Investigating Teachers Competencies in Using Assessment Tools Through the Many-Facet Rasch Model

The purpose of this study is to analyze teachers’ perceived competencies in using various assessment tools through the Many-Facet Rasch Model (MFRM). The study, designed as a quantitative survey, included 37 volunteer teachers working in middle schools and high schools in Türkiye during the 2025–2026 academic year. Data were collected using six assessment tools: self-assessment, peer assessment, performance task, rubric, digital tools, and portfolio, along with seven competency criteria related to the use of these tools. The research design, in which the rater, assessment tool, and assessment-criterion facets were crossed, was analyzed using FACETS 4.3.1. The results indicated that the core assumptions of the Rasch model were satisfied and that model-data fit was high, supporting the comparability of the obtained measures. Findings showed that teachers’ perceived competencies vary by assessment tool. Teachers perceived themselves as less competent in self-assessment and performance tasks, and these tools were positioned at higher difficulty levels. In contrast, a higher level of perceived competence was observed in portfolio use. The high separation index obtained for the rater facet indicates pronounced individual differences among teachers in terms of perceived competence. Regarding the assessment criteria, design-oriented areas, such as preparing content, integrating with learning outcomes, and aligning the tool with existing learning outcomes and content, were found to be more challenging. By contrast, teachers perceived themselves as more competent in implementation and in sustaining student motivation. The findings suggest that summarizing teacher competencies with a single mean score is not sufficient. The MFRM approach, which jointly considers tool, criterion, and rater variables, can reveal differentiated competency areas more clearly. Accordingly, professional development programs should be structured based on priorities identified at the tool and criterion levels.