A case study validation of a knowledge-based approach for the selection of requirements engineering techniques

Requirements engineering (RE) is a critical phase in the software engineering process and plays a vital role in ensuring the overall quality of a software product. Recent research has shown that industry increasingly recognizes the importance of good RE practices and the use of appropriate RE techniques. However, due to the large number of RE techniques, requirements engineers find it challenging to select suitable techniques for a particular project. Unfortunately, technique selection based on personal experience has limitations with regards to the scope, effectiveness and suitability of the RE techniques for the project at hand. In this paper, a Knowledge-based Approach for the Selection of Requirements Engineering Techniques (KASRET) is proposed that helps during RE techniques selection. This approach has three major features. First, a library of requirements techniques was developed which includes detailed knowledge about RE techniques. Second, KASRET integrates advantages of different knowledge representation schemata and reasoning mechanisms. Thus, KASRET provides mechanisms for the management of knowledge about requirements techniques and support for RE process development. Third, as a major decision support mechanism, an objective function evaluates the overall ability and cost of RE techniques, which is helpful for the selection of RE techniques. This paper makes not only a contribution to RE but also to research and application of knowledge management and decision support in process development. A case study using an industrial project shows the support of KASRET for RE techniques selection.

A methodology for the classification of quality of requirements using machine learning techniques

ContextOne of the most important factors in the development of a software project is the quality of their requirements. Erroneous requirements, if not detected early, may cause many serious problems, such as substantial additional costs, failure to meet the expected objectives and delays in delivery dates. For these reasons, great effort must be devoted in requirements engineering to ensure that the project’s requirements results are of high quality. One of the aims of this discipline is the automatic processing of requirements for assessing their quality; this aim, however, results in a complex task because the quality of requirements depends mostly on the interpretation of experts and the necessities and demands of the project at hand.ObjectiveThe objective of this paper is to assess the quality of requirements automatically, emulating the assessment that a quality expert of a project would assess.MethodThe proposed methodology is based on the idea of learning based on standard metrics that represent the characteristics that an expert takes into consideration when deciding on the good or bad quality of requirements. Using machine learning techniques, a classifier is trained with requirements earlier classified by the expert, which then is used for classifying newly provided requirements.ResultsWe present two approaches to represent the methodology with two situations of the problem in function of the requirement corpus learning balancing, obtaining different results in the accuracy and the efficiency in order to evaluate both representations. The paper demonstrates the reliability of the methodology by presenting a case study with requirements provided by the Requirements Working Group of the INCOSE organization.ConclusionsA methodology that evaluates the quality of requirements written in natural language is presented in order to emulate the quality that the expert would provide for new requirements, with 86.1 of average in the accuracy.     

Portraying the practice of decision-making in requirements engineering: a case of large scale bespoke development

Complex decision-making is a prominent aspect of requirements engineering (RE) and the need for improved decision support for RE decision-makers has been identified by a number of authors in the research literature. A first step toward better decision support in requirements engineering is to understand multifaceted decision situations of decision-makers. In this paper, the focus is on RE decision-making in large scale bespoke development. The decision situation of RE decision-makers on a subsystem level has been studied at a systems engineering company and is depicted in this paper. These situations are described in terms of, e.g., RE decision matters, RE decision-making activities, and RE decision processes. Factors that affect RE decision-makers are also identified.     

需求工程的探讨

软件工程被分为需求、设计、实现、测试等几个阶段,其中需求阶段是一个项目的开端,也是项目成功的基石。在软件工程中,需求分析指的是在建立一个新的或改变一个现存的电脑系统时描写新系统的目的、范围、定义和功能时所要做的所有的工作。需求分析是软件工程中的一个关键过程。在这个过程中,系统分析员和软件工程师确定顾客的需要。只有在确定了这些需要后他们才能够分析和寻求新系统的解决方法。在软件工程的历史中,很长时间里人们一直认为需求分析是整个软件工程中最简单的一个步骤,但在过去十年中越来越多的人认识到它是整个过程中最关键的一个过程。假如在需求分析时分析者们未能正确地认识到顾客的需要的话,那么最后的软件实际上不可能达到顾客的需要,或者软件无法在规定的时间里完工。     

A requirements engineering process for control engineering software

This paper presents a novel approach for the specification of control engineering software. The proposal is based on software engineering techniques which have improved the performance and quality of software processes. Some of the best practices for the building of software products are included. An example of the proposal is given for the requirements specification of the 1992 ACC robust control benchmark.     

