A Review of Models for Evaluating Quality in Open Source Software <s> Introduction <s> Recently, many software visualization (SV) techniques and tools have become available to developers in order to help them understand their software. In our project, firstly, we identified a list of SV tools that we described, and evaluated qualitatively using the taxonomy of Price et al. Our experience with this taxonomy as well as the impact of the qualitative evaluation on Bell Canada will be discussed in this paper. Then, a quantitative evaluation was conducted in spring 2000 with more than 100 participants. In this paper, we especially put the emphases on the perspectives of the results, by reporting on our experiences and by discussing the major findings and their impact. <s> BIB001 </s> A Review of Models for Evaluating Quality in Open Source Software <s> Introduction <s> Open Source Software (OSS) development and use has increased significantly over recent years. Therefore, there is a need to analyze and understand these projects. Software quality is an important characteristic effecting overall system lifecycle cost, performance and useful life. The existing models for software quality are based on empirical analysis of propriety source software (PSS), and need to be verified in OSS. Research on PSS has revealed that software quality declines, as it ages. Part of this decline is associated with the lifecycle maintenance activities that introduce change in the size and complexity of the system, while introducing software errors into modified system. Lifecycle maintenance activities in OSS systems are processed under a very different paradigm. We are interested in investigating the effects of maintenance activities on OSS project outcomes. Linux is one of the most popular and complex OSS project available. In our research, we investigate the characteristics of Linux source code. In this position paper we present some preliminary results of the effects of various types of maintenance activities on quality of Linux software. <s> BIB002
Open source software is all around us today. They range from operating systems (such as Linux, Solaris, FreeBSD) to middleware/database technologies (such as Apache web server/MySQL) and then to end-user products such as web browsers (e.g. Mozilla Firefox). The list is in exhaustive. Most open source software projects are regarded to be of high quality from the perspectives of designers, writers and even those who use the software BIB002 . The Institute of Electrical and Electronics Engineers (IEEE) defines quality as, "the degree to which a system, component or process meets specified requirements" or "the degree to which a system, component or process meets customer or user needs or expectations"  . In order to measure quality in software, quality models can be used. The quality model approach is one of two main approaches for understanding the quality of software products  . Some quality models focus around a set of attributes/metrics used to distinctively assess quality by making quality a quantifiable concept. Example is the McCall model (McCall et al., 1977) , the Boehm model BIB001 (Boehm, et al., 1978) , and the ISO9126 product quality standard (ISO, 2001) . Due to the fact that these quality models ignored some attributes (such as community) unique to open source software, new quality models began to emerge in 2003  specific to open source software. The aim of this paper therefore is to identify the characteristic features, unique strengths and limitations of existing open source software quality models. This can serve as a guide to those intending to use any of the models and also to lay a foundation for improvements on the models. The rest of this paper is organized as follows. Section 2 presents the research method that was applied. Section 3 presents the characteristic features, unique strengths and limitations of existing open source quality models. Section 4 is a comparative study of the models based on selected criteria. Section 5 discusses the comparison made and Section 6 concludes the paper.