Iterative Identification of Fault-Prone Binaries Using In-Process Metrics

gunnarku — Mon, 15 Sep 2008 16:19:00 GMT

Interestingly enough yet another research paper on what I've worked on has been accepted to a software engineering conference. Lucas Layman, Nachi Nagappan, and I will be at ESEM 2008 presenting on 10/10/2008 the results of our work.

Here's the summary:

Code churn, the amount of code change taking place within a software unit over time, has been correlated with fault-proneness in software systems. We investigate the use of code churn and static metrics collected at regular time intervals during the development cycle to predict faults in an iterative, in-process manner. We collected 159 churn and structure metrics from six, four-month snapshots of a 1 million LOC Microsoft product. The number of software faults fixed during each period is recorded per binary module. Using stepwise logistic regression, we create a prediction model to identify fault-prone binaries using three parameters: code churn (the number of new and changed blocks); class Fan In and class Fan Out (normalized by lines of code). The iteratively-built model is 80.0% accurate at predicting fault-prone and non-fault-prone binaries. These fault-prediction models have the advantage of allowing the engineers to observe how their fault-prediction profile evolves over time.

See you in Kaiserslautern, Germany.

Assessing the Relationship between Software Assertions and Code Quality

gunnarku — Wed, 14 Jun 2006 04:08:00 GMT

After almost a year of writing code, verifying the results, fixing various review comments, and doing a number of other things we finally published our paper about the relationship between assertions and code quality. Here's the summary:

The use of assertions in software development is thought to help produce quality software. Unfortunately, there is scant empirical evidence in commercial software systems for this argument to date. This paper presents an empirical case study of two commercial software components at Microsoft Corporation. The developers of these components systematically employed assertions, which allowed us to investigate the relationship between software assertions and code quality. We also compare the efficacy of assertions against that of popular bug finding techniques like source code static analysis tools. We observe from our case study that with an increase in the assertion density in a file there is a statistically significant decrease in fault density. Further, the usage of software assertions in these components found a large percentage of the faults in the bug database.

Any feedback from interested parties is welcome ;-)

Gunnar Kudrjavets

Iterative Identification of Fault-Prone Binaries Using In-Process Metrics

Assessing the Relationship between Software Assertions and Code Quality