1,720,987 research outputs found
Macroecological theory and the analysis of species richness gradients
No full textExplaining regional and global scale patterns of biodiversity has occupied naturalists since before the dawn of modern ecology (Hawkins 2001). This endeavor has accelerated recently, sparked in part by the emergence of macro ecology as a discipline (Ricklefs and Schluter 1993; Brown 1995); by substantial increases in the availability of tools for manipulating, analyzing, and graphically displaying data on species’ geographical distributions (e.g., Geographical Information Systems software); and by the increasingly urgent need to prioritize regions for conservation on a global scale (see Roberts et al. 2002; Hughes, Bellwood, and Connolly 2002; Worm et al. 2005 for marine examples). This recent work has confirmed that many very different taxa exhibit similar species richness gradients. In the marine realm, for instance, species richness frequently exhibits a hump- shaped pattern, with species richness decreasing with latitudinal and longitudinal distance from the Indo-Australian Archipelago (e.g., fig. 11.1; also see Stehli and Wells 1971; Crame 2000; Ellison 2002; Roberts et al. 2002), although many taxa also exhibit a secondary hotspot in the Caribbean (Stehli and Wells 1971; Duke Lo, and Sun 2002; Roberts et al. 2002). Bathymetric gradients oft en are also hump- shaped, peaking at intermediate depths (Piñeda and Caswell 1998; Rex et al. 2005; but see Gray 2001). Exceptions to these general rules have also been identified. For instance, marine counter examples to the latitudinal diversity gradient include macroalgae (Kerswell 2006), fish parasites (Rohde 1998), seals and seabirds (Proches 2001)
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
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
Sea urchin (Eucidaris) quadrat counts at twelve sites in the Galápagos Islands in 2016-2017
No full textDataset: Sea urchin density Galápagos IslandsSea urchin (E. galapagensis) densities showed high variability across twelve study sites in the Galápagos Islands in 2016-2017. Sea urchin densities ranged from a low of 0.17 individuals per 0.25 square meter quadrat at the Pinzon site to a maximum of 7.7 individuals per quadrat at the Champion site in January 2016.
For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/872905NSF Division of Ocean Sciences (NSF OCE) OCE-162386
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
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