Analysis of Science Literacy and Critical Thinking Skills Questions on Ecology and Biodiversity Material Using the Rasch Model Azrul Laila, Kadek Dwi Hendratma Gunawan, Riezky Maya Probosari, Daru Wahyuningsih
Department of Science Education, Faculty of Teacher Training and Education, Sebelas Maret Universitiy, Surakarta, Indonesia
Scientific literacy and critical thinking skills are interrelated and essential in enhancing students^ cognitive abilities. Many students still face challenges in applying deep thinking to solve problems, emphasizing the need for valid assessment instruments. This study aims to analyze test instruments measuring scientific literacy and critical thinking skills using the Rasch model. The research was conducted on Grade VIII students at SMP Negeri 2 Surakarta, focusing on ecology and biodiversity. A descriptive quantitative method with random sampling was applied, and data were analyzed using Winsteps software. The scientific literacy test showed a person reliability of 0.68 (moderate) and an item reliability of 0.82 (good), while the critical thinking test had a person reliability of 0.63 (low) and an item reliability of 0.84 (good). Unidimensionality results indicated that the raw variance explained by measures was 41.2% for the critical thinking test (good) and 36.0% for the scientific literacy test (acceptable). Item fit analysis showed that one item in the critical thinking test and three items in the scientific literacy test did not meet the fit criteria. The DIF analysis revealed no gender bias in either test. Item difficulties ranged from very difficult to very easy. Person measure analysis identified two students with the highest ability scores, and 88% of students matched the Rasch model based on person fit analysis. These results support the effectiveness of the Rasch model in identifying item quality and improving the validity of instruments in science education.