%0 Conference Paper %B Proceedings of the 2008 international workshop on Mining software repositories - MSR '08 %D 2008 %T On the relation of refactorings and software defect prediction %A Sigmund, Thomas %A Gall, Harald C. %A Ratzinger, Jacek %Y Hassan, Ahmed E. %Y Lanza, Michele %Y Godfrey, Michael W. %K argouml %K bug fixing %K bug reports %K defects %K evolution %K jboss %K liferay %K prediction %K refactoring %K spring %K weka %K xdoclet %X This paper analyzes the influence of evolution activities such as refactoring on software defects. In a case study of five open source projects we used attributes of software evolution to predict defects in time periods of six months. We use versioning and issue tracking systems to extract 110 data mining features, which are separated into refactoring and non-refactoring related features. These features are used as input into classification algorithms that create prediction models for software defects. We found out that refactoring related features as well as non-refactoring related features lead to high quality prediction models. Additionally, we discovered that refactorings and defects have an inverse correlation: The number of software defects decreases, if the number of refactorings increased in the preceding time period. As a result, refactoring should be a significant part of both bug fixes and other evolutionary changes to reduce software defects. %B Proceedings of the 2008 international workshop on Mining software repositories - MSR '08 %I ACM Press %C New York, New York, USA %P 35-38 %8 05/2008 %@ 9781605580241 %! MSR '08 %R 10.1145/1370750.1370759 %> https://flosshub.org/sites/flosshub.org/files/p35-ratzinger.pdf %0 Conference Paper %B Proceedings of the 2005 international workshop on Mining software repositories %D 2005 %T Mining evolution data of a product family %A Fischer, Michael %A Oberleitner, Johann %A Ratzinger, Jacek %A Gall, Harald %K bsd %K change analysis %K change history %K cvs %K evolution %K freebsd %K netbsd %K openbsd %K release history %K source code %K text mining %X Diversification of software assets through changing requirements impose a constant challenge on the developers and maintainers of large software systems. Recent research has addressed the mining for data in software repositories of single products ranging from fine- to coarse grained analyses. But so far, little attention has been payed to mining data about the evolution of product families. In this work, we study the evolution and commonalities of three variants of the BSD (Berkeley Software Distribution), a large open source operating system. The research questions we tackle are concerned with how to generate high level views of the system discovering and indicating evolutionary highlights. To process the large amount of data, we extended our previously developed approach for storing release history information to support the analysis of product families. In a case study we apply our approach on data from three different code repositories representing about 8.5GB of data and 10 years of active development. %B Proceedings of the 2005 international workshop on Mining software repositories %S MSR '05 %I ACM %C New York, NY, USA %P 12-16 %@ 1-59593-123-6 %U http://doi.acm.org/10.1145/1082983.1083145 %R http://doi.acm.org/10.1145/1082983.1083145 %> https://flosshub.org/sites/flosshub.org/files/12MiningEvolution.pdf