The research aims to determine the factors affecting PISA 2018 reading skills using the Random Forest and MARS methods and to compare their prediction abilities. This study used the information from 5713 students, 2838 (49.7%) male and 2875 (50.3%) female, in the PISA 2018 Turkey. The analysis shows the MARS method performed better than the Random Forest method. In both methods, the most significant factor affecting reading skills in Turkey is "the number of books in the house." The variables the MARS method finds significant are "students' perception of difficulty, motivation for reading skills, father's educational status, reading pleasure, bullying experience of the student, mother's educational status, attitude towards school, classical artifacts at home, supplementary school books at home, competition at school, competitive power, cooperation perception at school, reading frequency, self-efficacy, poetry books at home, anxiety about reading skills, and teacher support." However, the other variables had no relationship to prediction. This study is expected to serve as a model for the use of data mining in educational research.