Our tool scores each file against a given defect description and then ranks the files in descending order of score, aiming for at least one of the files affected by the defect to be among the top-ranked ones, so that it can serve as an entry point to navigate the code and find the other affected files. In particular it succeeds in placing an affected file among the top-1, top-5 and top-10 files for 48%, 70% and 77% of CRs, on average.
We compared our approach to five other state-of-the-art tools, using their own five metrics on their own six case studies. Out of the 30 performance indicators, we match 2 and improve 28. On average, for 77% of the bug reports we place one or more affected files in the top-10 ranked files.
We also improved, in most cases substantially, the mean reciprocal rank value for all six applications evaluated, thereby reducing the number of files to inspect before finding a relevant file.
The results for our study can be obtained by clicking here: results