1,720,955 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
Methods for Summarizing and Imputing High-Frequency Digital Biomarkers in the Context of Longitudinal Data Analysis
No full textDigital biomarkers have the potential to aid early detection of cognitive decline, resulting in interventions that delay dementia onset. Digital biomarkers are measured at high frequencies, which increases opportunities for assessment of cognitive ability. Summarization of digital biomarkers helps to reduce computational burden or variance among values. However, the consequences of summarization processes are not statistically investigated, especially the potential bias in longitudinal data analysis. This dissertation will systematically investigate methods for summarization and imputation of high-frequency digital biomarker data. These methods are created in the context of longitudinal analysis of a binary cognitive outcome with digital biomarker predictors.
In Chapter 2, we discuss factors of high-frequency digital biomarker data that need to be considered when faced with a time granularity decision, defined as the frequency at which measurements are observed or summarized. It is important to find a balance between ease of analysis by condensing data and the integrity of the data, which is reflected in a chosen time granularity. Via simulation, we investigate the factors and examine how each affects the ability to detect the true, underlying digital biomarker pattern using root mean squared error. Then we apply our procedure to the Intelligent Systems for Assessing Aging Change (ISAAC) study, which involves longitudinal walking speed. The example sheds light on typical problems data present and how we can use the above factors in exploratory analysis to choose an appropriate time granularity.
In Chapter 3, we examine the process of simultaneously imputing and summarizing digital biomarker data. When analyzing the association of digital biomarker data and a lower-frequency outcome, we want to summarize biomarker data to match the outcome’s frequency while simultaneously imputing missing biomarker values. We define two methods for the imputation and summarization process: (1) Impute then Summarize, where we impute at the finest time granularity, then summarize, and (2) Summarize then Impute, where we summarize the biomarker then impute at the summary level. Via simulation, we assess two processes involving imputation of biomarkers for longitudinal analysis of a binary outcome. Our results show that accuracy of coefficient estimation depends on percent missing data, length of consecutive missing days, and the rate of trajectory change of the biomarkers. We apply these processes to the ISAAC study, and find that the odds of testing for mild cognitive impairment is negatively associated with increased walking speed.
In Chapter 4, we investigate simultaneous imputation of multiple, potentially correlated digital biomarkers, and association analysis of one biomarker with a longitudinal outcome. We build off the two methods in Chapter 3 using an updated regression model that incorporates information from additional biomarkers through random effects. Via simulation, we vary levels of correlation between digital biomarkers and percent missing values of each digital biomarker to examine the effect on imputed digital biomarker values and relative bias of coefficient estimates from longitudinal analysis. the coefficient estimate of the longitudinal analysis. Our results show increased correlation has the biggest effect on reducing relative bias, followed by increased number of digital biomarkers. We also found that at low correlation levels, an increase in percent missing values of other digital biomarkers results in the decreased in magnitude of relative bias. We apply our imputation methods to the ISAAC study with two and four digital biomarkers, and find that imputed values do not improve with additional digital biomarkers.PhDBiostatisticsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/176481/1/nwakim_1.pd
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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