1,721,000 research outputs found

    Alternative parameter learning schemes for monitoring process stability

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    In statistical process control, accurately estimating in-control (IC) parameters is crucial for effective monitoring. This typically requires a Phase I analysis to obtain estimates before monitoring commences. The traditional "fixed" estimate (FE) approach uses these estimates exclusively, while the "adaptive" estimate (AE) approach updates the estimates with each new observation. Such extreme criteria reflect the traditional bias-variance tradeoff in the framework of the sequential parameter learning schemes. This paper proposes an intermediate update rule that generalizes two ad hoc criteria for monitoring univariate Gaussian data, by giving a lower probability to parameter updates when an out-of-control (OC) situation is likely, therefore updating more frequently when there is no evidence of an OC scenario. The simulation study shows that this approach improves the detection power for small and early shifts, which are commonly regarded as a weakness of control charts based on fully online adaptive estimation. The paper also shows that the proposed method performs similarly to the fully adaptive procedure for larger or later shifts. The proposed method is illustrated by monitoring the sudden increase in ICU counts during the 2020 COVID outbreak in New York

    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

    Serum 25-hydroxyvitamin D concentration in Japanese Akita dogs: a survey

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    Low serum level of vitamin D has been linked to numerous diseases. The Akita breed of dog shows a high incidence of immune-mediated diseases such as uveodermatologic (UVD) syndrome and sebaceous adenitis (SA). Furthermore, in Japanese Akita dogs, skin depigmentation often appears after birth at different ages, in healthy dogs, and without any other symptoms. In humans poliosis is associated to low vitamin D level. The aim of this survey was to evaluate serum 25-hydroxyvitamin D (25(OH)D) levels in Japanese Akita dogs. One hundred and three Akita blood samples were collected for the 25(OH)D evaluation. Age, sex, current disease, presence and location of skin depigmentation, and diet were reported on a medical record. Based on history and clinical examination, dogs were classified according their health status as healthy (HE) or pathological (PA). The overall mean of 25(OH)D concentration was 82.42 ± 26.14 ng/mL, whereas the concentrations in the healthy dogs were significantly higher (84.90 ± 3.36 ng/mL) in comparison with the dogs with diseases (72.13 ± 4.09 ng/mL) (P < 0.01). In this study, the depigmented healthy dogs showed low level of 25(OH)D and very similar to the sick group. The appearance of depigmented areas associated with low levels of vitamin D could be considered as an alert sign in Akitas as well as in humans. However, clinical trials should also be carried out to establish whether vitamin D supplementation could be an effective preventive treatment to limit the onset of immune-mediated diseases in Japanese Akita dogs

    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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