Ebba Þóra Hvannberg

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Life-long learning is a key issue for our knowledge society. With social software systems new heterogeneous kinds of technology enhanced informal learning are now available to the life-long learner. Learners outside of learning institutions now have access to powerful social communities of experts and peers who are together forging a new web 2.0. This paper(More)
Research on heuristic evaluation in recent years has focused on improving its effectiveness and efficiency with respect to user testing. The aim of this paper is to refine a research agenda for comparing and contrasting evaluation methods. To reach this goal, a framework is presented to evaluate the effectiveness of different types of support for structured(More)
Effectiveness of Heuristic Evaluation (HE) has severely been challenged. The present study investigated two strategies for improving the effectiveness of HE: Selection of usability guidelines (Gerhardt-Powals' cognitive engineering principles vs. Nielsen's heuristics); Provision of support and training. We also examined various strategies for estimating the(More)
Existing defect classification schemes are mainly used to characterize software defects. A few of them are specifically applicable to usability problems, but they have not been validated and their reliability has been assessed in a limited way. The aim of this study is to evaluate comprehensively the Classification Usability Problems (CUP) scheme. First,(More)
User effect in terms of influencing the validity and reliability of results derived from standard usability tests has been studied with different approaches during the last decade, but inconsistent findings were obtained. User effect is further complicated by other confounding variables. With the use of various computational models, we analyze the extent of(More)
The aim of this paper is twofold (i) comparing the effectiveness of two evaluation methods, namely heuristic evaluation and usability testing, as applied to an experimental version of the UNIVERSAL Brokerage Platform (UBP), and (ii) inferring implications from the empirical findings of the usability test. Eight claims derived from previous research works(More)
Defect classification can improve product quality and motivate process improvement. Several defect classification schemes have been developed and used with good results in software development. This paper describes the design and test of a defect classification scheme that specifically extracts information from usability problems. We describe the attributes(More)
Social software is used widely in organizational knowledge management and professional learning. The PROLEARN network of excellence appreciates the trend of lowering the barriers between knowledge and learning management strategies for organizations and individuals. But, companies should not underestimate the needs for systematic support based on sound(More)
Observing students writing specification in UML and Z has motivated the work presented in this paper. There is a need to add formal specification to diagrammatic notations such as UML and there is even a greater requirement to examine where in the software life cycle Z specifications are most useful. The Z language allows us to use abstraction in software(More)
Programmers of sequential and parallel computers share the objective of developing fast, reliable programs as efficiently as possible. Already, considerable effort has been made to develop tools and techniques for sequential computers. Several approaches have been devised to meet the parallel programming challenge. Sequential languages have been adapted for(More)