The agile requirements refinery: Applying SCRUM principles to software product management

Context

Although agile software development methods such as SCRUM and DSDM are gaining popularity, the consequences of applying agile principles to software product management have received little attention until now.

Objective

In this paper, this gap is filled by the introduction of a method for the application of SCRUM principles to software product management.

Method

A case study research approach is employed to describe and evaluate this method.

Results

This has resulted in the ‘agile requirements refinery’, an extension to the SCRUM process that enables product managers to cope with complex requirements in an agile development environment. A case study is presented to illustrate how agile methods can be applied to software product management.

Conclusions

The experiences of the case study company are provided as a set of lessons learned that will help others to apply agile principles to their software product management process.     

Conceptual scheduling model and optimized release scheduling for agile environments

Context

Release scheduling deals with the selection and assignment of deliverable features to a sequence of consecutive product deliveries while several constraints are fulfilled. Although agile software development represents a major approach to software engineering, there is no well-established conceptual definition and sound methodological support of agile release scheduling.

Objective

To propose a solution, we present, (1) a conceptual model for agile scheduling, and (2) a novel multiple knapsack-based optimization model with (3) a branch-and-bound optimization algorithm for agile release scheduling.

Method

To evaluate our model simulations were carried out seven real life and several generated data sets.

Results

The developed algorithm strives to prevent resource overload and resource underload, and mitigates risks of delivery slippage.

Conclusion

The results of the experiment suggest that this approach can provide optimized semi-automatic release schedule generations and more informed and established decisions utilizing what-if-analysis on the fly to tailor the best schedule for the specific project context.     

The impact of inadequate customer collaboration on self-organizing Agile teams

Context

Customer collaboration is a vital feature of Agile software development.

Objective

This article addresses the importance of adequate customer involvement on Agile projects, and the impact of different levels of customer involvement on real-life Agile projects.

Method

We conducted a Grounded Theory study involving 30 Agile practitioners from 16 software development organizations in New Zealand and India, over a period of 3 years.

Results

We discovered that Lack of Customer Involvement was one of the biggest challenges faced by Agile teams. Customers were not as involved on these Agile projects as Agile methods demand. We describe the causes of inadequate customer collaboration, its adverse consequences on self-organizing Agile teams, and Agile Undercover — a set of strategies used by the teams to practice Agile despite insufficient or ineffective customer involvement.

Conclusion

Customer involvement is important on Agile projects. Inadequate customer involvement causes adverse problems for Agile teams. The Agile Undercover strategies we’ve identified can assist Agile teams facing similar lack of customer involvement.     

Drivers of agile software development use: Dialectic interplay between benefits and hindrances

Context

Agile software development with its emphasis on producing working code through frequent releases, extensive client interactions and iterative development has emerged as an alternative to traditional plan-based software development methods. While a number of case studies have provided insights into the use and consequences of agile, few empirical studies have examined the factors that drive the adoption and use of agile.

Objective

We draw on intention-based theories and a dialectic perspective to identify factors driving the use of agile practices among adopters of this software development methodology.

Method

Data for the study was gathered through an anonymous online survey of software development professionals. We requested participation from members of a selected list of online discussion groups, and received 98 responses.

Results

Our analyses reveal that subjective norm and training play a significant role in influencing software developers’ use of agile processes and methods, while perceived benefits and perceived limitations are not primary drivers of agile use among adopters. Interestingly, perceived benefit emerges as a significant predictor of agile use only if adopters face hindrances to their agile practices.

Conclusion

We conclude that research in the adoption of software development innovations should examine the effects of both enabling and detracting factors and the interactions between them. Since training, subjective norm, and the interplay between perceived benefits and perceived hindrances appear to be key factors influencing the adoption of agile methods, researchers can focus on how to (a) perform training on agile methods more effectively, (b) facilitate the dialog between developers and managers about perceived benefits and hindrances, and (c) capitalize on subjective norm to publicize the benefits of agile methods within an organization. Further, when managing the transition to new software development methods, we recommend that practitioners adapt their strategies and tactics contingent on the extent of perceived hindrances to the change.     

The relationship between organizational culture and the deployment of agile methods

Context

Systems development normally takes place in a specific organizational context, including organizational culture. Previous research has identified organizational culture as a factor that potentially affects the deployment systems development methods.

