“…Lines of code (LOC) is a commonly used size metric for defect prediction (Akiyama, 1971) while McCabe (1976) and Halstead (1977) are the mostly used complexity metrics. Many works have been done to find the correlation of software metrics and defectproneness by building different predictive models including discriminant analysis (Khoshgoftaar, Allen, Kalaichelvan, & Goel, 1996;Munson & Khoshgoftaar, 1992), logistic regression (Basili, Briand, & Melo, 1996;Gyimothy, Ferenc, & Siket, 2005;Zhou & Leung, 2006), factor analysis , fuzzy classification (Ebert, 1996), classification trees (Gokhale & Lyu, 1997;Gyimothy et al, 2005;Koru & Liu, 2005;Menzies et al, 2007), Bayesian network (Pai & Dugan, 2007;Zhou & Leung, 2006), artificial neural networks (ANN) (Gondra, 2008;Gyimothy et al, 2005;Kanmani, Uthariaraj, Sankaranarayanan, & Thambidurai, 2007;Khoshgoftaar, Lanning, & Pandya, 1994;Khoshgoftaar, Allen, Hudepohl, & Aud, 1997;Neumann, 2002;Quah & Thet Thwin, 2004) support vector machines (Gondra, 2008;Xing, Guo, & Lyu, 2005), etc. Since the relationship between software metrics and defect-proneness of software modules are often complicated and nonlinear, machine learning methods such as neural networks have been shown more adequate for the problem than traditional linear models (Khoshgoftaar et al, 1994(Khoshgoftaar et al, , 1997 AdaBoost -an adaptive boosting algorithm (Freund, 1995;Freund & Schapire, 1997), which has shown to be an effective ensemble learning method to significantly improve the performance of neural network classifiers (Schwenk & Bengio, 2000).…”