The mammographic mass dataset, which was used in this research, is obtained from the Mammographic Mass Database available in the UCI Machine Learning Repository [27]. This dataset contains mammographic information of breast cancer clinical instances, contributed by the Institute of Radiology of the University Erlangen-Nuremberg in Germany. Full-field digital mammography was used to collect the clinical instances for the dataset periodically from 2003 to 2006, resulting in a constantly increasing dataset size.