This study aims to identify the sources of Differential Item Functioning (DIF) using the Mixture Ordinal Logistic Regression (Mixture OLR) method. a contemporary approach for detecting DIF. To analyze mathematics self-efficacy. data from a scale comprising 9 items were obtained from 5000 8th-grade students as part of the ABIDE-2016 project. https://cosmeticssquadets.shop/product-category/cap/