Abstract
Hierarchical models are highly useful tools for clustered and multilevel type of data and coefficients can vary by clusters in these models. In this study, several types of two-level random intercept model specifications are used to compare the mathematics scores of 8th grade students from three different safe and orderly levels of schools, after taking into account of variation both between classes and between students within the same class. The data obtained from Trends in International Mathematics and Science Study (TIMSS) 2011, released shortly, which is a large-scale international database and it shows trends in mathematics and science achievements at both 4th and 8th grades. Class size and weekly spent time on mathematics homework are emphasized in school and student levels, respectively. This study is conducted for Turkey, but it can easily be replicated for other countries enrolled TIMSS.