GGUM2004: AWindows-Based Program to Estimate Parameters in the Generalized Graded Unfolding Model

The GGUM2004 computer program estimates parameters for a family of unidimensional unfolding item response theory (IRT) models. These unfolding IRT models predict higher item scores to the extent that a respondent is located close to an item on an underlying latent continuum. This prediction is often consistent with responses to traditional Thurstone or Likert attitude questionnaires. Unfolding IRT models can also be used to measure individual differences in preference and certain developmental processes in which behaviors/cognitions occur in unique stages.