Development of test instruments to measure students' mathematical problem-solving skills

Abstract

This study aims to develop a test instrument that can measure the ability to solve mathematical problems, focusing on the development procedures and the quality of the resulting instrument. The research method used is Research Development (research and development/R&D) with a development model based on the type of formative evaluation Tessmer, which involves the preliminary stage, self evaluation, prototyping (expert review, one to one, small group), and field tests. The test subjects in this study were 36 students of Class XI TKR Vocational High School. The test results showed that the mathematical problem solving test instruments have high validity, assessed based on the Coefficient Validity Ratio (CVR) of 1, and meet the criteria with the value of the Coefficient Validity Index (CVI) of 1, which is in the very appropriate category (0.68-1.00). In addition, this test instrument is also considered reliable with a value of 0.732, which is categorized as high and is in the range of 0.60<r11<0.80. The difficulty level of the test questions is categorized as good, with 60% of the questions having a good difficulty level and an average difficulty level of 0.58, which is in the medium category (0.31-0.70). The distinguishing power of the test instrument was considered good, with 93.34% of the questions meeting the criteria for distinguishing power, and the average distinguishing power of 0.35, categorized as sufficient (Dp>0.2). Thus, this student math problem solving test instrument can be considered to be of good quality based on the results of the tests carried out.