13 research outputs found

    Foundations research in information retrieval inspired by quantum theory

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    In the information age information is useless unless it can be found and used, search engines in our time thereby form a crucial component of research. For something so crucial, information retrieval (IR), the formal discipline investigating search, can be a confusing area of study. There is an underlying difficulty, with the very definition of information retrieval, and weaknesses in its operational method, which prevent it being called a 'science'. The work in this thesis aims to create a formal definition for search, scientific methods for evaluation and comparison of different search strategies, and methods for dealing with the uncertainty associated with user interactions; so that one has the necessary formal foundation to be able to perceive IR as "search science". The key problems restricting a science of search pertain to the ambiguity in the current way in which search scenarios and concepts are specified. This especially affects evaluation of search systems since according to the traditional retrieval approach, evaluations are not repeatable, and thus not collectively verifiable. This is mainly due to the dependence on the method of user studies currently dominating evaluation methodology. This evaluation problem is related to the problem of not being able to formally define the users in user studies. The problem of defining users relates in turn to one of the main retrieval-specific motivations of the thesis, which can be understood by noticing that uncertainties associated with the interpretation of user interactions are collectively inscribed in a relevance concept, the representation and use of which defines the overall character of a retrieval model. Current research is limited in its understanding of how to best model relevance, a key factor restricting extensive formalization of the IR discipline as a whole. Thus, the problems of defining search systems and search scenarios are the principle issues preventing formal comparisons of systems and scenarios, in turn limiting the strength of experimental evaluation. Alternative models of search are proposed that remove the need for ambiguous relevance concepts and instead by arguing for use of simulation as a normative evaluation strategy for retrieval, some new concepts are introduced that can be employed in judging effectiveness of search systems. Included are techniques for simulating search, techniques for formal user modelling and techniques for generating measures of effectiveness for search models. The problems of evaluation and of defining users are generalized by proposing that they are related to the need for an unified framework for defining arbitrary search concepts, search systems, user models, and evaluation strategies. It is argued that this framework depends on a re-interpretation of the concept of search accommodating the increasingly embedded and implicit nature of search on modern operating systems, internet and networks. The re-interpretation of the concept of search is approached by considering a generalization of the concept of ostensive retrieval producing definitions of search, information need, user and system that (formally) accommodates the perception of search as an abstract process that can be physical and/or computational. The feasibility of both the mathematical formalism and physical conceptualizations of quantum theory (QT) are investigated for the purpose of modelling the this abstract search process as a physical process. Techniques for representing a search process by the Hilbert space formalism in QT are presented from which techniques are proposed for generating measures for effectiveness that combine static information such as term weights, and dynamically changing information such as probabilities of relevance. These techniques are used for deducing methods for modelling information need change. In mapping the 'macro level search' process to 'micro level physics' some generalizations were made to the use and interpretation of basic QT concepts such the wave function description of state and reversible evolution of states corresponding to the first and second postulates of quantum theory respectively. Several ways of expressing relevance (and other retrieval concepts) within the derived framework are proposed arguing that the increase in modelling power by use of QT provides effective ways to characterize this complex concept. Mapping the mathematical formalism of search to that of quantum theory presented insightful perspectives about the nature of search. However, differences between the operational semantics of quantum theory and search restricted the usefulness of the mapping. In trying to resolve these semantic differences, a semi-formal framework was developed that is mid-way between a programmatic language, a state-based language resembling the way QT models states, and a process description language. By using this framework, this thesis attempts to intimately link the theory and practice of information retrieval and the evaluation of the retrieval process. The result is a novel, and useful way for formally discussing, modelling and evaluating search concepts, search systems and search processes

    Evaluation of collision avoidance prototype head-up display interface for older drivers

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    Spatial and situational awareness could be decreased significantly under low visibility and adverse weather conditions. This could affect exponentially the reactions of the older drivers and increase dramatically their collision probability. To this end we developed a novel Head-Up Display interface that aims to reinstate the drivers’ vision which is predominantly hindered under these conditions. In particular the proposed interface entails symbolic representations of the lead vehicles and crucial road information, which effectively enhances driver’s vision. The proposed system was evaluated through a comparative study against the typical instrumentation panel. The evaluation results were overall in favour of the prototype interface which improved significantly the reaction times of the older drivers and decreased the collision occurrences

    On the Impact of User’s Computer Knowledge on Driving Simulation Test Results - HUD Simulation Case Study

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    Contemporary studies have focused on the development of rear collision avoidance or warning systems, in order to assist drivers during demanding driving situations and weather conditions. However, vehicle’s controllability through human decision-making is often impaired due to unambiguous interface designs. Our effort focuses on the development of a system that could complement human senses instead of replacing them, and improve users’ response times under adverse weather and traffic conditions. To this end we developed a prototype Head-Up Display (HUD) interface that could effectively convey the crucial information in a timely manner. The system’s effectiveness was validated using a custom simulation system and evaluated through trials with 40 users. In this paper we will present a succinct overview of the HUD system and we will investigate the correlation of users’ driving performance and their computer knowledge. The potential impact of computer familiarisation and simulation results will be analysed explicitly through the collision occurrence results derived from the comparative study of the HUD against the contemporary instrumentation panel

    Quantum interaction: 5th International Symposium, QI 2011, Aberdeen, UK, June 26-29, 2011, Revised Selected Papers (Lecture Notes in Computer Science / Theoretical Computer Science and General Issues)

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    This book constitutes the thoroughly refereed post-conference proceedings of the 5th International Symposium on Quantum Interaction, QI 2011, held in Aberdeen, UK, in June 2011. The 26 revised full papers and 6 revised poster papers, presented together with 1 tutorial and 1 invited talk were carefully reviewed and selected from numerous submissions during two rounds of reviewing and improvement. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, mechanics, social interaction, semantic space and information representation and retrieval
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