Objective

The purpose is to analyze the relationship between organizational culture and the post-adoption deployment of agile methods.

Method

This study is a theory development exercise. Based on the Competing Values Model of organizational culture, the paper proposes a number of hypotheses about the relationship between organizational culture and the deployment of agile methods.

Results

Inspired by the agile methods thirteen new hypotheses are introduced and discussed. They have interesting implications, when contrasted with ad hoc development and with traditional systems development methods.

Conclusion

Because of the conceptual richness of organizational culture and the ambiguity of the concept of agility the relationship between organizational culture and the deployment of agile systems development forms a rich and interesting research topic. Recognizing that the Competing Values Model represents just one view of organizational culture, the paper introduces a number of alternative conceptions and identifies several interesting paths for future research into the relationship between organizational culture and agile methods deployment.     

Post-agility: What follows a decade of agility?

Context

Agile information systems development (ISD) has received much attention from both the practitioner and researcher community over the last 10-15 years. However, it is still unclear what precisely constitutes agile ISD.

Objective

Based on four empirical studies conducted over a 10-year time period from 1999 to 2008 the objective of this paper is to show how the meaning and practice of agile ISD has evolved over time and on this basis to speculate about what comes next.

Method

Four phases of research has been conducted, using a grounded theory approach. For each research phase qualitative interviews were held in American and/or Danish companies and a grounded theory was inductively discovered by careful data analysis. Subsequently, the four unique theories have been analyzed for common themes, and a global theory was identified across the empirical data.

Results

In 1999 companies were developing software at high-speed in a desperate rush to be first-to-market. In 2001 a new high-speed/quick results development process had become established practice. In 2003 changes in the market created the need for a more balanced view on speed and quality, and in 2008 companies were successfully combining agile and plan-driven approaches to achieve the benefits of both. The studies reveal a two-stage pattern in which dramatic changes in the market causes disruption of established practices and process adaptations followed by consolidation of lessons learnt into a once again stable software development process.

Conclusion

The cyclical history of punctuated process evolution makes it possible to distinguish pre-agility from current practices (agility), and on this basis, to speculate about post-agility: a possible next cycle of software process evolution concerned with proactively pursuing the dual goal of agility and alignment through a diversity of means.     

Hybrid methodology for data warehouse conceptual design by UML schemas

Context

Data warehouse conceptual design is based on the metaphor of the cube, which can be derived from either requirement-driven or data-driven methodologies. Each methodology has its own advantages. The first allows designers to obtain a conceptual schema very close to the user needs but it may be not supported by the effective data availability. On the contrary, the second ensures a perfect traceability and consistence with the data sources—in fact, it guarantees the presence of data to be used in analytical processing—but does not preserve from missing business user needs. To face this issue, the necessity emerged in the last years to define hybrid methodologies for conceptual design.

Objective

The objective of the paper is to use a hybrid methodology based on different multidimensional models in order to gather all advantages of each of them.

Method

The proposed methodology integrates the requirement-driven strategy with the data-driven one, in that order, possibly performing alterations of functional dependencies on UML multidimensional schemas reconciled with data sources.

Results

As case study, we illustrate how our methodology can be applied to the university environment. Furthermore, we evaluate quantitatively the benefits of this methodology by comparing it with some popular and conventional methodologies.

Conclusion

In conclusion, we highlight how the hybrid methodology improves the conceptual schema quality. Finally, we outline our present work devoted to introduce automatic design techniques in the methodology on the basis of the logical programming.     

Quantitative release planning in extreme programming

Context

Extreme Programming (XP) is one of the most popular agile software development methodologies. XP is defined as a consistent set of values and practices designed to work well together, but lacks practices for project management and especially for supporting the customer role. The customer representative is constantly under pressure and may experience difficulties in foreseeing the adequacy of a release plan.

Objective

To assist release planning in XP by structuring the planning problem and providing an optimization model that suggests a suitable release plan.

Method

We develop an optimization model that generates a release plan taking into account story size, business value, possible precedence relations, themes, and uncertainty in velocity prediction. The running-time feasibility is established through computational tests. In addition, we provide a practical heuristic approach to velocity estimation.

