Exploring a Bayesian and linear approach to requirements traceability

Context

For large software projects it is important to have some traceability between artefacts from different phases (e.g.requirements, designs, code), and between artefacts and the involved developers. However, if the capturing of traceability information during the project is felt as laborious to developers, they will often be sloppy in registering the relevant traceability links so that the information is incomplete. This makes automated tool-based collection of traceability links a tempting alternative, but this has the opposite challenge of generating too many potential trace relationships, not all of which are equally relevant.

Objective

This paper evaluates how to rank such auto-generated trace relationships.

Method

We present two approaches for such a ranking: a Bayesian technique and a linear inference technique. Both techniques depend on the interaction event trails left behind by collaborating developers while working within a development tool.

Results

The outcome of a preliminary study suggest the advantage of the linear approach, we also explore the challenges and potentials of the two techniques.

Conclusion

The advantage of the two techniques is that they can be used to provide traceability insights that are contextual and would have been much more difficult to capture manually. We also present some key lessons learnt during this research.     

A test-driven approach to code search and its application to the reuse of auxiliary functionality

Context

Software developers spend considerable effort implementing auxiliary functionality used by the main features of a system (e.g., compressing/decompressing files, encryption/decription of data, scaling/rotating images). With the increasing amount of open source code available on the Internet, time and effort can be saved by reusing these utilities through informal practices of code search and reuse. However, when this type of reuse is performed in an ad hoc manner, it can be tedious and error-prone: code results have to be manually inspected and integrated into the workspace.

Objective

In this paper we introduce and evaluate the use of test cases as an interface for automating code search and reuse. We call our approach Test-Driven Code Search (TDCS). Test cases serve two purposes: (1) they define the behavior of the desired functionality to be searched; and (2) they test the matching results for suitability in the local context. We also describe CodeGenie, an Eclipse plugin we have developed that performs TDCS using a code search engine called Sourcerer.

Method

Our evaluation consists of two studies: an applicability study with 34 different features that were searched using CodeGenie; and a performance study comparing CodeGenie, Google Code Search, and a manual approach.

Results

Both studies present evidence of the applicability and good performance of TDCS in the reuse of auxiliary functionality.

Conclusion

This paper presents an approach to source code search and its application to the reuse of auxiliary functionality. Our exploratory evaluation shows promising results, which motivates the use and further investigation of TDCS.     

Conducting a Business Ethnography in Global Software Development projects of small German enterprises

Context

Studying work practices in the context of Global Software Development (GSD) projects entails multiple opportunities and challenges for the researchers. Understanding and tackling these challenges requires a careful and rigor application of research methods.

Objective

We want to contribute to the understanding of the challenges of studying GSD by reflecting on several obstacles we had to deal with when conducting ethnographically-informed research on offshoring in German small to medium-sized enterprises.

Method

The material for this paper is based on reflections and field notes from two research projects: an exploratory ethnographic field study, and a study that was framed as a Business Ethnography. For the analysis, we took a Grounded Theory-oriented coding and analysis approach in order to identify issues and challenges documented in our research notes.

Results

We introduce the concept of Business Ethnography and discuss our experiences of adapting and implementing this action research concept for our study. We identify and discuss three primary issues: understanding complex global work practices from a local perspective, adapting to changing interests of the participants, and dealing with micro-political frictions between the cooperating sites.

Conclusions

We identify common interests between the researchers and the companies as a challenge and chance for studies on offshoring. Building on our experiences from the field, we argue for an active conceptualization of struggles and conflicts in the field as well as for extending the role of the ethnographer to that of a learning mediator.     

A method for assessing confidence in requirements analysis

Context

During development managers, analysts and designers often need to know whether enough requirements analysis work has been done and whether or not it is safe to proceed to the design stage.

Objective

This paper describes a new, simple and practical method for assessing our confidence in a set of requirements.

Method

We identified four confidence factors and used a goal oriented framework with a simple ordinal scale to develop a method for assessing confidence. We illustrate the method and show how it has been applied to a real systems development project.

Results

We show how assessing confidence in the requirements could have revealed problems in this project earlier and so saved both time and money.

Conclusion

Our meta-level assessment of requirements provides a practical and pragmatic method that can prove useful to managers, analysts and designers who need to know when sufficient requirements analysis has been performed.     

The longitudinal, chronological case study research strategy: A definition, and an example from IBM Hursley Park

Context

There is surprisingly little empirical software engineering research (ESER) that has analysed and reported the rich, fine-grained behaviour of phenomena over time using qualitative and quantitative data. The ESER community also increasingly recognises the need to develop theories of software engineering phenomena e.g. theories of the actual behaviour of software projects at the level of the project and over time.

Objective

To examine the use of the longitudinal, chronological case study (LCCS) as a research strategy for investigating the rich, fine-grained behaviour of phenomena over time using qualitative and quantitative data.

Method

Review the methodological literature on longitudinal case study. Define the LCCS and demonstrate the development and application of the LCCS research strategy to the investigation of Project C, a software development project at IBM Hursley Park. Use the study to consider prospects for LCCSs, and to make progress on a theory of software project behaviour.

Results

LCCSs appear to provide insights that are hard to achieve using existing research strategies, such as the survey study. The LCCS strategy has basic requirements that data is time-indexed, relatively fine-grained and collected contemporaneous to the events to which the data refer. Preliminary progress is made on a theory of software project behaviour.

Conclusion

LCCS appears well suited to analysing and reporting rich, fine-grained behaviour of phenomena over time.     

