ABSTRACT
The Rasch rating-scale model (RSM) is a member of the class of Rasch models (Rasch, 1961;Andersen, 1977;Andrich, 2005). Its application is particularly relevant when responses to items are in ordered categories.Table 5.1 shows three such formats, each in four categories. Also known as aLikert (1932), format it is an extension of the dichotomous response format and is used when more information may be obtained than from a dichotomous format. In elementary applications, the categories in the intended order are scored with successive integers, beginning with zero (0), and the scores of a person on multiple items of a test or questionnaire summed to characterize a person. In more-advanced applications, a probabilistic model, such as the RSM is applied. Examples of Ordered Category Assessments in a Rating-Scale Format
Strongly disagree
Disagree
Agree
Strongly agree
Never
Sometimes
Often
Always
Fail
Pass
Credit
Distinction
