Modelling the proportion of failed courses and GPA scores for engineering major students

There is special interest on the factors which may contribute for the best academic performance of undergraduate students. Particularly, in Brazil, because of the recent quota system and affirmative action programs implemented by some universities and the Federal Government, this issue has been of great interest. We use here zero-one inflated beta models with heteroscedasticity to model the proportion of failed courses taken by Engineering major students at the State University of Campinas, Brazil. We also model the grade point average score for those students with a heteroscedastic skew t distribution. The database consists of records of 3,549 students with Engineering major who entered in the University from 2000 to 2005. The entrance exam score in each subject, some academic variables and their socioeconomic status are considered as covariates in the models. A residual analysis based on randomized quantile residuals is performed as well. Finally, we believe that the results found in this study can be useful to improve the university polices for new students since it was possible to identify student profiles with respect to their academic performance.