Results

Computational tests show that problems with up to six themes and 50 stories can be solved exactly. An example provides insight into uncertainties affecting velocity, and indicates that the model can be applied in practice.

Conclusion

An optimization model can be used in practice to enable the customer representative to take more informed decisions faster. This can help adopting XP in projects where plan-driven approaches have traditionally been used.     

Software engineering projects may fail before they are started: Post-mortem analysis of five cancelled projects

Context

Software project cancellations are often caused by mistakes made during the project, and such cancellations make a strong economic impact. We analyzed five cancelled software engineering projects. One case was an internal product development project of a company that sells products to its customers. The other four cases were different software engineering projects, and outcomes of these projects were planned to be delivered to external customers.

Objective

This study reports a post-mortem analysis of five software engineering projects with the aim of providing more knowledge about the reasons for cancellation decisions and the causes behind those reasons.

Methods

The research method is case study. A method for a document-based post-mortem analysis was developed and post-mortem analysis was performed. All project documentation was available for analysis.

Results

The reasons for the cancellation decisions were well-known ones. In four cases of five, the outcome of the project was to be delivered to an external customer, but in these cases the causes of the cancellation reasons were not found from the normal project documentation. In these cases the cause of the cancellation originated in a phase before the start of the project and therefore the project was doomed before it was started.

Conclusion

It is reasonable to suggest that a remarkable portion of project cancellations are due to mistakes made before the project is started in the case of contract-based software engineering projects.     

Design guidelines for software processes knowledge repository development

Context

Staff turnover in organizations is an important issue that should be taken into account mainly for two reasons:

1.

Employees carry an organization’s knowledge in their heads and take it with them wherever they go

2.

Knowledge accessibility is limited to the amount of knowledge employees want to share

Objective

The aim of this work is to provide a set of guidelines to develop knowledge-based Process Asset Libraries (PAL) to store software engineering best practices, implemented as a wiki.

Method

Fieldwork was carried out in a 2-year training course in agile development. This was validated in two phases (with and without PAL), which were subdivided into two stages: Training and Project.

Results

The study demonstrates that, on the one hand, the learning process can be facilitated using PAL to transfer software process knowledge, and on the other hand, products were developed by junior software engineers with a greater degree of independence.

Conclusion

PAL, as a knowledge repository, helps software engineers to learn about development processes and improves the use of agile processes.     

Agile methods rapidly replacing traditional methods at Nokia: A survey of opinions on agile transformation

Context

Many organizations have started to deploy agile methods, but so far there exist only a few studies on organization-wide transformations. Are agile methods here to stay? Some claim that agile software development methods are in the mainstream adoption phase in the software industry, while others hope that those are a passing fad. The assumption here is that if agile would not provide real improvement, adopters would be eager at first but turn pessimistic after putting it into practice.

Objective

Despite the growing amount of anecdotal evidence on the success of agile methods across a wide range of different real-life development settings, scientific studies remain scarce. Even less is known about the perception of the impacts of agile transformation when it is deployed in a very large software development environment, and whether agile methods are here to stay. This study aims to fill that gap by providing evidence from a large-scale agile transformation within Nokia. While we have yet to confirm these findings with solid quantitative data, we believe that the perception of the impacts already pinpoints the direction of the impacts of large-scale agile transformation.

Method

The data were collected using a questionnaire. The population of the study contains more than 1000 respondents in seven different countries in Europe, North America, and Asia.

Results

The results reveal that most respondents agree on all accounts with the generally claimed benefits of agile methods. These benefits include higher satisfaction, a feeling of effectiveness, increased quality and transparency, increased autonomy and happiness, and earlier detection of defects. Finally, 60% of respondents would not like to return to the old way of working.

Conclusion

While the perception of the impact of agile methods is predominantly positive, several challenge areas were discovered. However, based on this study, agile methods are here to stay.     

A unit test approach for database schema evolution

Context

The constant changes in today’s business requirements demand continuous database revisions. Hence, database structures, not unlike software applications, deteriorate during their lifespan and thus require refactoring in order to achieve a longer life span. Although unit tests support changes to application programs and refactoring, there is currently a lack of testing strategies for database schema evolution.

