Improving the Accuracy of Vulnerability Report Classification Using Term Frequency-Inverse Gravity Moment

Software vulnerability analysis is one of the critical issues in the software industry, and vulnerability classification plays a major role in this analysis. A typical vulnerability classification model usually involves a stage of term selection, in which the relevant terms are identified via feature selection. It also involves a stage of term weighting, in which document weights for the selected terms are computed, and a stage for classifier learning. Generally, the term frequency-inverse document frequency (TF-IDF) is the most widely used term-weighting method. However, empirical evidence shows that the TF-IDF is plagued with issues pertaining to its effectiveness. This paper introduces a new approach for vulnerability classification, which is based on term frequency and inverse gravity moment (TF-IGM). The proposed method is validated by empirical experiments using three machine learning algorithms on ten publicly available vulnerability datasets. The result shows that TF-IGM outperforms the benchmark method across the applications studied.