Abstract: Agile methods are a collection of different techniques and practices that share the same values and basic principles. Agile Software Development Quality Assurance provides in-depth coverage of the most important concepts, issues, trends, and technologies in agile software. This Premier Reference Source presents the research and instruction used to develop and implement software quickly, in small iteration cycles, and in close cooperation with the customer in an adaptive way. It is a comprehensive guide that helps researchers and practitioners in the agile software development process avoid risks and project failures that are frequently encountered in traditional software projects.

Abstract: In this paper, pair programming is empirically investigated from the perspective of developer personalities and temperaments and how they affect pair effectiveness. A controlled experiment was conducted to investigate the impact of developer personalities and temperaments on communication, pair performance and pair viability-collaboration. The experiment involved 70 undergraduate students and the objective was to compare pairs of heterogeneous developer personalities and temperaments with pairs of homogeneous personalities and temperaments, in terms of pair effectiveness. Pair effectiveness is expressed in terms of pair performance, measured by communication, velocity, design correctness and passed acceptance tests, and pair collaboration-viability measured by developers� satisfaction, knowledge acquisition and participation. The results have shown that there is important difference between the two groups, indicating better communication, pair performance and pair collaboration-viability for the pairs with heterogeneous personalities and temperaments. In order to provide an objective assessment of the differences between the two groups of pairs, a number of statistical tests and stepwise Discriminant Analysis were used.

Abstract: In this paper we discuss our empirical study about the advantages and difficulties 15 Greek software companies experienced applying Extreme Programming (XP) as a holistic system in software development. Based on a generic XP system including feedback influences and using a cause-effect model including social-technical affecting factors, as our research tool, the study statistically evaluates the application of XP practices in the software companies being studied. Data were collected from 30 managers and developers, using the sample survey technique with questionnaires and interviews, in a time period of six months. Practices were analysed individually, using Descriptive Statistics (DS), and as a whole by building up different models using stepwise Discriminant Analysis (DA). The results have shown that companies, facing various problems with common code ownership, on-site customer, 40�hour week and metaphor, prefer to develop their own tailored XP method and way of working-practices that met their requirements. Pair programming and test-driven development were found to be the most significant success factors. Interactions and hidden dependencies for the majority of the practices as well as communication and synergy between skilled personnel were found to be other significant success factors. The contribution of this preliminary research work is to provide some evidence that may assist companies in evaluating whether the XP system as a holistic framework would suit their current situation.

Abstract: This study is concerned with the formal assessment of a Distance Learning Environment (DLE) created to deliver a course on UML sequence diagrams to university-level students, divided into control and treatment groups. An ad-hoc DLE was constructed to deliver instruction to the treatment group, while the control group was taught in a traditional face-to-face way. The main point of concern is whether a DLE can be as effective for the treatment group, as the faceto- face lecture is for the control group, in terms of gaining mastery on the domain. So, a controlled experiment was organized and executed, in order to measure the participants� performance in both groups. The results have shown no statistically significant difference for both groups of students. So, it can be argued that in the context of this experiment and by following a DLE-design close enough to the traditional face-to-face approach, one can obtain equally good results using distance learning as with the traditional system. However, a number of concerns remain and more work is needed to generalize the results of this work on other domains.

Abstract: This chapter explores the management of the human resources that are involved in agile development. Because evidently human factors are critical for the success of agile methods, there is an urgent need for managing agile people effectively both at the corporate level and the project level. First part of the chapter proposes and discusses a model for personnel management based on the well-known People- CMM assessment and improvement model. In addition, the chapter proposes a model for allocating and rotating developers in pairs while pair programming. The model is based on the fact that different types of personalities and temperaments allow pairs that produce better quality results.

