Countries participate in common tests to compare their positions with other countries and monitor their progress. While conducting these tests, comparing the achievement or attitudes between these countries or individuals without considering the differences between them will result in biased results. The anchoring vignette method was used in PISA 2012 as an alternative to eliminate this bias. In this study, the responses of Turkish, Bulgarian, and Greek students' to the survey questions in PISA 2012 about their mathematics teachers' class management and adjusted response categories based on their responses to anchoring vignettes were analyzed, and whether countries differ in class management or not was investigated. The data collected from 4,895 people were analyzed (1,665 from Bulgaria, 1,662 from Greece, and 1,568 from Turkey). All responses were not used; only three anchoring vignettes in the CLSMAN questionnaire and the 3rd item of the original questionnaire were used. The analyzes were performed in the R program with the ancors package. As a result of the research, it was found in both calculations that Greek teachers are quite flexible in starting class on time, and there is a significant difference between the response categories of other countries. According to the self-assessment responses, there is no difference between Turkish and Bulgarian teachers' class management; however, there is a significant difference between them according to the adjusted response. Different methods can be used in the process of evaluating anchoring vignettes using a non-parametric approach. Weighting is different in these methods. A single method can be used regarding the feature to be investigated or the researcher's algorithm preference; or as in this study, all the four methods can be used, and the comparisons can be interpreted.