1,720,985 research outputs found
A consistency theorem for regular conditional distributions
No full textLet be a measurable
space, a sub--field and a random probability measure on , . In various frameworks, one looks for a probability on such that is a regular conditional
distribution for given for all . Conditions for such a to exist are given. The conditions are quite simple when is a compact Hausdorff space equipped with the Borel or the Baire -field (as well as under similar assumptions). Applications to Gibbs measures and Bayesian statistics are given as well
Semiparametric M-quantile regression for count data
No full textLung cancer incidence over 2005–2010 for 326 Local Authority Districts in England is investigated by ecological regression. Motivated from mis-specification of a Negative Binomial additive model, a semiparametric Negative Binomial M-quantile regression model is introduced. The additive part relates to those univariate or bivariate smoothing components, which are included in the model to capture nonlinearities in the predictor or to account for spatial dependence. All such components are estimated using penalized splines. The results show the capability of the semiparametric Negative Binomial M-quantile regression model to handle data with a strong spatial structure
Effects of cutaneous negative pressure application on perforator artery flow in healthy volunteers: a preliminary study
No full textBACKGROUND: The creation of skin flaps based on small perforator vessels is an increasingly popular procedure nowadays; the optimization of their blood supply enhances surgical success. This study evaluates the effects on the flowmetries of 7 days' negative pressure application on the skin surface overlying the muscle fascia emergence of periumbilical perforators of the deep inferior epigastric artery (DIEA). METHODS: Ten volunteer participants were enrolled. In each subject, one periumbilical perforator of the DIEA was identified on each side of the abdomen using an eco-color-Doppler. One of them was used as the control group, while the other (the study group) underwent 80 mm Hg negative pressure for 7 days. The flowmetries of both perforators were measured before and after the application of negative pressure wound therapy. RESULTS: After the application of negative pressure, randomly applied on the skin surface over one of the two selected periumbilical perforators, an increase in the flowmetries was observed in both groups of perforators (2.74 cm/s; p < 0.0001). The relative flowmetry increase in the control group was 9.55% (2.735 cm/s), while in the study group it was 44.03% (8.748 cm/s). CONCLUSION: The application of negative pressure system on the skin surface over the muscle fascia emergence of the selected periumbilical perforators showed an increase in flowmetry. Although this is a preliminary study, this simple and economical procedure before surgery could be usefully employed to increase the rate of success in microsurgical procedures
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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