The document summarizes research on classifying breast cancer datasets using decision trees. The researchers used a Wisconsin breast cancer dataset containing 699 instances with 10 attributes plus a class attribute. They preprocessed the data to handle missing values, compared various classification methods, and achieved the best accuracy of 97% using decision trees with attribute selection. Issues addressed included unbalanced classes and future work proposed methods like clustering and multiple classifiers to further improve accuracy.

1. Classification of Breast Cancer dataset using Decision Tree Induction Sunil Nair Abel Gebreyesus Masters of Health Informatics Dalhousie University HINF6210 Project Presentation – November 25, 2008

11. Comparison chart – Handle Missing Value Confusion Matrix Total Correctly Classified Instances Test split = 223 Accuracy Rate: 95.78% How many predictions by chance? Expected Accuracy Rate = Kappa Statistic - is used to measure the agreement between predicted and actual categorization of data while correcting for prediction that occurs by chance. 89% 95% 7% 14 Missing Replaced 90% 96% 5% 11 Missing Removed 87% 94% 8% 14 Complete Exp. Acc. Rate Act. Acc. Rate MAE # RULES DATASET PERFORMANCE EVALUATION 233 70 163 Total 66 63 3 M 167 7 160 B Total M B Class

14. Classification Methods Comparison 94% 97% 3% 233 Support Vector M 92% 97% 4% 233 DT-J48 79% 91% 10% 233 Neural Network 90% 96% 4% 233 Naïve Bayes Exp. Acc. Rate Act. Acc. Rate MAE # Total Inst. CLASSIFIER PERFORMANCE EVALUATION Test Set

16. Attributes Selected – most IG weka.filters.supervised.attribute.AttributeSelection-Eweka.attributeSelection.InfoGainAttributeEval-Sweka.attributeSelection.Ranker 89% 95% 7% 14 Missing Replaced 90% 96% 5% 11 Missing Removed 92% 97% 4% 11 Attributes Selected Exp. Acc. Rate Act. Acc. Rate MAE # RULES DATASET PERFORMANCE EVALUATION 0.198 Mitosis 9 0.443 Marginal Adhesion 8 0.459 Clump Thickness 7 0.466 Normal Nucleoli 6 0.505 Single Epithelial Cell Size 5 0.543 Bland Chromatin 4 0.564 Bare Nucleoli 3 0.66 Uniformity of Cell Shape 2 0.675 Uniformity of Cell Size 1 Information Gain Attribute Rank

17. The DT – IG/Attribute selection Visualization

21. Stratified Sampling Method

22. Performance Evaluation 92% 96% 3% 13 412 Testing set 97% 99% 2% 13 476 Training set Exp. Acc. Rate Act. Acc. Rate MAE # Rules # Instances Dataset PERFORMANCE EVALUATION Test Set

23. Tree Visualization

27. Questions / Comments Thank You !