations of the Wright and Masters (1982) residual-based methods that were developed by Wu (1997).
Some applications of ConQuest
Performing item analysis
Examining differential item functioning
Exploring rater effects
Estimating latent correlations
Testing dimensionality
Drawing plausible values
Demonstration versions can be downloaded from http://www.acer.edu.au/quest