Visual requirements analytics: a framework and case study

For many software projects, keeping requirements on track needs an effective and efficient path from data to decision. Visual analytics creates such a path that enables the human to extract insights by interacting with the relevant information. While various requirements visualization techniques exist, few have produced end-to-end value to practitioners. In this paper, we advance the literature on visual requirements analytics by characterizing its key components and relationships in a framework. We follow the goal–question–metric paradigm to define the framework by teasing out five conceptual goals (user, data, model, visualization, and knowledge), their specific operationalizations, and their interconnections. The framework allows us to not only assess existing approaches, but also create tool enhancements in a principled manner. We evaluate our enhanced tool support through a case study where massive, heterogeneous, and dynamic requirements are processed, visualized, and analyzed. Working together with practitioners on a contemporary software project within its real-life context leads to the main finding that visual analytics can help tackle both open-ended visual exploration tasks and well-structured visual exploitation tasks in requirements engineering. In addition, the study helps the practitioners to reach actionable decisions in a wide range of areas relating to their project, ranging from theme and outlier identification, over requirements tracing, to risk assessment. Overall, our work illuminates how the data-to-decision analytical capabilities could be improved by the increased interactivity of requirements visualization.     

The user–developer communication process: a critical case study

Abstract. Although user participation in systems development is widely believed to have positive impacts on user acceptance, it does not guarantee success and there is still much that we do not know about how and why user participation sometimes delivers positive benefits, but not always. Much of the prior research on user participation assumes that user–developer communication will ensure that the resulting system will be designed to meet users' needs and will be accepted by them. The nature and quality of the communication between users and developers, however, remains an understudied aspect of user participation. In this paper, we focus on the user–developer communication process. We propose a process model that delineates four stages of communication between users and software developers, and we argue that these stages must occur for user participation to lead to effective outcomes. To illustrate our model, we apply it to analyse a 'critical case study' of a software project that failed despite high levels of user involvement. We show that when 'communication lapses' occurred in several of the user–developer communication stages, developers failed to be informed regarding the underlying reasons that users avoided the system. Based on the insights from this case study, we advise researchers and practitioners how to leverage the potential benefits of user participation, rather than take them for granted.     

Formal models of communication services: a case study

Formal methods can play an important role in exploring new communication systems services. The telecommunications and data communications communities have long accepted the need for formally describing protocols, but only recently have they considered formally describing a service by abstracting specifications from a particular protocol that provides that service. Specifying a service at an abstract level meets two important needs: standardization and customization. The author presents a simplified atomic multicast as an example service and input/output automata for the formal model. He shows how to represent the service specification, a protocol, and implementations of that protocol. He also sketches how to prove the correctness of the protocol and implementation, that is, how to show that the specified service is actually provided     

The effects of multimedia communication technology on non-collocated teams: a case study

Collaborative teams are becoming increasingly important for industry, both within and across companies. There is a need for communication technology to support teams because many teams are non-collocated, or ‘virtual’. Two automotive supply chain teams were observed while they were experimenting with multimedia conferencing in order to determine what support non-collocated teams need and the potential effects of introducing technologies on their group processes. The observations included meeting recordings and other sources that show the organizational factors affecting teams. Working in teams requires very close collaboration. Communication technology can help teams if it is used to foster close and relatively informal person-to-person interaction. Organizational constraints on how the technology is introduced favour high-technology, specialpurpose installations, but teams can best be supported using relatively modest equipment with desktop access.     

The effects of multimedia communication technology on non-collocated teams: a case study

Collaborative teams are becoming increasingly important for industry, both within and across companies. There is a need for communication technology to support teams because many teams are non-collocated, or 'virtual'. Two automotive supply chain teams were observed while they were experimenting with multimedia conferencing in order to determine what support non-collocated teams need and the potential effects of introducing technologies on their group processes. The observations included meeting recordings and other sources that show the organizational factors affecting teams. Working in teams requires very close collaboration. Communication technology can help teams if it is used to foster close and relatively informal person-to-person interaction. Organizational constraints on how the technology is introduced favour high-technology, special-purpose installations, but teams can best be supported using relatively modest equipment with desktop access.     

Electronic bulletin boards: a case study of computer-mediated communication

Some observational data are presented on the use of an electronic bulletin board that serves a community of users within a single company. The major purposes for which this bulletin board is used are identified and some use patterns are given. Opportunities for human factors research on this technology are discussed.     

