Problem-Solving Skills on Night Sky Brightness and Light Pollution: A Rasch Analysis

Abstract

Light pollution was a global environmental problem that disrupted ecosystems, particularly in the field of astronomy. One of the main indicators of light pollution was the increased brightness of the night sky. This phenomenon was highly relevant to physics education, particularly in Earth and Space Physics courses. However, studies measuring problem-solving skills in the context of real-world scientific phenomena, such as night sky brightness as an indicator of light pollution, were still very limited. Therefore, this study aimed to test the feasibility of a problem-solving skills assessment tool and obtain an overview of students' problem-solving skills in solving problems related to light pollution issues, using night sky brightness as an indicator. This study used a quantitative descriptive design and involved 75 physics education students. The instrument consisted of one main question containing four stages of problem-solving skills. Thus, there were four items analyzed using the Rasch Model. The analysis results showed that the instrument met the assumption of unidimensionality with a very good category. Reliability, reviewed from three aspects: person reliability, item reliability, and Cronbach's Alpha, was categorized as weak, excellent, and sufficient, respectively. All items were deemed appropriate (fit), with the difficulty level consisting of one easy item, two medium items, and one difficult item. All items had excellent discriminatory power. The use of this instrument indicated that, overall, students' problem-solving skills were excellent. This finding indicated that the instrument was suitable for obtaining an overview of students' problem-solving skills. This study implied that the developed instrument could be used in learning to provide an overview of students’ problem-solving skills, particularly in the context of light pollution issues.