PSM7 and PSM8: Validating Two Problem-solving Measures.

New mathematics standards were adopted broadly across the United States of America between 2011-2013. Problem solving is a central facet of these new standards. Given new standards and the prominence of mathematical problem solving, there is a need for valid and reliable assessments that measure students' abilities related to those standards. Moreover, Rasch measurement techniques support psychometric analyses during validation studies, effectively measuring students' and items' properties in ways not afforded by true score theory. This manuscript builds upon past research (see Bostic and Sondergeld, 2015a, 2015b) with a validity study of two related problem-solving measures for grades seven and eight. Results from this validation study indicated that the problem-solving measures for grades seven and eight had sufficient evidence for their use.

An experimental study using Rasch analysis to compare absolute magnitude estimation and categorical rating scaling as applied in survey research.

Limited research has applied a measurement model to compare the rating scale functioning of categorical rating scaling (CRS) and absolute magnitude estimation scaling (MES) when rating subjective stimuli. We used an experimental design and applied the Rasch model to the survey data, with each respondent rating items using MES and one of four commonly used agreement-disagreement rating scales. The results indicated that the CRS and MES data were comparable in person and item separation and reliability when the respondents' scales were known. MES had lower standard error for people and items; however MES had disordered step calibrations. Finally, the respondents reported preference of CRS to MES.