Abstract: This paper presents a controlled experiment study, investigating the impact of design techniques on a central and critical activity in designing Object- Oriented systems, behaviour allocation, implemented by assigning responsibilities to classes. Two alternative designing methods were used; Rational Unified Process (RUP) versus ICONIX method. Two groups of undergraduate students participated, each performing on one of the two designing methods. The subjects designed, using UML, a given use-case and a domain model, in order to assess the degree of their effectiveness in assigning methods in classes, examined by three quality factors: completeness, correctness and consistency. The results indicate that concerning effort, completeness, and consistency participants in RUP method performed more effectively than those performing in ICONIX method

Abstract: In spite of numerous traditional and agile software project management models proposed, process and project modeling still remains an open issue. This paper proposes a Bayesian network (BN) approach for modeling software project management antipatterns. This approach provides a framework for project managers, who would like to model the cause-effect relationships that underlie an antipattern, taking into account the inherent uncertainty of a software project. The approach is exemplified through a specific BN model of an antipattern. The antipattern is modeled using the empirical results of a controlled experiment on extreme programming (XP) that investigated the impact of developer personalities and temperaments on communication, collaboration-pair viability and effectiveness in pair programming. The resulting BN model provides the precise mathematical model of a project management antipattern and can be used to measure and handle uncertainty in mathematical terms.

Abstract: This paper presents two controlled experiments (a pilot and the main one) investigating the impact of developer personalities and temperaments on communication, collaboration-pair viability and ultimately effectiveness in pair programming. The objective of the experiments was to compare pairs of mixed/ heterogeneous developer personalities and temperaments with pairs of the same personalities and temperaments, in terms of pair effectiveness. Pair effectiveness is expressed in terms of pair performance, measured by communication, velocity, productivity and customer satisfaction, and pair collaboration-viability measured by developers� satisfaction, knowledge acquisition and participation (collaboration satisfaction ratio, nuisance ratio, voluntary or mandatory preference, and driver or navigator preference). The results have shown that there is significant difference between the two groups, indicating better communication and collaboration-viability for the pairs with mixed personalities/temperaments.

Abstract: This study concerns the formal evaluation of a resource-effective Distance Learning Environment (DLE) created to deliver a course on UML sequence diagrams to university-level students, divided into control and treatment groups. An ad-hoc resource-effective DLE was constructed to deliver instruction to the treatment group, while the control group was taught in a traditional face-to-face way. The main point of concern is whether a resource-effective DLE can be as effective for the treatment group, as the face-to-face lecture is for the control group, in terms of gaining mastery on the domain. The novelty of this approach is the �imitation� of a traditional lecture, which constitutes the resource-effective approach of a DLE. So, a controlled experiment was organized and executed, in order to measure the participants� performance in both groups. The results have shown no statistically significant difference for both groups of students. So, it can be argued that in the context of this experiment and by following a DLE-design close enough to the traditional face-to-face approach, one can obtain equally good results using distance learning as with the traditional system. However, a number of concerns remain and lot of future work is inevitable in order to generalize the results of this work on other domains as well and to clarify the proposed approach in detail.

Abstract: This paper presents a replication study of a controlled experiment, investigating the impact of many design characteristics on one of the most desirable quality factors, modifiability. Two alternative design structures were used; a responsibility-driven (RD) versus a control-oriented �mainframe� (MF) design. Two groups of undergraduate students participated, each performing on one of the two designs. The subjects designed, implemented in Java, and tested a set of three maintenance tasks in order to assess the degree of their understanding, effort, and performance. The results indicate that the RD version due to its delocalised structure, exhibited higher correctness, better extensibility, and design stability, than the MF version. In order to provide an objective assessment of the differences between the two versions, a considerable number of metrics were used on the delivered solutions, quantifying separately each produced design�s characteristics.

Abstract: Modern software companies are faced with the problem of training or updating their software engineers in UML topics. Because of limited time availability, often this becomes a difficult and expensive task. The study presented in this paper is a controlled experiment, concerning the ability to learn UML Sequence Diagrams, by means of two different approaches: The Traditional learning approach, learning in a classroom with the presence of a teacher and the Distance learning approach using web-based instructional material. The latter offers more flexibility to a software company, since the trainees need not interrupt their scheduled assignments. The core issue of investigation is whether Distance learning can be as effective as Traditional learning, when a software engineer must learn the UML language. A controlled experiment, comparing the two learning approaches, was performed with the participation of 49 students, separated into two groups. The results of the study show that there is no statistically significant difference between the two groups, indicating that Traditional place-based and Distance learning courses can both be effective methods for delivering course information. Therefore, the Distance learning approach seems to be appropriate for teaching UML.

