Anna Brown, PhD

Personal page

Fitting a Thurstonian IRT model to forced-choice data using Mplus

Here you can download SUPPLEMENTARY MATERIALS for the article
Brown, A. and Maydeu-Olivares, A. (2012). Fitting a Thurstonian IRT model to forced-choice data using Mplus. Behavior Research Methods, 44, 1135–1147. DOI: 10.3758/s13428-012-0217-x

In this paper, we provide step-by-step tutorial for coding forced-choice responses, specifying a Thurstonian IRT model appropriate for the design used, assessing its fit, and scoring individuals on psychological attributes. Estimation and scoring is performed using Mplus, and a very straightforward Excel macro is provided that writes full Mplus input files for any forced-choice design. Armed with these tools, using a forced-choice design is now as easy as using ratings. 


  • The Excel macro automates Mplus syntax creation
  • The User Guide helps navigate through specifying forced-choice models in the Excel macro
  • The data and Mplus scripts for the numerical examples in the paper can be used as templates for building and testing your own models