How Domain Knowledge Accumulation Influences Software Defects: An Empirical Analysis

Understanding the trend of software defect density at the time of delivery has significant implications for organizations or agencies to make long-term risk control strategies. Software development is a knowledge-intensive activity. Organizations and software developers are expected to reduce defects rates with the accumulation of knowledge and experience, however, they are constantly confronted with challenges imposed by new projects. This paper investigates the compound effects of knowledge experience and new projects on software defects. The study performs an empirical analysis on 60 software systems developed by 8 organizations in the Chinese aviation industry from year 2007 to 2014. The results show that the density of severe defects obviously reduces over time, but no consistent trend is observed for defects of low severity. Moreover, the density of high severity defects acutely increases in newly developed projects. This reveals that enhanced strategies should be employed to reduce severe defects in new software projects, in addition to the current practices of software process improvement.