Abstract: In this paper we discuss an empirical study about the success and difficulties 15 Greek software companies experienced applying Extreme Programming [1] as a holistic system in software development. Based on a generic XP system including feedback influences and using as a research tool a cause-effect model including social-technical affecting factors, the study statistically evaluates XP practices application by the software companies. Data were collected from 30 managers and developers, using the sample survey technique with questionnaires and interviews, in a time period of six months. Practices were analysed separately using Descriptive Statistics and as a whole by building up different models using stepwise Discriminant Analysis. The results have shown that companies, facing various problems with some practices, prefer to develop their own tailored XP method and way of working-practices to meet their requirements.

Abstract: The field of knowledge known as Empirical Software Engineering suggests the application of experimental methods in order to discover and de-scribe characteristics of the process and results derived from new methodologies, such as agile formal methods. In this paper we present the methodology needed for conducting formal experiments and we review related work done in the field of the agile formal methods. At the end of the paper, we report on our experimentation work up to now and our suggestions on future work in this important field of research.

Abstract: The application of experimental methods for empirical evaluation in object oriented technology and in agile methods constituted the main objective of this dissertation. In the context of object orientation the aim of this dissertation was to research the possibility of evaluation of the quality of alternative object oriented designs. Furthermore, another objective in the context of object orientation was to carry out research in the possibility of teaching UML through an Open and Distant Learning Environment. In order to achieve these objectives we organized and executed two controlled experiments. The first experiment addressed the issue of alternative design structures, a responsibility-driven (distributed) approach versus a mainframe or control-oriented approach. The results have indicated that the responsibility-driven design due to its delocalised structure, exhibited higher correctness, better extensibility, and design stability, than the mainframe design. The second experiment focused on the comparison of an ad-hoc resource-effective Open and Distant Learning Environment, which has been specifically created for teaching UML to students, with the traditional teaching environment. The results of the experiment have indicated that teaching UML through an Open and Distant Learning Environment can be equally productive as the tradi-tional teaching approach. In the context of agile methods and extreme programming we have emphasized our research interests in three different research areas, by applying two of the most important assessment and evaluation methods of the empirical software engineering. We first organized and carried out an extended field study in order to research the ex-tend and the means through which agile methods and extreme programming are applied in the Greek software industry. This is the first attempt to research this topic in this area and was carried out in fifteen software companies, during a time period of six months. The results have indicated that the success factors in their implementation were pair programming, test driven development, as well as the interactions and hidden dependencies between the practices. Furthermore, the results have showed that companies prefer to develop their own tailored XP method and way of working to meet their specific requirements due to problems with some of the practices. In addition, we carried out a survey study in an attempt to redefine the metrics and measurements that are used in agile methods and extreme programming. The results of this study have indicated that several new and many of the existing traditional software engineering metrics are used in agile methods. Many of the metrics proposed by us in this study have been used in our experiments. One of the most important findings of this research is the lack of measurements and metrics in the early stages of the development phase. Finally, we organized and executed a control experiment which aimed to evaluate a certain aspect of the implementation of the pair programming practice. The results of this experiment have showed that developer pairs with mixed personalities and temperaments are more effective than pairs with the same personality and temperament. From the conclusions of this dissertation it is clear that experimental techniques contribute effectively in the evaluation, assessment and improvement of important software engineering subjects. The main contribution of the dissertation is to present a methodological framework for the organization and implementation of the experimental evaluation, through different studies. The proposed future experimental research work is necessary for further evaluation and improvement of the two popular fields of software engineering, namely the object oriented technology and agile methods.