Bogus Bugs, Duplicates, and Revealing Comments: Data Quality Issues in NPR

The performance of a machine learning system is not only determined by the model but also, to a substantial degree, by the data it is trained on. With the increasing use of machine learning, issues related to data quality have become a concern also in automated program repair research. In this position paper, we report some of the data-related issues we have come across when working with several large APR datasets and benchmarks, including, for instance, duplicates or "bogus bugs". We briefly discuss the potential impact of these problems on repair performance and propose possible remedies. We believe that more data-focused approaches could improve the performance and robustness of current and future APR systems.