International Journal of Evaluation and Research in Education (IJERE) Vol. 12, No. 4, December 2023, pp. 1771~1780 ISSN: 2252-8822, DOI: 10.11591/ijere.v12i4.25790  1771 Journal homepage: http://ijere.iaescore.com Indonesian emotion regulation scale for students based on reappraisal and suppression factor: The Rasch analysis Waharjani 1 , Wahyu Nanda Eka Saputra 2 , Dewi Afra Khairunnisa 2 1 Department of Hadith Science, Faculty of Islamic Religion, Universitas Ahmad Dahlan, Yogyakarta, Indonesia 2 Department of Guidance and Counseling, Faculty of Teacher Training and Education, Universitas Ahmad Dahlan, Yogyakarta, Indonesia Article Info ABSTRACT Article history: Received Oct 25, 2022 Revised Aug 31, 2023 Accepted Sep 11, 2023 Every human being has emotional turmoil, which will be a serious problem if they cannot control it. The importance of emotion regulation has become one of the bases for developing a measure of emotion regulation for students, the Indonesian emotion regulation scale (IERS). No research yet describes an instrument that measures students’ level of emotion regulation in Indonesia. IERS consists of nine items in two aspects: reappraisal and suppression factor. The content validity test involves two experts in the field of psychometrics. In comparison, the construct validity test involved 354 high school students in Yogyakarta, Indonesia. Data analysis using inter- rater reliability (IRR) coefficient of Cohen’s kappa and Rasch analysis. Based on the study of the IRR coefficient of Cohen’s kappa, two experts agree on the acceptability of the IERS statement items. Besides that, the results of the application of Rasch analysis show that IERS is good, precise, and conforms with the model. IERS is a reliable and valid tool to measure students’ level of emotion regulation accurately. This paper discusses the implications and recommendations for further research for the implementation of guidance and counseling containing the value of emotion regulation as a follow-up to the performance of IERS. Keywords: Aggressiveness Bullying Emotion dysregulation Indonesian version scale Violence This is an open access article under the CC BY-SA license. Corresponding Author: Wahyu Nanda Eka Saputra Department of Guidance and Counseling, Faculty of Teacher Training and Education, Universitas Ahmad Dahlan Banguntapan, Bantul, Yogyakarta 55166, Indonesia Email: wahyu.saputra@bk.uad.ac.id 1. INTRODUCTION Students need a safe and comfortable situation to study at school. Several research results indicate that the level of feeling safe and comfortable at school correlates with student performance in the academic field [1], [2]. Various feelings of discomfort, insecurity and even fear of students in academic activities at school appear due to high student violence [3], [4]. The school situation is one of the essential factors that can support achieving educational goals. However, the reality on the ground shows different dynamics. Student violence is a problem that often arises in schools, for example, aggressive behavior [5], [6] and bullying [7], [8], both traditional and online. One of the causes of students causing violence is the inability of students to optimize emotion regulation [9], [10]. This absence of emotion regulation triggers the lack of students' efforts to suppress the violent impulses that exist in them. A measuring tool to identify the level of emotion regulation is one of the options for determining student emotion regulation portraits. The measurement results with these measuring instruments are the basis for preparing guidance and counseling programs to improve emotion regulation [11], [12]. Several studies