This article analyses the tests results evaluating the knowledge of students of basic mathematics courses at the University of Economics and the University of Finance and Administration in Prague. The relationship between the knowledge of definitions and the ability to solve exercises is tested. This article focuses on the theoretical part by assessing the ability to formulate the definitions and to analyse the relationships between the study of the theory, the ability to formulate definitions and to solve exercises. For this purpose the statistical evaluation utilizing the log-linear models is used. The most common errors in the theoretical part are presented.