7,005 research outputs found

    Information dynamics: Temporal behavior of uncertainty measures

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    We carry out a systematic study of uncertainty measures that are generic to dynamical processes of varied origins, provided they induce suitable continuous probability distributions. The major technical tool are the information theory methods and inequalities satisfied by Fisher and Shannon information measures. We focus on a compatibility of these inequalities with the prescribed (deterministic, random or quantum) temporal behavior of pertinent probability densities.Comment: Incorporates cond-mat/0604538, title, abstract changed, text modified, to appear in Cent. Eur. J. Phy

    An Introduction to Ontology

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    Analytical philosophy of the last one hundred years has been heavily influenced by a doctrine to the effect that one can arrive at a correct ontology by paying attention to certain superficial (syntactic) features of first-order predicate logic as conceived by Frege and Russell. More specifically, it is a doctrine to the effect that the key to the ontological structure of reality is captured syntactically in the ‘Fa’ (or, in more sophisticated versions, in the ‘Rab’) of first-order logic, where ‘F’ stands for what is general in reality and ‘a’ for what is individual. Hence “f(a)ntology”. Because predicate logic has exactly two syntactically different kinds of referring expressions—‘F’, ‘G’, ‘R’, etc., and ‘a’, ‘b’, ‘c’, etc.—so reality must consist of exactly two correspondingly different kinds of entity: the general (properties, concepts) and the particular (things, objects), the relation between these two kinds of entity being revealed in the predicate-argument structure of atomic formulas in first-order logic

    Development of a new scale to measure ambiguity tolerance in veterinary students

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    The ability to cope with ambiguity and feelings of uncertainty is an essential element of professional practice. Research with physicians has identified that intolerance of ambiguity or uncertainty is linked to stress and some authors have hypothesised that there could be an association between intolerance of ambiguity and burnout (e.g. Cooke et al 2013). We describe the adaptation of the TAMSAD (Tolerance of Ambiguity in Medical Students and Doctors) scale for use with veterinary students. Exploratory factor analysis supports a unidimensional structure for the Ambiguity tolerance construct. Although internal reliability of the 29 item TAMSAD scale is reasonable (α = 0.50), an alternative 27 item scale (drawn from the original 41 items used to develop TAMSAD) shows higher internal reliability for veterinary students (α = 0.67). We conclude that there is good evidence to support the validity of this latter TAVS (Tolerance of Ambiguity in Veterinary students) scale to study ambiguity tolerance in veterinary students

    Modelling potential movement in constrained travel environments using rough space-time prisms

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    The widespread adoption of location-aware technologies (LATs) has afforded analysts new opportunities for efficiently collecting trajectory data of moving individuals. These technologies enable measuring trajectories as a finite sample set of time-stamped locations. The uncertainty related to both finite sampling and measurement errors makes it often difficult to reconstruct and represent a trajectory followed by an individual in space-time. Time geography offers an interesting framework to deal with the potential path of an individual in between two sample locations. Although this potential path may be easily delineated for travels along networks, this will be less straightforward for more nonnetwork-constrained environments. Current models, however, have mostly concentrated on network environments on the one hand and do not account for the spatiotemporal uncertainties of input data on the other hand. This article simultaneously addresses both issues by developing a novel methodology to capture potential movement between uncertain space-time points in obstacle-constrained travel environments

    Responsible Research and Innovation between \u201cnew governance\u201d and fundamental rights

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    This chapter frames RRI as an emerging governance approach in the EU regulatory context. We argue that reference to fundamental rights makes RRI a distinctive approach to responsibility compared to other existing paradigms and that human rights, in particular those laid down in the Charter of Fundamental Rights of the European Union, are not necessarily a constraint but can instead be a catalyst of innovation. Eventually we maintain that a governance framework based on the complementarity between legal norms and voluntary commitments might successfully combine the respect of fundamental rights with the openness and flexibility of the innovation process

    Probabilistic representations in perception: Are there any, and what would they be?

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    Nick Shea’s Representation in Cognitive Science commits him to representations in perceptual processing that are about probabilities. This commentary concerns how to adjudicate between this view and an alternative that locates the probabilities rather in the representational states’ associated “attitudes”. As background and motivation, evidence for probabilistic representations in perceptual processing is adduced, and it is shown how, on either conception, one can address a specific challenge Ned Block has raised to this evidence

