Ninth Grade Student’ Self-assessment in Science: A Rasch Analysis Approach

Based on the competency indicators of the nine-year compulsory curriculum in Taiwan, this study constructed a self-assessment scale suitable for use by junior high school students to evaluate their comprehension of science-related concepts. Using random strata sampling this study surveyed ninth grade students in Taiwan in 2012. A total of 1,326 questionnaires were distributed and 1,005 valid questionnaires were recovered. The Rasch model was employed to study the self-assessment results and analyze difficulties in learning science-related concepts as well as discrimination, reliability, validity, suitability, and data error detection. The three conclusions of this study are as follows: 1) Diagnostic tests for teaching evaluation should be based on Rasch measurement results. 2) A structure for diagnosing the item response of students should be constructed to replace conventional test analysis and to build a framework for diagnosing the response of students to test items. 3) The actual capabilities of students must be considered in the development and selection of teaching activities.