  The performance of fault localization techniques is critical to their
adoption in practice. This paper reports on an empirical study of a wide range
of fault localization techniques on real-world faults. Different from previous
studies, this paper (1) considers a wide range of techniques from different
families, (2) combines different techniques, and (3) considers the execution
time of different techniques. Our results reveal that a combined technique
significantly outperforms any individual technique (200% increase in faults
localized in Top 1), suggesting that combination may be a desirable way to
apply fault localization techniques and that future techniques should also be
evaluated in the combined setting. Our implementation is publicly available for
evaluating and combining fault localization techniques.
