This thesis presents work on analytical reasoning with external representations (ERs) using problems similar to those used in the US GRE college-entrance examination. The work investigates the factors associated with effective ER use in situations where subjects select, construct and reason with their own ERs. Practically all previous work has tended to focus solely upon performance rather than process. In this thesis the emphasis is upon cognitive processes during the entire time-course of reasoning with ERs, from problem comprehension through to answer selection. A background to the work is provided by 2 comprehensive reviews of: 1.) previous research on ERs and reasoning and 2.) the cognitive and semantic properties of ERs. Results from three empirical studies are reported. The first study examined a large corpus of 'workscratchings' produced by subjects as they solved paper and pencil-based analytical reasoning problems under test conditions. The workscratching ERs showed great diversity between and within subjects and across a range of problems. They included lists, various kinds of table, set diagrams, node and arc diagrams, first-order and propositioned logic, plans and natural language. It is shown that problem-solving performance is related to the type of ER used in the solution. The second study utilised a computer-based system (switchERI). The system administered analytical reasoning problems and provided a. range of ER construction environments for the subject to choose and switch between. User-system interactions were recorded dynamically during problem solving. This methodology permitted microanalyses of the cognitive events at each stage during the time-course of problem solving. A process account of analytical reasoning with ERs is developed in which five major stages are identified - problem comprehension, ER selection, ER construction, read-off from the ER and answer selection/responding. A range of common slips and misconceptions are identified at each stage. The results show, inter alia, that subjects whose responses are consistent with their ERs perform better than subjects whose responses are inconsistent with their ERs even if the ER is partially incorrect. The data from the workscratching analysis and switchERI study informed the design of' switchERII, a second system. SwitchERII incorporates a. representation of the semantics of Euler's Circles, dynamically parses the user's representation and provides feedback and advice. A third study was conducted with the switchERII system. Few, if any, studies to date have attempted to relate subjects' prior knowledge of ER formalisms to their reasoning performance. Subjects' prior knowledge of ER formalisms was assessed in both switchER studies. It was observed that subjects' performance on representation interpretation tasks does not necessarily predict their performance in conditions where they select and construct their own representations. The reasons for the decoupling are discussed. Data from all three studies show that subjects often utilise multiple representations in their solutions, either concurrently or serially via. ER switching. Two distinctly different types of switching were observed. One kind ('thrashing') is associated with poorer performance and reflects less comprehensive prior knowledge, inability to select au appropriate ER and hazy problem comprehension. Judicious switching, on the other hand, is associated with high levels of problem comprehension and skilled matching of the ERs' properties to changing task demands. It is claimed that effective reasoning with ERs involves complex interactions between at least three factors: (a.) within-subject variables such as the subject's representational repertoire (prior knowledge) and representational modality preferences (cognitive style); (b.) skill at overcoming a variety of barriers to comprehension and an ability to discern the salient attributes and characteristics of different problem types and (c.) an understanding of the semantic and cognitive properties of graphical and non-graphical ERs coupled with an ability to match those properties to the problem's task demands. It is suggested that the role of externalisation in reasoning with ERs may be to facilitate the swapping of information between cognitive subsystems. A mechanism by which the use of diagrammatic ERs may facilitate self-explanation is also proposed. The thesis concludes with an argument in favour of a domain-independent 'ER curriculum'. It is suggested that direct instruction in the use of a range of ERs might equip students with wider representational repertoires and hence allow them more scope to indulge their representational preferences. Finally, several directions for future work are proposed. These include extending the representational semantics of switchERII, evaluating various types of system feedback and implementing a mechanism for checking for slips during read-off from ERs.

The surveillance of large sea areas typically involves  the analysis of huge quantities of heterogeneous data.  In order to support the operator while monitoring maritime traffic, the identification of anomalous behavior or situations that might need further investigation may reduce operators' cognitive load. While it is worth acknowledging that existing mining applications support the identification of anomalies, autonomous anomaly detection systems are rarely used for maritime surveillance. Anomaly detection is normally a complex task that can hardly be solved by using purely visual or purely computational methods. This thesis suggests and investigates the adoption of visual analytics principles to support the detection of anomalous vessel behavior in maritime traffic data. This adoption involves studying the analytical reasoning process that needs to be supported,  using combined automatic and visualization approaches to support such process, and evaluating such integration. The analysis of data gathered during interviews and participant observations at various maritime control centers and the inspection of video recordings of real anomalous incidents lead to a characterization of the analytical reasoning process that operators go through when monitoring traffic. These results are complemented with a literature review of anomaly detection techniques applied to sea traffic. A particular statistical-based technique is implemented, tested, and embedded in a proof-of-concept prototype that allows user involvement in the detection process. The quantitative evaluation carried out by employing the prototype reveals that participants who used the visualization of normal behavioral models outperformed the group without aid. The qualitative assessment shows that  domain experts are positive towards providing automatic support and the visualization of normal behavioral models, since these aids may reduce reaction time, as well as increase trust and comprehensibility in the system. Based on the lessons learned, this thesis provides recommendations for designers and developers of maritime control and anomaly detection systems, as well as guidelines for carrying out evaluations of visual analytics environments. / Maria Riveiro is also affiliated to Informatics Research Centre, Högskolan i Skövde / Information Fusion Research Program, Högskolan i Skövde

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 values to practitioners. In this dissertation, 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 supports both qualitatively and quantitatively. First, we evaluate our tool supports qualitatively 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 ending 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. Although many new visual analytics tools, techniques and methods are being developed, still there is a lack of understanding of how to evaluate the performance of such tools. We conducted an experiment to assess the performance (time and correctness) of our visual analytics tool support in solving requirements engineering tasks. Our study provides initial evidence and insights for visual analytics in requirements engineering and sheds light on many challenging open questions.