Objective

This work examines the challenges for database schema evolution and explores the possibility of using various testing strategies to assist with schema evolution. Specifically, the work proposes a novel unit test approach for the application code that accesses databases with the objective of proactively evaluating the code against the altered database.

Method

The approach was validated through the implementation of a testing framework in conjunction with a sample application and a relatively simple database schema. Although the database schema in this study was simple, it was nevertheless able to demonstrate the advantages of the proposed approach.

Results

After changes in the database schema, the proposed approach found all SELECT statements as well as the majority of other statements requiring modifications in the application code. Due to its efficiency with SELECT statements, the proposed approach is expected to be more successful with database warehouse applications where SELECT statements are dominant.

Conclusion

The unit test approach that accesses databases has proven to be successful in evaluating the application code against the evolved database. In particular, the approach is simple and straightforward to implement, which makes it easily adoptable in practice.     

Reconciling software development models: A quasi-systematic review

Purpose

The purpose of this paper is to characterize reconciliation among the plan-driven, agile, and free/open source software models of software development.

Design/methodology/approach

An automated quasi-systematic review identified 42 papers, which were then analyzed.

Findings

The main findings are: there exist distinct - organization, group and process - levels of reconciliation; few studies deal with reconciliation among the three models of development; a significant amount of work addresses reconciliation between plan-driven and agile development; several large organizations (such as Microsoft, Motorola, and Philips) are interested in trying to combine these models; and reconciliation among software development models is still an open issue, since it is an emerging area and research on most proposals is at an early stage.

Research limitations

Automated searches may not capture relevant papers in publications that are not indexed. Other data sources not amenable to execution of the protocol were not used. Data extraction was performed by only one researcher, which may increase the risk of threats to internal validity.

Implications

This characterization is important for practitioners wanting to be current with the state of research. This review will also assist the scientific community working with software development processes to build a common understanding of the challenges that must be faced, and to identify areas where research is lacking. Finally, the results will be useful to software industry that is calling for solutions in this area.

Originality/value

There is no other systematic review on this subject, and reconciliation among software development models is an emerging area. This study helps to identify and consolidate the work done so far and to guide future research. The conclusions are an important step towards expanding the body of knowledge in the field.     

Reliability analysis and optimal version-updating for open source software

Context

Although reliability is a major concern of most open source projects, research on this problem has attracted attention only recently. In addition, the optimal version-dating for open source software considering its special properties is not yet discussed.

Objective

In this paper, the reliability analysis and optimal version-updating for open source software are studied.

Method

A modified non-homogeneous Poisson process model is developed for open source software reliability modeling and analysis. Based on this model, optimal version-updating for open source software is investigated as well. In the decision process, the rapid release strategy and the level of reliability are the two most important factors. However, they are essentially contradicting with each other. In order to consider these two conflicting factors simultaneously, a new decision model based on multi-attribute utility theory is proposed.

Results

Our models are tested on the real world data sets from two famous open source projects: Apache and GNOME. It is found that traditional software reliability models provide overestimations of the reliability of open source software. In addition, the proposed decision model can help management to make a rational decision on the optimal version-updating for open source software.

Conclusion

Empirical results reveal that the proposed model for open source software reliability can describe the failure process more accurately. Furthermore, it can be seen that the proposed decision model can assist management to appropriately determine the optimal version-update time for open source software.     

Partnering effects on user-developer conflict and role ambiguity in information system projects

Context

Information system development (ISD) has been plagued with high failure rates. This is partially due to the activities being a combination of both a technical and social processes involving stakeholders with conflicting interests.

Objective

Existing software risk management theories and frameworks offer limited suggestions for actions that can be taken to reduce the chance of failure of ISD projects. Our objective is to examine the connections among some of the more important user related risks in order to shed light on how specific strategies enhance the chance of project success.

Method

We conducted a sample of information systems project managers to test a multivariate model to explain the impact of pursuing a partnership with users on the conflicts that arise between users and developers, role ambiguity, and subsequent impact on project performance.

Results

The proposed model was supported, suggesting that user-developer conflict and role ambiguity have a negative impact on performance estimation difficulty, which negatively affects project performance.