Towards an ontology-based retrieval of UML Class Diagrams

Context

Software Reuse has always been an important area amongst software companies in order to increase their productivity and the quality of their products, but code reuse is not the only answer for this. Nowadays, reuse techniques proposals include software designs or even software specifications. Therefore, this research focuses on software design, specifically on UML Class Diagrams. A semantic technology has been applied to facilitate the retrieval process for an effective reuse.

Objective

This research proposes an ontology-based retrieval technique by semantic similarity in order to support effective retrieval process for UML Class Diagrams. Since UML Class Diagrams are a de facto standard in the design stages of a Software Development Process, a good technique is needed to reuse them, i.e. reusing during the design stage instead of just the coding stages.

Method

An application ontology modeled using UML specifications was designed to compare UML Class Diagram element types. To measure their similarity, a survey was conducted amongst UML experts. Query expansion was improved by a domain ontology supporting the retrieval phase. The calculus of minimal distances in ontologies was solved using a shortest path algorithm.

Results

The case study shows the domain ontology importance in the UML Class Diagram retrieval process as well as the importance of an element type expansion method, such as an application ontology. A correlation between the query complexity and retrieved elements has been identified, by analyzing results. Finally, a positive Return of Investment (ROI) was estimated using Poulin’s Model.

Conclusion

Because Software Reuse has not to be limited to the coding stage, approaches to reuse design stage must be developed, i.e. UML Class Diagrams reuse. This approach proposes a technique for UML Class Diagrams retrieval, which is one important step towards reuse. Semantic technology combined with information retrieval improves the retrieval results.     

Software process improvement success factors for small and medium Web companies: A qualitative study

Context

The context of this research is software process improvement (SPI) in small and medium Web companies.

Objective

The primary objective of this paper is to identify software process improvement (SPI) success factors for small and medium Web companies.

Method

To achieve this goal, we conducted semi-structured, open-ended interviews with 21 participants representing 11 different companies in Pakistan, and analyzed the data qualitatively using the Glaserian strand of grounded theory research procedures. The key steps of these procedures that were employed in this research included open coding, focused coding, theoretical coding, theoretical sampling, constant comparison, and scaling up.

Results

An initial framework of key SPI success factors for small and medium Web companies was proposed, which can be of use for small and medium Web companies engaged in SPI. The paper also differentiates between small and medium Web companies and analyzes crucial SPI requirements for companies operating in the Web development domain.

Conclusion

The results of this work, in particular the use of qualitative techniques - allowed us to obtain rich insight into SPI success factors for small and medium Web companies. Future work comprises the validation of the SPI success factors with small and medium Web companies.     

A pilot study to compare programming effort for two parallel programming models

Context

Writing software for the current generation of parallel systems requires significant programmer effort, and the community is seeking alternatives that reduce effort while still achieving good performance.

Objective

Measure the effect of parallel programming models (message-passing vs. PRAM-like) on programmer effort.

Design, setting, and subjects

One group of subjects implemented sparse-matrix dense-vector multiplication using message-passing (MPI), and a second group solved the same problem using a PRAM-like model (XMTC). The subjects were students in two graduate-level classes: one class was taught MPI and the other was taught XMTC.

Main outcome measures

Development time, program correctness.

Results

Mean XMTC development time was 4.8 h less than mean MPI development time (95% confidence interval, 2.0-7.7), a 46% reduction. XMTC programs were more likely to be correct, but the difference in correctness rates was not statistically significant (p = .16).

Conclusions

XMTC solutions for this particular problem required less effort than MPI equivalents, but further studies are necessary which examine different types of problems and different levels of programmer experience.     

Systematic literature review of machine learning based software development effort estimation models

Context

Software development effort estimation (SDEE) is the process of predicting the effort required to develop a software system. In order to improve estimation accuracy, many researchers have proposed machine learning (ML) based SDEE models (ML models) since 1990s. However, there has been no attempt to analyze the empirical evidence on ML models in a systematic way.

Objective

This research aims to systematically analyze ML models from four aspects: type of ML technique, estimation accuracy, model comparison, and estimation context.

Method

We performed a systematic literature review of empirical studies on ML model published in the last two decades (1991-2010).

Results

We have identified 84 primary studies relevant to the objective of this research. After investigating these studies, we found that eight types of ML techniques have been employed in SDEE models. Overall speaking, the estimation accuracy of these ML models is close to the acceptable level and is better than that of non-ML models. Furthermore, different ML models have different strengths and weaknesses and thus favor different estimation contexts.

Conclusion

ML models are promising in the field of SDEE. However, the application of ML models in industry is still limited, so that more effort and incentives are needed to facilitate the application of ML models. To this end, based on the findings of this review, we provide recommendations for researchers as well as guidelines for practitioners.     

Beyond the customer: Opening the agile systems development process

Context

A particular strength of agile systems development approaches is that they encourage a move away from ‘introverted’ development, involving the customer in all areas of development, leading to more innovative and hence more valuable information system. However, a move toward open innovation requires a focus that goes beyond a single customer representative, involving a broader range of stakeholders, both inside and outside the organisation in a continuous, systematic way.

Objective

This paper provides an in-depth discussion of the applicability and implications of open innovation in an agile environment.

Method

We draw on two illustrative cases from industry.

Results

We highlight some distinct problems that arose when two project teams tried to combine agile and open innovation principles. For example, openness is often compromised by a perceived competitive element and lack of transparency between business units. In addition, minimal documentation often reduce effective knowledge transfer while the use of short iterations, stand-up meetings and presence of on-site customer reduce the amount of time for sharing ideas outside the team.

Conclusion

A clear understanding of the inter- and intra-organisational applicability and implications of open innovation in agile systems development is required to address key challenges for research and practice.