Estimation and Improvement of Software Quality using Time Series Data from Software Development Process

在本研究中，我们试图为软件开发开发开发一种强调实用性，特别是便于在实际开发领域实现的质量评估方法。为此，我们考虑了以下三个观点：使用从软件开发的设计和编码阶段收集的度量数据来预测软件质量。提出了一种利用设计和编码阶段检测缺陷的时间序列数据预测产品最终质量的方法。更详细地说，我们根据缺陷检测的趋势将所有项目分为4组。然后，我们分析了类的最终质量。使用主观数据预测软件质量，如开发计划的有效性和软件开发计划与实际进度之间的差异。在这里，为了提高预测的准确性，我们在项目开始时引入了额外的数据，即关于软件风险的主观问卷。我们认为软件风险与产品的最终质量密切相关。我们利用贝叶斯信念网络建立了风险与最终质量之间的关系模型。最后，我们尝试对软件开发的各个阶段进行软件风险的模拟，并对软件产品的质量进行估计。为此，我们开发了一个系统，在开发的每个阶段使用贝叶斯分类器来估计软件质量。利用该方法，可以实现对软件质量的实际评估。

In this research, we tried to develop a quality estimation method for software development which emphasizes on practical use, especially, ease for the implementation in the actual development field. To do so, we consider the following three viewpoints :1.Prediction of software quality suing the metrics data collected from the design and coding phases in the software development.We proposed a method to predict final quality of products using time series data of detected defects in design and coding phases. In more detail, we classified all projects into 4 groups according to the trend of defects detection. We then analyzed resultant quality of the classes.2. Prediction of software quality using subjective data such as validity of development plan and difference between planned and actual progress of software development.Here, in order to improve the accuracy of prediction, we introduced additional data, subjective questionnaire about software risks at the beginning of project. We considered that the software risks deeply related to the final quality of product. We modeled the relationship among risks and final quality using Bayesian belief network.3. Method to improve quality using simulation techniqueFinally we tried to simulate the software risk and to estimate quality of software products for each phase of software development. To do so, we developed a system to estimate software quality using Bayesian classifier at each phase of development. By using this method, practical estimation of software quality can be achieved.