Introduction : l'aptitude à prendre des décisions est cruciale en médecine d'urgence. Notre étude avait pour objectif de mieux comprendre comment les médecins urgentistes prennent des décisions. Méthode : nous avons réalisé une étude qualitative basée sur des entretiens semi-structurés avec des urgentistes. Les entretiens ciblaient la gestion d'une situation d'urgence courante. Ils reposaient sur la visualisation d'une vidéo de l'activité enregistrée en perspective subjective située. Résultats : plusieurs résultats sont originaux. Nous avons en particulier montré le rôle central joué par l'intuition dans la prise de décisions. Par ailleurs, nous avons mis en évidence la façon dont les médecins urgentistes génèrent et hiérarchisent les hypothèses diagnostiques. Conclusion : l'usage d'une approche méthodologique innovante nous a permis de mieux comprendre la façon dont les urgentistes prennent des décisions, avec plusieurs implications pour la formation. / Introduction: the ability to makes decisions is a crucial skill in emergency medicine. Our study aimed at revealing how and when emergency physicians make decisions during the patients' initial management. Methods : we carried out a qualitative research project based on semistructured interviews with emergency physicians. The interviews concerned management of an emergency situation during routine medical practice. They were associated with viewing the video recording of emergency situations filmed in an “own-point-of-view” perspective. Résults : many results are original. Specifically, we showed the major role played by intuition in the decision making process. Moreover, we revealed the way emergency physicians generate and evaluate diagnostic hypotheses. Conclusions : the use of an innovative research method allowed us to better understand the way emergency physicians make decisions in their everyday practice. Our results are associated with several implications for medical education.

Abstract Background: Small businesses are vital for the welfare of a country. Yet, they have trou-ble obtaining external financing and these difficulties are gathered under the umbrella concept the “Financial Gap”. The most common source of fund-ing for small businesses is bank loan, why the availability of bank financing is a critical factor for their success. Today, 31% of all Swedish companies argue that they have finance problems and for half of these, the problem is to obtain a bank loan. Purpose: The purpose of the study is to describe and explain the Financial Gap as a relational concept. That is to say that the study will contribute to the understanding of the Financial Gap by focusing on the perspectives of both small businesses and banks interactively. Method: The study views the concept of the Financial Gap from a practical stand-point, assuming that it expresses its existence in the interaction between small businesses and banks. To pursue this view, the study takes on an Eth-nomethodological research approach. This approach is necessary in order to come close to and understand small businesses‟ and banks‟ everyday prac-tises. In-depth interviews are used for obtaining this deeper understanding of both parties. In addition, a questionnaire was sent out to small businesses in order to verify the information gathered in the interviews. Conclusion: On the basis of the study, the authors have developed an Interactive Model which describes their understanding of the Financial Gap. The members of small businesses and banks deal with information differently, which in turn is a result of how they approach ambiguity. When ambiguity is present, small firms settle with making decisions under uncertainty, whereas banks prefer to calculate on probabilities, why their decisions are considered being made under risk. The differences mentioned become visible in their deci-sion-making process, where small businesses act pursuant to a practical rea-soning whereas banks employ an analytical reasoning. Consequently, it leads to a clash when these two shall interact and function in a transaction as partners. The study concludes that the Financial Gap can be explained by small firms and banks speaking different languages when presenting the same reality.

<p><strong>Abstract </strong></p><p><strong>Background: </strong>Small businesses are vital for the welfare of a country. Yet, they have trou-ble obtaining external financing and these difficulties are gathered under the umbrella concept the “Financial Gap”. The most common source of fund-ing for small businesses is bank loan, why the availability of bank financing is a critical factor for their success. Today, 31% of all Swedish companies argue that they have finance problems and for half of these, the problem is to obtain a bank loan.</p><p><strong>Purpose: </strong><em>The purpose of the study is to describe and explain the Financial Gap as a relational concept. That is to say that the study will contribute to the understanding of the Financial Gap by focusing on the perspectives of both small businesses and banks interactively. </em></p><p><strong>Method: </strong>The study views the concept of the Financial Gap from a practical stand-point, assuming that it expresses its existence in the interaction between small businesses and banks. To pursue this view, the study takes on an Eth-nomethodological research approach. This approach is necessary in order to come close to and understand small businesses‟ and banks‟ everyday prac-tises. In-depth interviews are used for obtaining this deeper understanding of both parties. In addition, a questionnaire was sent out to small businesses in order to verify the information gathered in the interviews.</p><p><strong>Conclusion: </strong>On the basis of the study, the authors have developed an <em>Interactive Model </em>which describes their understanding of the Financial Gap. The members of small businesses and banks deal with information differently, which in turn is a result of how they approach ambiguity. When ambiguity is present, small firms settle with making decisions under uncertainty, whereas banks prefer to calculate on probabilities, why their decisions are considered being made under risk. The differences mentioned become visible in their deci-sion-making process, where small businesses act pursuant to a practical rea-soning whereas banks employ an analytical reasoning. Consequently, it leads to a clash when these two shall interact and function in a transaction as partners. The study concludes that the Financial Gap can be explained by small firms and banks speaking different languages when presenting the same reality.</p>