    Antecipação na tomada de decisĂŁo com mĂșltiplos critĂ©rios sob incerteza

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    Orientador: Fernando JosĂ© Von ZubenTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia ElĂ©trica e de ComputaçãoResumo: A presença de incerteza em resultados futuros pode levar a indecisĂ”es em processos de escolha, especialmente ao elicitar as importĂąncias relativas de mĂșltiplos critĂ©rios de decisĂŁo e de desempenhos de curto vs. longo prazo. Algumas decisĂ”es, no entanto, devem ser tomadas sob informação incompleta, o que pode resultar em açÔes precipitadas com consequĂȘncias imprevisĂ­veis. Quando uma solução deve ser selecionada sob vĂĄrios pontos de vista conflitantes para operar em ambientes ruidosos e variantes no tempo, implementar alternativas provisĂłrias flexĂ­veis pode ser fundamental para contornar a falta de informação completa, mantendo opçÔes futuras em aberto. A engenharia antecipatĂłria pode entĂŁo ser considerada como a estratĂ©gia de conceber soluçÔes flexĂ­veis as quais permitem aos tomadores de decisĂŁo responder de forma robusta a cenĂĄrios imprevisĂ­veis. Essa estratĂ©gia pode, assim, mitigar os riscos de, sem intenção, se comprometer fortemente a alternativas incertas, ao mesmo tempo em que aumenta a adaptabilidade Ă s mudanças futuras. Nesta tese, os papĂ©is da antecipação e da flexibilidade na automação de processos de tomada de decisĂŁo sequencial com mĂșltiplos critĂ©rios sob incerteza Ă© investigado. O dilema de atribuir importĂąncias relativas aos critĂ©rios de decisĂŁo e a recompensas imediatas sob informação incompleta Ă© entĂŁo tratado pela antecipação autĂŽnoma de decisĂ”es flexĂ­veis capazes de preservar ao mĂĄximo a diversidade de escolhas futuras. Uma metodologia de aprendizagem antecipatĂłria on-line Ă© entĂŁo proposta para melhorar a variedade e qualidade dos conjuntos futuros de soluçÔes de trade-off. Esse objetivo Ă© alcançado por meio da previsĂŁo de conjuntos de mĂĄximo hipervolume esperado, para a qual as capacidades de antecipação de metaheurĂ­sticas multi-objetivo sĂŁo incrementadas com rastreamento bayesiano em ambos os espaços de busca e dos objetivos. A metodologia foi aplicada para a obtenção de decisĂ”es de investimento, as quais levaram a melhoras significativas do hipervolume futuro de conjuntos de carteiras financeiras de trade-off avaliadas com dados de açÔes fora da amostra de treino, quando comparada a uma estratĂ©gia mĂ­ope. AlĂ©m disso, a tomada de decisĂ”es flexĂ­veis para o rebalanceamento de carteiras foi confirmada como uma estratĂ©gia significativamente melhor do que a de escolher aleatoriamente uma decisĂŁo de investimento a partir da fronteira estocĂĄstica eficiente evoluĂ­da, em todos os mercados artificiais e reais testados. Finalmente, os resultados sugerem que a antecipação de opçÔes flexĂ­veis levou a composiçÔes de carteiras que se mostraram significativamente correlacionadas com as melhorias observadas no hipervolume futuro esperado, avaliado com dados fora das amostras de treinoAbstract: The presence of uncertainty in future outcomes can lead to indecision in choice processes, especially when eliciting the relative importances of multiple decision criteria and of long-term vs. near-term performance. Some decisions, however, must be taken under incomplete information, what may result in precipitated actions with unforeseen consequences. When a solution must be selected under multiple conflicting views for operating in time-varying and noisy environments, implementing flexible provisional alternatives can be critical to circumvent the lack of complete information by keeping future options open. Anticipatory engineering can be then regarded as the strategy of designing flexible solutions that enable decision makers to respond robustly to unpredictable scenarios. This strategy can thus mitigate the risks of strong unintended commitments to uncertain alternatives, while increasing adaptability to future changes. In this thesis, the roles of anticipation and of flexibility on automating sequential multiple criteria decision-making processes under uncertainty are investigated. The dilemma of assigning relative importances to decision criteria and to immediate rewards under incomplete information is then handled by autonomously anticipating flexible decisions predicted to maximally preserve diversity of future choices. An online anticipatory learning methodology is then proposed for improving the range and quality of future trade-off solution sets. This goal is achieved by predicting maximal expected hypervolume sets, for which the anticipation capabilities of multi-objective metaheuristics are augmented with Bayesian tracking in both the objective and search spaces. The methodology has been applied for obtaining investment decisions that are shown to significantly improve the future hypervolume of trade-off financial portfolios for out-of-sample stock data, when compared to a myopic strategy. Moreover, implementing flexible portfolio rebalancing decisions was confirmed as a significantly better strategy than to randomly choosing an investment decision from the evolved stochastic efficient frontier in all tested artificial and real-world markets. Finally, the results suggest that anticipating flexible choices has lead to portfolio compositions that are significantly correlated with the observed improvements in out-of-sample future expected hypervolumeDoutoradoEngenharia de ComputaçãoDoutor em Engenharia ElĂ©tric

    Indeterminacy-aware prediction model for authentication in IoT.

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    The Internet of Things (IoT) has opened a new chapter in data access. It has brought obvious opportunities as well as major security and privacy challenges. Access control is one of the challenges in IoT. This holds true as the existing, conventional access control paradigms do not fit into IoT, thus access control requires more investigation and remains an open issue. IoT has a number of inherent characteristics, including scalability, heterogeneity and dynamism, which hinder access control. While most of the impact of these characteristics have been well studied in the literature, we highlighted “indeterminacy” in authentication as a neglected research issue. This work stresses that an indeterminacy-resilient model for IoT authentication is missing from the literature. According to our findings, indeterminacy consists of at least two facets: “uncertainty” and “ambiguity”. As a result, various relevant theories were studied in this work. Our proposed framework is based on well-known machine learning models and Attribute-Based Access Control (ABAC). To implement and evaluate our framework, we first generate datasets, in which the location of the users is a main dataset attribute, with the aim to analyse the role of user mobility in the performance of the prediction models. Next, multiple classification algorithms were used with our datasets in order to build our best-fit prediction models. Our results suggest that our prediction models are able to determine the class of the authentication requests while considering both the uncertainty and ambiguity in the IoT system
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