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Characteristics of pDILI. This table contains details of the 105 patients including the kinetics of pDILI, symptoms at presentation, initial regimen, management and overall outcome. (DOCX 20Â kb)

Software architectures are the conceptual tool to share information about key aspects of a software system and to enable reasoning about the principal, most fundamental, and often most difficult-to-change design decisions of the system. Studies of failed software systems give evidence that architecture drift, erosion or degradation is a prevalent problem in industrial practice. But a recent systematic literature review [9] indicates that research currently investigates compliance checking or inconsistency detection only. To advance research we need an open and grounded corpus of software architecture description - serving as a basis for more sophisticated studies beyond detection only. Such a corpus could enable (1) to evaluate new approaches, (2) to provide means for fixing degradation (when it occurs or a-posteriori), (3) to compare and benchmark approaches and, ultimately, (4) enable longitudinal studies in the field.

non-peer-reviewed Several authors have proposed information seeking as an appropriate perspective for studying software maintenance and evolution, and have characterized information seeking empirically in commercial software evolution settings. However, there is little research in the literature describing the information seeking behaviour of open source programmers, even though open source contexts would seem to exacerbate information seeking problems. That is, team members are typically delocalized from each other and they are often forced into asynchronous communication. This work reports on an empirical study that classifies Open-Source programmers??? information needs, as generated through open-coding of the questions that appear on their developer mailing lists. The study details the information sought by open source programmers on 3 different mailing lists over several years and characterizes the responses they obtained. In doing so, several interesting observations are made about the information these programmers seek, the likelihood that they will receive responses and the number of responses they are likely to get.

non-peer-reviewed Software architecture and its related documentation are acknowledged as some of the most important artefacts created during system design. However, often the implemented system diverges, over time, from the designed architecture. This phenomenon is called architectural drift and is either a result of inconsistent evolution of the system, or a failure to keep the architectural documentation up to date. A case study, performed at IBM, over two years showed how architectural drift can occur in small development teams over time. It suggested that even when approaches are in place to identify architectural drift, they may prove insufficient for subsequent removal of the drift, and some possible reasons for this were derived. Consequently, this document outlines the resultant design requirements for an approach to inhibit architectural drift, primarily by identifying it as, or before, it is introduced.

peer-reviewed Information-seeking has been recognized as a core subtask in software maintenance. While much of the research in this area attempts to identify the information sought by programmers, the work to date has been typically based on pre-defined information types limiting the potential for new information types to arise. Hence, this paper presents a small empirical study on open-source programmer mailing lists, to iteratively refine a schema of the information that programmers seek based exclusively on an analysis of these programmers??? naturalistic communication. Subsequently it places this schema in the context of the existing literature in the area. The analysis was undertaken on information requests in 288 emails, taken from 2 open source project mailing lists; The Java Bean Scripting Framework (BSF)[1] and the Java Development Tool (JDT)[2]. This work produced a preliminary schema of 3 main categories divided into 18 sub categories.

peer-reviewed This paper outlines the needs for careful empirical-design choices during the study of software practitioners. It does this by presenting a documented, but unpublished, in-vivo, empirical, group study. The study was initially conceived as an experiment but was subsequently overwhelmed by human and other factors. As a consequence, only more observational comments could be derived from the study. In this paper, the study is analyzed and discussed, as a means of illustrating the conflict that often exists between in-vivo empirical studies and the experimental paradigm.

peer-reviewed Modularity is one of the key features of the Object-Oriented (OO) paradigm. Low coupling and high cohesion help to achieve good modularity. Inheritance is one of the core concepts of the OO paradigm which facilitates modularity. Previous research has shown that the use of the friend construct as a coupling mechanism in C++ software is extensive. However, measures of the friend construct are scarse in comparison with measures of inheritance. In addition, these existing measures are coarse-grained, in spite of the widespread use of the friend mechanism. In this paper, a set of software metrics are proposed that measure the actual use of the friend construct, inheritance and other forms of coupling. These metrics are based on the interactions for which each coupling mechanism is necessary and sufficient. Previous work only considered the declaration of a relationship between classes. The software metrics introduced are empirically assessed using the LEDA software system. Our results indicate that the friend mechanism is used to a very limited extent to access hidden methods in classes. However, access to hidden attributes is more common.