Using classification techniques for informal requirements in the requirements analysis-supporting system

In order to efficiently develop large-scale and complicated software, it is important for system engineers to correctly understand users’ requirements. Most requirements in large-scale projects are collected from various stakeholders located in various regions, and they are generally written in natural language. Therefore, the initial collected requirements must be classified into various topics prior to analysis phases in order to be usable as input in several requirements analysis methods. If this classification process is manually done by analysts, it becomes a time-consuming task. To solve this problem, we propose a new bootstrapping method which can automatically classify requirements sentences into each topic category using only topic words as the representative of the analysts’ views. The proposed method is verified through experiments using two requirements data sets: one written in English and the other in Korean. The significant performances were achieved in the experiments: the 84.28 and 87.91 F1 scores for the English and Korean data sets, respectively. As a result, the proposed method can provide an effective function for an Internet-based requirements analysis-supporting system so as to efficiently gather and analyze requirements from various and distributed stakeholders by using the Internet.     

Pair-wise comparisons versus planning game partitioning—experiments on requirements prioritisation techniques

The process of selecting the right set of requirements for a product release is dependent on how well the organisation succeeds in prioritising the requirements candidates. This paper describes two consecutive controlled experiments comparing different requirements prioritisation techniques with the objective of understanding differences in time-consumption, ease of use and accuracy. The first experiment evaluates Pair-wise comparisons and a variation of the Planning game. As the Planning game turned out as superior, the second experiment was designed to compare the Planning game to Tool-supported pair-wise comparisons. The results indicate that the manual pair-wise comparisons is the most time-consuming of the techniques, and also the least easy to use. Tool-supported pair-wise comparisons is the fastest technique and it is as easy to use as the Planning game. The techniques do not differ significantly regarding accuracy. Editor: Daniel Berry     

A measurement framework for assessing the maturity of requirements engineering process

Because requirements engineering (RE) problems are widely acknowledged as having a major impact on the effectiveness of the software development process, Sommerville et al. have developed a requirements maturity model. However, research has shown that the measurement process within Sommerville’s model is ambiguous, and implementation of his requirements maturity model leads to confusion. Hence, the objective of our research is to propose a new RE maturity measurement framework (REMMF) based on Sommerville’s model and to provide initial validation of REMMF. The main purpose of proposing REMMF is to allow us to more effectively measure the maturity of the RE processes being used within organisations and to assist practitioners in measuring the maturity of their RE processes. In order to evaluate REMMF, two organisations implemented the measurement framework within their IT divisions, provided us with an assessment of their requirements process and gave feedback on the REMMF measurement process. The results show that our measurement framework is clear, easy to use and provides an entry point through which the practitioners can effectively judge the strengths and weakness of their RE processes. When an organisation knows where it is, it can more effectively plan for improvement.

A requirements engineering environment within a tightly integrated SDE

This paper describes the outside functionality of an RE environment within an integrated software development environment. Furthermore, an integrator tool for the transition to software system architecture modelling is presented. The tools discussed are editors, analysers, executors, monitors, and integration tools of different characteristics for horizontal integration (within RE) and vertical integration (to architecture modelling). All tools are tightly integrated and work incrementally, therefore allowing different forms of construction and modification processes and giving substantial support.     

