The fifth online academic seminar of the Spring Semester of 2020-2021 will be given by Dr. İbrahim Burak Ölmez. The title of his talk is "Coordinating Psychometric Modeling with U.S. Mathematics Teachers' Reasoning About Fraction Arithmetic." The seminar will be held in English.

This presentation will focus on part of my dissertation research. I will report responses of a nationwide sample of 990 in-service U.S. middle grades mathematics teachers to a novel survey that measured reasoning about fraction arithmetic. The survey focused on four components of reasoning about fraction arithmetic in terms of measured quantities: Referent units, Reversibility, Partitioning and iterating, and Appropriateness. I analyzed item responses using the mixture Rasch model and detected 3 latent classes, each with its own characteristic pattern of strengths and weaknesses. To understand what distinguished the performance of teachers in the three classes, I analyzed their responses to each item. One main result is that the three classes were clearly distinguished on items targeting Reversibility and Partitioning and iterating than it was on items targeting Referent units and Appropriateness. A second main result is the formation of a nested structure in the components of reasoning on which the teachers performed well. The results extend recent advances in measuring the mathematical knowledge of teachers.

Please click to link for the event.