Diana Kirk

Software Systems as Complex Networks

As software systems become larger and more complex, in order to understand, manage and evolve these systems, we need better ways of characterizing and controlling their macroscopic properties. We suggest complex network theory may be useful for these purposes. In recent years, researchers have shown that many complex systems from different disciplines can be investigated as complex networks and most of them comply with a scale-free network model. We explore the view that a software system can be studied as a network with a number of components (classes) connected by dependency (integration) relationships; we call this network the component dependency network (CDN). The CDNs of several Java libraries and applications have been examined and all of them exhibit some scale-free characteristics. This result has some practical value including that it allows us to identify important components (classes) and thereby assists software maintenance and reengineering. We have built a tool to study software systems as complex networks. In the paper we also suggest ways of controlling and changing how systems evolve in order to improve their understandability and maintainability.

A flexible software process model

The development of software products is a complex activity with a large number of factors involved in defining success. As real-world experimentation is difficult and costly, researchers have used various techniques in an attempt to model the development process. This field of software process simulation has received substantial attention over the last twenty years. The aims have been to better understand the software development process and to mitigate the problems that continue to occur in the industry by providing support for management decision making.

On the differences between correct student solutions

We know that students solve problems in different ways, but we know little about the kinds of variation, or the degree of variation between these student generated solutions. In this paper, we propose a taxonomy that classifies the variation between correct student solutions in objective terms, and we show how the application of the taxonomy provides instructors with additional insight about the differences between student solutions. This taxonomy may be used to inform instructors in selecting examples of code for teaching purposes, and provides the possibility of automatically applying the taxonomy to existing solution sets.

Software Development Practices in New Zealand

Different kinds of process model are prescribed for software organizations, and each offers successful project outcomes if followed. There is little evidence that organizations strictly adhere to specific models. We surveyed 195 participants from 51 New Zealand (NZ) software organizations with a view to increasing our understanding of practice implementation in NZ. We found that practices are implemented inconsistently. The implication is that organizations do not follow any one process, either prescribed or adapted, but rather select practices on a project basis and according to some unknown guidelines. Our conclusion is that, rather than attempting to impose or adapt processes at an organizational level, we should instead aim to understand the rationale behind practice selection and how practices combine to make a coherent set. We also found a collaborative, informal, iterative approach to product development with issues around clarity and availability of requirements.

Raising healthy software systems

We elaborate on the analogy between humans and bespoke software systems and we use this analogy to inform an alternative perspective on the development and management of such systems.

Identifying risks in XP projects through process modelling

XP is a software development methodology that aims to address software project risks. However, risks for any project are dependent upon many factors and need to be assessed on a project-by-project basis. Indeed, under some circumstances, the practices that make up the XP discipline actually introduce risk into the process. Such risks must be understood in order that appropriate mitigation strategies and contingency plans might be put in place. In this paper, we introduce a process modelling framework, KiTe, and show how to use the framework as the basis for a systematic approach to identifying risk conditions inherent in XP projects.

An Ontological Analysis of a Proposed Theory for Software Development

There is growing acknowledgement within the software engineering community that a theory of software development is needed to integrate the myriad methodologies that are currently popular, some of which are based on opposing perspectives. We have been developing such a theory for a number of years. In this paper, we overview our theory and report on a recent ontological analysis of the theory constructs. We suggest that, once fully developed, this theory, or one similar to it, may be applied to support situated software development, by providing an overarching model within which software initiatives might be categorised and understood. Such understanding would inevitably lead to greater predictability with respect to outcomes.

Progress report on a proposed theory for software development

There is growing acknowledgement within the software engineering community that a theory of software development is needed to integrate the myriad methodologies that are currently popular, some of which are based on opposing perspectives. We have been developing such a theory for a number of years. In this position paper, we overview our theory along with progress made thus far. We suggest that, once fully developed, this theory, or one similar to it, may be applied to support situated software development, by providing an overarching model within which software initiatives might be categorised and understood. Such understanding would inevitably lead to greater predictability with respect to outcomes.