An evaluation of methods for prioritizing software requirements

This article describes an evaluation of six different methods for prioritizing software requirements. Based on the quality requirements for a telephony system, the authors individually used all six methods on separate occasions to prioritize the requirements. The methods were then characterized according to a number of criteria from a user's perspective. We found the analytic hierarchy process to be the most promising method, although it may be problematic to scale-up. In an industrial follow-up study we used the analytic hierarchy process to further investigate its applicability. We found that the process is demanding but worth the effort because of its ability to provide reliable results, promote knowledge transfer and create consensus among project members.     

A requirements engineering framework for cross-organizational ERP systems

The development of cross-organizational enterprise resource planning (ERP) solutions is becoming increasingly critical to the business strategy of many networked companies. The major function of cross-organizational ERP solutions is to coordinate work in two or more organizations. However, how to align ERP application components and business requirements for coordination and cooperation is hardly known. This paper reports on the outcomes of applying a coordination theory perspective to an analysis of the ERP misalignment problem. We present a conceptual framework for analyzing coordination and cooperation requirements in inter-organizational ERP projects. The framework makes explicit the undocumented built-in assumptions for coordination and cooperation that may have significant implications for the ERP adopters and incorporates a library of existing coordination mechanisms supported by modern ERP systems. We use it to develop a proposal for how to achieve a better alignment between ERP implementations and supported business coordination processes in inter-organizational settings. We report on some early assessments of the implications of our framework for practicing requirements engineers. Both our framework and library rest on a literature survey and the first author’s experience with ERP implementation. In future empirical research, we will further validate and refine our framework.     

Relationship analysis in requirements engineering

This research addresses a major shortcoming in todays requirements analysis techniques—the lack of a rigorous and comprehensive process to explicitly capture the relationship structure of the problem domain. Whereas other analysis techniques lightly address the relationship discovery process, relationship analysis (RA) is a systematic, domain-independent analysis technique focusing exclusively on a domains relationship structure. This paper describes RAs taxonomy of relationship types and corresponding brainstorming questions for eliciting the relationship structure from a domain expert. A preliminary case study analysis of online bookstores using RA as well as a formal experiment have both confirmed RAs effectiveness in helping the analyst produce significantly higher quality requirements. RA should become an invaluable tool for analysts, irrespective of the software engineering approach taken during systems analysis.     

A conceptual framework for requirements engineering

A framework for assessing research and practice in requirements engineering is proposed. The framework is used to survey state of the art research contributions and practice. The framework considers a task activity view of requirements, and elaborates different views of requirements engineering (RE) depending on the starting point of a system development. Another perspective is to analyse RE from different conceptions of products and their properties. RE research is examined within this framework and then placed in the context of how it extends current system development methods and systems analysis techniques.     

Scenario advisor tool for requirements engineering

This study investigates the usefulness of a scenario advisor tool which was built to help requirements engineers to generate sufficient sets of scenarios in the domain of socio-technical systems. The tool provides traceability between scenario models and requirements and helps to generate new scenarios and scenario variations. Through two series of evaluation sessions, we found that the scenario advisor tool helped users to write more sound scenarios without any domain knowledge, and to generate more variations on existing scenarios by providing specific scenario-generation hints for each scenario component. The tool should improve the reliability of requirements elicitation and validation.     

Scenario-based requirements analysis techniques for real-time software systems: a comparative evaluation

One of the most critical phases of software engineering is requirements elicitation and analysis. Success in a software project is influenced by the quality of requirements and their associated analysis since their outputs contribute to higher level design and verification decisions. Real-time software systems are event driven and contain temporal and resource limitation constraints. Natural-language-based specification and analysis of such systems are then limited to identifying functional and non-functional elements only. In order to design an architecture, or to be able to test and verify these systems, a comprehensive understanding of dependencies, concurrency, response times, and resource usage are necessary. Scenario-based analysis techniques provide a way to decompose requirements to understand the said attributes of real-time systems. However they are in themselves inadequate for providing support for all real-time attributes. This paper discusses and evaluates the suitability of certain scenario-based models in a real-time software environment and then proposes an approach, called timed automata, that constructs a formalised view of scenarios that generate timed specifications. This approach represents the operational view of scenarios with the support of a formal representation that is needed for real-time systems. Our results indicate that models with notations and semantic support for representing temporal and resource usage of scenario provide a better analysis domain.H. Saiedian is a member of the Information & Telecommunication Technology Center at the University of Kansas. His research was partially supported by a grant from the National Science Foundation (NSF).     