peer-reviewed This paper introduces, and provides a cognitive basis for, a prototype meta-modeling process called ESCAPE. This process involves users explicitly stating their own model of an entity of interest, CAPturing an alternative or correct model of that entity and consequently re-Evaluating their own model. The paper shows the model???s implicit, but already well established, use in the software engineering domain. In particular, it focuses on empirical work carried out in Software Understanding and Architectural Recovery of large commercial software systems using the Reflexion modeling process, which embodies ESCAPE meta-modeling principles. Finally, it suggests several areas where ESCAPE meta-modeling could be beneficially applied in software engineerin

peer-reviewed Several authors have proposed information seeking as an appropriate perspective for studying software maintenance activities. However, there is little research in the literature describing holistic information-seeking models in this context. Additionally, in the one instance where an information-seeking model has been proposed, the empirical evidence presented in support of that model is extremely limited. This paper presents a small quasi-experiment that serves to further evaluate and refine this preliminary information-seeking model. Talkaloud data, generated by two professional programmers, engaged in real software maintenance activities, was captured and then coded. This evaluation largely validated the model but also suggested several important refinements. The study, its results and its impact on the information-seeking model are discussed in this paper.

non-peer-reviewed A large body of empirical work in the software comprehension area has focused on the cognitive processes that programmers undertake. However, as yet, little work exists on developing and assessing an encompassing framework within which one can compare the results from these software comprehension studies with one another. Several authors have proposed that Bloom???s taxonomy could provide such a framework and a lexical-analysis schema has been trialled to classify the data from empirical studies into this taxonomy. The schema is simple to apply but may result in ambiguity and reductionism. This paper proposes an alternative context-aware analysis schema. While such a schema undoubtedly consumes more effort, its value is illustrated by means of a pilot study, where its application is compared to that of the lexical-analysis schema.

peer-reviewed Identifying elements of existing software that are reused within a system may provide maintainers with valuable insights during system evolution. This paper evaluates an extension of software reconnaissance that can be used to analyse reuse across features in a system, as part of a component recovery process proposed in [18]. We illustrate and evaluate retrieval of reuse information in this fashion using a large, commercial ERP and warehousing application. Results suggest that the approach scales well in terms of reuse information across features in existing software, providing maintainers with a valuable new perspective on the software system in question.

peer-reviewed This paper presents a pilot study to test plans for an empirical study, which will compare the comprehensibility of two specifications: a formal specification and an informal specification. The two documents used in the pilot study implemented the same logic, namely a portion of the Irish Electoral system. The ???informal specification??? was taken directly from the legal definition of the count rules for Irish elections. A formal requirements specification language was not employed for the pilot study. In place of a formal requirements specification language, the java programming language was used. Our main motivation for using the java programming language is based on an empirical study carried out in [19].

peer-reviewed A commonly held belief is that the friend construct in C++ is a violation of encapsulation. However, little empirical analysis of its use has taken place to provide evidence to support this claim. This paper presents a study which assesses the design implications of including friendship in a system. A number of hypotheses are investigated based on previous work in this area by Counsell and Newson, [4]. Our initial findings suggest that classes declared as friends are coupling hotspots, that the more friends a class has the more protected and private members it will contain and that friendship is not used to access inherited protected members.

peer-reviewed Information seeking has been recognised as a core subtask in software maintenance. This paper reviews, merges, and adapts existing information seeking models for different domains to propose a non-linear information-seeking model for programmers involved in software maintenance. Talk-aloud data from two empirical studies of industrial programmers carrying out real software maintenance tasks is presented, to illustrate and validate (in part) this model.

n/a As development costs spiral upwards, creating ever more complex systems from scratch seems implausable. Component-based development offers the potential to tackle this issue through reuse. However, this approach must accommodate the exploitation of the embedded knowledge that already exists in non-component-based code. This paper proposes an extension to the software reconnaissance technique [15] that identi es reusable code within existing software systems. Once identi ed, the report shows how this code can be transformed for use within a component-based development paradigm.