PSYCHOMETRIC EVALUATION OF MATHEMATICAL PROBLEM-SOLVING ABILITY AND MATHEMATICAL BELIEFS INSTRUMENTS FOR STATISTICS LEARNING

Purpose – This study examined the psychometric properties of a mathematical problem-solving ability test and a mathematical beliefs questionnaire developed for statistics learning at the junior secondary school level.Methodology – This study adopted a quantitative descriptive research design involving 32 eighth-grade students from a public junior secondary school in Yogyakarta, Indonesia. Two instruments were employed: a mathematical problem-solving ability test and a mathematical beliefs questionnaire. The psychometric quality of the instruments was evaluated within the Classical Test Theory (CTT) framework through analyses of item validity, internal consistency reliability, item difficulty, and discrimination indices to examine both overall measurement consistency and individual item functioning. All analyses were performed using AnBuso 8.0, ITEMAN 4.3, and Microsoft Excel.Findings – The findings revealed that the mathematical problem-solving ability test demonstrated good item discrimination, moderate difficulty levels, and high reliability, indicating that the instrument provides consistent and dependable measurements. The mathematical beliefs questionnaire also exhibited excellent internal consistency, demonstrating its suitability for measuring students' mathematical beliefs. Overall, the evaluation demonstrates that the developed instruments possess adequate psychometric quality, supporting their use for measuring students' mathematical problem-solving ability and mathematical beliefs in statistics learning.Contribution – This study contributes to mathematics education by providing empirically validated assessment instruments that support more accurate classroom assessment and may serve as references for teachers and researchers in developing, evaluating, and implementing similar instruments in other educational contexts.