Measuring the Efficacy of Code Clone Information in a Bug Localization Task: An Empirical Study

Much recent research effort has been devoted to designing efficient code clone detection techniques and tools. However, there has been little human-based empirical study of developers as they use the outputs of those tools while performing maintenance tasks. This paper describes a study that investigates the usefulness of code clone information for performing a bug localization task. In this study 43 graduate students were observed while identifying defects in both cloned and non-cloned portions of code. The goal of the study was to understand how those developers used clone information to perform this task. The results of this study showed that participants who first identified a defect then used it to look for clones of the defect were more effective than participants who used the clone information before finding any defects. The results also show a relationship between the perceived efficacy of the clone information and effectiveness in finding defects. Finally, the results show that participants who had industrial experience were more effective in identifying defects than those without industrial experience.