1. How Significant Is the Effect of Faults Interaction on Coverage Based Fault Localizations? Xiaozhen Xue Advanced Empirical Software Testing Group Department of Computer Science Texas Tech University 10.1.2013

2. Outline Introduction Research Questions Experimental procedure Data analysis Discussion Conclusion

3. Introduction Software testing is an important process in software life cycle. Fault localization is a major activity in software testing. Fault localization is time consuming and expensive.

4. Introduction Coverage based fault localization

5. Introduction example

6. Introduction Coverage based fault localization techniques is effect when single fault in presence. It is a common belief that the coverage based fault localization techniques are less effective in the presence of multiple faults.

7. Introduction Motivation: Empirically investigate the effectiveness of Coverage Based Faults Localization when multiple faults exist in the program.

8. Research Questions RQ1: How prevalent is the fault interferences phenomenon in the object-oriented programming languages such as Java? RQ2: How significant is the influence of fault interactions on debugging cost? RQ3: Do the frequencies of fault interferences vary for different ranking metrics? RQ4: How different is the frequency of observing fault interference instances for various number of faults? RQ5: How different is the frequency of observing fault interference instances for various type of faults?

9. Experimental procedure Subjects programs

10. Experimental procedure Multiple faults

11. Experimental procedure metrics

12. Experimental procedure Metrics proposed in our previous work

13. Data Analysis Data visualization

14. Data Analysis The significance of faults interactions

15. Data Analysis The significance of faults interactions

16. Data Analysis The significance of faults interactions

17. Data Analysis The significance of faults interactions

18. Discussion The prevalence of faults interference

19. Discussion The prevalence of faults interference

20. Data Analysis The roles of ranking metrics

21. Conclusion The coverage-based fault localization techniques are still effective in localizing faults in the presence of multiple faults. The effect of fault interactions on debugging cost is negligible and statistically insignificant. The frequency of observing fault interference instances differ for various ranking metrics.

22. Thank you!!