Conclusion

Pursuit of project partnering yields a number of significant relationships in the model indicating an organization can implement practices that reduce risks associated with role ambiguity and conflict in system development projects.     

A systematic mapping study of software product lines testing

Context

In software development, Testing is an important mechanism both to identify defects and assure that completed products work as specified. This is a common practice in single-system development, and continues to hold in Software Product Lines (SPL). Even though extensive research has been done in the SPL Testing field, it is necessary to assess the current state of research and practice, in order to provide practitioners with evidence that enable fostering its further development.

Objective

This paper focuses on Testing in SPL and has the following goals: investigate state-of-the-art testing practices, synthesize available evidence, and identify gaps between required techniques and existing approaches, available in the literature.

Method

A systematic mapping study was conducted with a set of nine research questions, in which 120 studies, dated from 1993 to 2009, were evaluated.

Results

Although several aspects regarding testing have been covered by single-system development approaches, many cannot be directly applied in the SPL context due to specific issues. In addition, particular aspects regarding SPL are not covered by the existing SPL approaches, and when the aspects are covered, the literature just gives brief overviews. This scenario indicates that additional investigation, empirical and practical, should be performed.

Conclusion

The results can help to understand the needs in SPL Testing, by identifying points that still require additional investigation, since important aspects regarding particular points of software product lines have not been addressed yet.     

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.     

Assessing PSP effect in training disciplined software development: A Plan-Track-Review model

Context

In training disciplined software development, the PSP is said to result in such effect as increased estimation accuracy, better software quality, earlier defect detection, and improved productivity. But a systematic mechanism that can be easily adopted to assess and interpret PSP effect is scarce within the existing literature.

Objective

The purpose of this study is to explore the possibility of devising a feasible assessment model that ties up critical software engineering values with the pertinent PSP metrics.

Method

A systematic review of the literature was conducted to establish such an assessment model (we called a Plan-Track-Review model). Both mean and median approaches along with a set of simplified procedures were used to assess the commonly accepted PSP training effects. A set of statistical analyses further followed to increase understanding of the relationships among the PSP metrics and to help interpret the application results.

Results

Based on the results of this study, PSP training effect on the controllability, manageability, and reliability of a software engineer is quite positive and largely consistent with the literature. However, its effect on one’s predictability on project in general (and on project size in particular) is not implied as said in the literature. As for one’s overall project efficiency, our results show a moderate improvement. Our initial finding also suggests that a prior stage PSP effect could have an impact on later stage training outcomes.

Conclusion

It is concluded that this Plan-Track-Review model with the associated framework can be used to assess PSP effect regarding a disciplined software development. The generated summary report serves to provide useful feedback for both PSP instructors and students based on internal as well as external standards.     

API2MoL: Automating the building of bridges between APIs and Model-Driven Engineering

Context

A software artefact typically makes its functionality available through a specialized Application Programming Interface (API) describing the set of services offered to client applications. In fact, building any software system usually involves managing a plethora of APIs, which complicates the development process. In Model-Driven Engineering (MDE), where models are the key elements of any software engineering activity, this API management should take place at the model level. Therefore, tools that facilitate the integration of APIs and MDE are clearly needed.

Objective

Our goal is to automate the implementation of API-MDE bridges for supporting both the creation of models from API objects and the generation of such API objects from models. In this sense, this paper presents the API2MoL approach, which provides a declarative rule-based language to easily write mapping definitions to link API specifications and the metamodel that represents them. These definitions are then executed to convert API objects into model elements or vice versa. The approach also allows both the metamodel and the mapping to be automatically obtained from the API specification (bootstrap process).

Method

After implementing the API2MoL engine, its correctness was validated using several APIs. Since APIs are normally large, we then developed a tool to implement the bootstrap process, which was also validated.

Results

We provide a toolkit (language and bootstrap tool) for the creation of bridges between APIs and MDE. The current implementation focuses on Java APIs, although its adaptation to other statically typed object-oriented languages is straightforward. The correctness, expressiveness and completeness of the approach have been validated with the Swing, SWT and JTwitter APIs.

Conclusion

API2MoL frees developers from having to manually implement the tasks of obtaining models from API objects and generating such objects from models. This helps to manage API models in MDE-based solutions.