A market-driven requirements engineering process: Results from an industrial process improvement programme

In market-driven software evolution, the objective of a requirements engineering process include the envisioning and fostering of new requirements on existing packaged software products in a way that ensures competitiveness in the marketplace. This paper describes an industrial, market-driven requirements engineering process which incorporates continuous requirements elicitation and prioritisation together with expert cost estimation as a basis for release planning. The company has gained a measurable improvement in delivery precision and product quality of their packaged software. The described process will act as a baseline against which promising new techniques can be evaluated in the continuation of the improvement programme.     

Understanding the effects of requirements volatility in software engineering by using analytical modeling and software process simulation

This paper introduces an executable system dynamics simulation model developed to help project managers comprehend the complex impacts related to requirements volatility on a software development project. The simulator extends previous research and adds research results from an empirical survey, including over 50 new parameters derived from the associated survey data, to a base model. The paper discusses detailed results from two cases that show significant cost, schedule, and quality impacts as a result of requirements volatility. The simulator can be used as an effective tool to demonstrate the complex set of factor relationships and effects related to requirements volatility.     

Naming the pain in requirements engineering: A design for a global family of surveys and first results from Germany

ContextFor many years, we have observed industry struggling in defining a high quality requirements engineering (RE) and researchers trying to understand industrial expectations and problems. Although we are investigating the discipline with a plethora of empirical studies, they still do not allow for empirical generalisations.ObjectiveTo lay an empirical and externally valid foundation about the state of the practice in RE, we aim at a series of open and reproducible surveys that allow us to steer future research in a problem-driven manner.MethodWe designed a globally distributed family of surveys in joint collaborations with different researchers and completed the first run in Germany. The instrument is based on a theory in the form of a set of hypotheses inferred from our experiences and available studies. We test each hypothesis in our theory and identify further candidates to extend the theory by correlation and Grounded Theory analysis.ResultsIn this article, we report on the design of the family of surveys, its underlying theory, and the full results obtained from Germany with participants from 58 companies. The results reveal, for example, a tendency to improve RE via internally defined qualitative methods rather than relying on normative approaches like CMMI. We also discovered various RE problems that are statistically significant in practice. For instance, we could corroborate communication flaws or moving targets as problems in practice. Our results are not yet fully representative but already give first insights into current practices and problems in RE, and they allow us to draw lessons learnt for future replications.ConclusionOur results obtained from this first run in Germany make us confident that the survey design and instrument are well-suited to be replicated and, thereby, to create a generalisable empirical basis of RE in practice.     

An operational model for structuring the requirements generation process

Product quality is directly related to how well that product meets the customers needs and intents. Therefore, the ability to capture customer requirements correctly and succinctly is paramount. Unfortunately, within most software development frameworks requirements elicitation, recording and evaluation are some of the more ill-defined and least structured activities. To help address such inadequacies, we propose a requirements generation model (RGM) that (a) decomposes the conventional requirements analysis phase into sub-phases which focus and refine requirement generation activities, (b) bounds and structures those activities to promote a more effective generation process, and (c) implements a monitoring methodology to assist in detecting deviations from well-defined procedures intended to support the generation of requirements that meet the customers intent. The RGM incorporates lessons learned from a preliminary study that concentrated on identifying where and how miscommunication and requirements omission occur. An industry study (also reported in this paper) attests to the effectiveness of the RGM. The results of that study indicate that the RGM helps (a) reduce the late discovery of requirements, (b) reduce the slippage in milestone completion dates, and (c) increase customer and management satisfaction levels.