Generating requirements from systems models using patterns: a case study

Academic research has produced many model-based specification and analysis techniques, however, most organisations continue to document requirements as textual statements. To help bridge this gap between academic research and requirements practice, this paper reports an extension to the RESCUE process in which patterns for generating requirements statements from i* system models were manually applied to i* models developed for a complex air traffic control system. The paper reports the results of this application and describes them with examples, the benefits of the approach to the project, and ongoing research to implement these patterns in the REDEPEND modelling tool to make requirements engineers more productive. We review similar work on requirements modelling and expression, and compare our work to it to demonstrate the proposed advance in the state of the art. Finally the paper discusses future uses of requirements generation from model patterns in RESCUE.     

Speaker distinguishing distances: a comparative study

Speaker discrimination is a vital aspect of speaker recognition applications such as speaker identification, verification, clustering, indexing and change-point detection. These tasks are usually performed using distance-based approaches to compare speaker models or features from homogeneous speaker segments in order to determine whether or not they belong to the same speaker. Several distance measures and features have been examined for all the different applications, however, no single distance or feature has been reported to perform optimally for all applications in all conditions. In this paper, a thorough analysis is made to determine the behavior of some frequently used distance measures, as well as features, in distinguishing speakers for different data lengths. Measures studied include the Mahalanobis distance, Kullback-Leibler (KL) distance, T ² statistic, Hellinger distance, Bhattacharyya distance, Generalized Likelihood Ratio (GLR), Levenne distance, L ₂ and L _∞ distances. The Mel-Scale Frequency Cepstral Coefficient (MFCC), Linear Predictive Cepstral Coefficients (LPCC), Line Spectral Pairs (LSP) and the Log Area Ratios (LAR) comprise the features investigated. The usefulness of these measures is studied for different data lengths. Generally, a larger data size for each speaker results in better speaker differentiating capability, as more information can be taken into account. However, in some applications such as segmentation of telephone data, speakers change frequently, making it impossible to obtain large speaker-consistent utterances (especially when speaker change-points are unknown). A metric is defined for determining the probability of speaker discrimination error obtainable for each distance measure using each feature set, and the effect of data size on this probability is observed. Furthermore, simple distance-based speaker identification and clustering systems are developed, and the performances of each distance and feature for various data sizes are evaluated on these systems in order to illustrate the importance of choosing the appropriate distance and feature for each application. Results show that for tasks which do not involve any limitation of data length, such as speaker identification, the Kullback Leibler distance with the MFCCs yield the highest speaker differentiation performance, which is comparable to results obtained using more complex state-of-the-art speaker identification systems. Results also indicate that the Hellinger and Bhattacharyya distances with the LSPs yield the best performance for small data sizes.     

The role of domain knowledge in requirements elicitation via interviews: an exploratory study

Requirements elicitation is the first activity in the requirements engineering process. It includes learning, surfacing, and discovering the requirements of the stakeholders of the developed system. Various elicitation techniques exist to help analysts elicit the requirements from the different stakeholders; the most commonly used technique is the interview. Analysts may have domain knowledge prior to the elicitation process. Such knowledge is commonly assumed to have positive effects on requirements engineering processes, in that it fosters communication, and a mutual understanding of the needs. However, to a minor extent, some negative effects have also been reported. This paper presents an empirical study in which the perceived and actual effects of prior domain knowledge on requirements elicitation via interviews were examined. The results indicate that domain knowledge affects elicitation via interview in two main aspects: communication with the customers and understanding their needs. The findings provide insights as to both the positive and negative effects of domain knowledge on requirements elicitation via interview, as perceived by participants with and without domain knowledge, and show the existence of an actual effect on the course of the interviews. Furthermore, these insights can be utilized in practice to support analysts in the elicitation process and to form requirements analysis teams. They highlight the different contributions that can be provided by analysts with different levels of domain knowledge in requirements analysis teams and the synergy that can be gained by forming heterogeneous teams of analysts.     

User requirements of social media for the elderly: a case study in Taiwan

Numerous researchers have proposed website design norms that are suitable for the elderly. However, in the design of community platforms, elderly users were not considered in social media usage. Young and middle-aged people are the main targets in several social media platforms. To co-ordinate the digital lives of elderly users, the emphasis in this study was to determine the problems and to search for solutions. The real requirements and proper solutions for the elderly were integrated by analysing possible factors. This study is an anthropological user centred approach, to explore the verbal behaviour of senior citizens while they accessed Facebook. Facebook, which is a social media platform with a multilingual language interface, is currently used worldwide and served the purpose of an experimental base for this research. By determining the user environments that are suitable for the elderly, including web page accessibility, interface design and real social life transformation, this article proposes the factors for a social media website, the factors for the elderly to use social media platforms, a social media platform design that can be easily used by the elderly and design factors suitable for the elderly.     

