1,720,958 research outputs found

    Addressing uncertainty and complex data structures through Bayesian and classical approaches

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    Answering questions based on real-world data can pose considerable challenges to analysts. It often requires the use of data that are of questionable quality, exhibit high uncertainty, and may originate from multiple sources. Such data bear a high degree of complexity in their structure with respect to the underlying data-generating process. This cumulative thesis aims to address these issues in the context of selected research areas. The thesis is divided into two parts. The first part introduces the necessary methodology. The second part presents the four contributing articles. The methodological part provides an introduction chapter to statistical inference and probabilistic modeling by presenting Bayesian inference using Markov chain Monte Carlo as a general approach, and the generalized linear model (GLM) as a classical statistical method. Furthermore, the first part provides three chapters of methodological background in selected areas of research. The first area to be discussed is infectious disease modeling. The focus is on time-shifting operations that can be used to combine information from multiple time series. This lays the foundation for the first two contributions, which employ a Bayesian hierarchical approach to infectious disease modeling in the context of COVID-19 data. Next, an overview of measurement error theory is presented, followed by a discussion on how the Bayesian approach addresses these challenges. The third contribution demonstrates the flexibility of the Bayesian approach by applying it to data from the Wismut cohort, which presents considerable complexity and requires the use of multiple measurement error models. Finally, the last discussed chapter delves into the field of federated learning and privacy-preserving methods. The fourth contribution builds on the presented methodological background to develop an algorithm that is able to validate learned classification models through a GLM-based formulation of the ROC curve. An underlying theme of this thesis is the notion of uncertainty. In the Bayesian approach, uncertainty is encoded through the formulation of prior distributions and the overall probabilistic model, which inherently propagates and quantifies the uncertainty in a posterior distribution. The fourth contribution leverages the concept of uncertainty to preserve individual privacy by adding calibrated noise

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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