1,720,969 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Unimodal models to relate species to environment
No full textTo assess the impact of environmental change on biological communities knowledge about species-environment relationships is indispensable. Ecologists attempt to uncover the relationships between species and environment from data obtained from field surveys. In the survey, species are scored on their presence or their abundance at each of several sampling sites and environmental variables that ecologists believe to be important are measured.The research that led to this thesis aimed to unravel the assumptions required for the application of statistical methods that are popular among ecologists to analyse such data. From a statistical point of view, species data are difficult to analyse:- there are many species involved (10 - 500),- many species occur at a few sites only. So the data contain numerous zeroes,- relations between species and environmental variables are not linear, but unimodal: a plant, for example, preferably grows under for that species optimal moisture conditions and is encountered less frequently at drier or wetter sites. A mathematical model for a unimodal relationship is the Gaussian response model.Standard statistical methods such as linear regression, principal components analysis and canonical correlation analysis are often inappropriate for analysing species data because they are based on linear relationships. One of the methods that ecologists use instead is correspondence analysis. This thesis contributes to the understanding of the underlying response model.With correspondence analysis, species and sites are arranged to discover the structure in the data (ordination) and the arrangement is subsequently related to environmental variables. It is an indirect method to detect relations between species and environment, hence R.H. Whittaker's term "indirect gradient analysis".Correspondence analysis has been invented around 1935 but did not receive interest from ecologists before 1973 when M.O. Hill derived the technique once more as the repeated application of "weighted averaging" - a method that was familiar to ecologists ever since 1930. Weighted averaging has the advantage of being simple to apply. The method can be used for two different aims: (1) to estimate the optimum of a species for an environmental variable and (2) to estimate the value of an environmental variable at a site from known optima of the species present (calibration).In chapter 2, estimating optima by weighted averaging is compared with the results of non-linear regression on the basis of the Gaussian response model. Under particular conditions, both methods agree precisely. In other cases, weighted averaging gives a biased estimate of the optimum and non-linear regression is the method to be preferred. An additional advantage of non-linear regression is that it can also be used to fit response models with more than one environmental variable. In chapter 3, weighted averaging to estimate the value of an environmental variable is compared with calibration on the basis of the Gaussian response model. Also in this context the techniques are sometimes equivalent. Chapter 4 deals with correspondence analysis. It is shown that, under particular conditions, correspondence analysis approximates ordination on the basis of the Gaussian response model, which is computationally much more complicated.To detect relations, indirect methods have an important disadvantage. The impact of some environmental variables on the species composition can be so large that the impact of other interesting environmental variables may fail to be detected. This problem can be overcome by using non-linear regression, but with many species and environmental variables this is laborious. In chapter 5, a simpler "direct" method is proposed, canonical correspondence analysis. In chapter 6, canonical correspondence analysis turns out to be a multivariate extension of weighted averaging. The results can be displayed graphically. In chapter 7, an extension with "covariables" is discussed, which leads to partial canonical correspondence analysis. Chapter 7 also shows that Gaussian models and, hence, canonical correspondence analysis are relevant to the analysis of contingency tables.Chapter 8 describes a study to estimate ecological amplitudes of plant species with respect to Ellenberg's moisture scale from species data alone. The question that is addressed as well, is how consequent Ellenberg's moisture indicator values are.Finally, chapter 9 cross-tabulates various gradient-analysis techniques by the type of problem (regression, calibration, ordination, etc.) and the response model (linear or unimodal). Furthermore, improvements are proposed for detrended correspondence analysis. A computer program, named MOM is written which can perform most of the methods discussed.</TT
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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