Automotive behavioral requirements expressed in a specification pattern system: a case study at BOSCH

To allow an automatic formal analysis of requirements, the requirements have to be formalized first. However, logical formalisms are seldom accessible to stakeholders in the automotive context. Konrad and Cheng proposed a specification pattern system (SPS) represented in a restricted English grammar that can be automatically translated to logics, but looks like natural language. In this paper, we investigate whether this SPS can be applied to automotive requirements of BOSCH, in the sense that it is expressive enough to specify automotive behavioral requirements of BOSCH. We did a case study over 289 informal behavioral requirements taken from automotive BOSCH projects. We evaluated whether these requirements could be formulated in the SPS and whether the SPS has to be adapted to the automotive context. The case study strongly indicates that the SPS, extended with 3 further patterns, is suited to specify automotive behavioral requirements at BOSCH.     

Retrenching partial requirements into system definitions: a simple feature interaction case study

In conventional model-oriented formal refinement, the abstract model is supposed to capture all the properties of interest in the system, in an as-clutter-free-as-possible manner. Subsequently, the refinement process guides development inexorably towards a faithful implementation. However, refinement says nothing about how to obtain the abstract model in the first place. In reality developers experiment with prototype models and their refinements until a workable arrangement is discovered.Retrenchment is a formal technique intended to capture some of the informal approach to a refinable abstract model in a formal manner that will integrate with refinement. This is in order that the benefits of a formal approach can migrate further up the development hierarchy. The basic ideas of retrenchment are presented, and a simple telephone system feature interaction case study is elaborated. This illustrates not only how retrenchment can relate incompatible and partial models to a more definitive consolidated model during the development of the contracted specification, but also that the same formalism is applicable in a re-engineering context, where the subsequent evolution of a system may be partly incompatible with earlier design decisions. The case study illustrates how the natural method of composing retrenchments can give results that are too liberal in certain cases, and stronger laws of composition are derived for systems possessing suitable properties. It is shown that the methodology can encompass more ad hoc and custom-built techniques such as Zave's layered feature engineering approach to applications exhibiting a feature-oriented architecture (such as telephony).

An industrial case study in reconstructing requirements views

Requirements views, such as coverage and status views, are an important asset for monitoring and managing software development projects. We have developed a method that automates the process of reconstructing these views, and we have built a tool, ReqAnalyst, that supports this method. This paper presents an investigation as to which extent requirements views can be automatically generated in order to monitor requirements in industrial practice. The paper focuses on monitoring the requirements in test categories and test cases. In order to retrieve the necessary data, an information retrieval technique, called Latent Semantic Indexing, was used. The method was applied in an industrial study. A number of requirements views were defined and experiments were carried out with different reconstruction settings for generating these views. Finally, we explored how these views can help the developers during the software development process.

The case against a positivist philosophy of requirements engineering

Requirements engineering is a field with a heavy practical emphasis and for the most part is quite rightly unconcerned with philosophical reflection. However, there have been exceptions. Philosophical arguments are important because they can be used to powerful effect, facilitating explicit debate on views that may previously have been implicit, and shaping the direction of thought and research within the field. Several cases from both requirements engineering and software engineering have given prominence to the philosophy of positivism. This paper will outline arguments against such a view.

The role of social space requirements in ergonomics

This paper argues that, in addition to physical limitations inherent in the situation, account must be taken of social space requirements when designing systems in which people are placed in close proximity to each other. Personal space and territoriality are discussed to illustrate such problems.     

The role of emotion in computer-mediated communication: A review

It has been argued that the communication of emotions is more difficult in computer-mediated communication (CMC) than in face-to-face (F2F) communication. The aim of this paper is to review the empirical evidence in order to gain insight in whether emotions are communicated differently in these different modes of communication. We review two types of studies: (1) studies that explicitly examine discrete emotions and emotion expressions, and (2) studies that examine emotions more implicitly, namely as self-disclosure or emotional styles. Our conclusion is that there is no indication that CMC is a less emotional or less personally involving medium than F2F. On the contrary, emotional communication online and offline is surprisingly similar, and if differences are found they show more frequent and explicit emotion communication in CMC than in F2F.