Measuring teacher dispositions with different item structures: An application of the Rasch model to a complex accreditation requirement.

The construct of dispositions is defined in national standards, and colleges of education are required to assess candidate dispositions to meet accreditation requirements. Similarly, there is a need to review teacher dispositions in making hiring decisions about teachers, although this need may not yet be realized. Measurement is virtually non-existent in the area of teacher dispositions. On-line reviews of college accreditation reports indicate that colleges are attempting to assess dispositions without the use of sound measurement techniques or adequate definitions of the construct. The end result, of course, is a reliance on face validity. Rasch measurement provides a much needed solution to scaling the dispositions needed for good teaching when a credible construct is operationally used and visibly defined. This paper presents early work in the development of five related instruments measuring ten standards-based principles related to dispositions. The instruments use different item structures and response formats, which are aggregated into a single disposition scale that includes sub-scale scores for each of the principles.