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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
Paleoceanographic implication of the Eocene-Oligocene calcareous nannofossils from ODP Sites 711 and 748 in the Indian Ocean
No full textAn Eocene-Oligocene calcareous nannofossil biostratigraphic framework for Ocean Drilling Program (ODP) Site
748 in the southern Indian Ocean is established, which provides a foundation for this and future quantitative biogeographic studies. This biostratigraphic analysis, together with quantitative nannofossil data, enables a reinterpretation of the preliminary magnetostratigraphy and a new placement for magnetic Subchron CBN in the
lowermost Oligocene.
Calcareous nannofossil species diversity is low at Site 748 relative to lower latitude sites, with about 13 taxa in
the middle Eocene, gradually decreasing to about 6 in the late Oligocene. There is, however, no apparent mass
extinction at any stratigraphic level. Similarly, no mass extinctions were recorded at or near the Eocene/Oligocene
boundary at Site 711 in the equatorial Indian Ocean. Species diversity at the equatorial site is significantly higher
than at Site 748, with a maximum of 39 species in the middle Eocene and a minimum of 14 species in the late
Oligocene. The abundance patterns of nannofossil taxa are also quite different at the two sites, with chiasmoliths,
Isthmolithus recurvus, and Reticulofenestra daviesii abundant and restricted to the high-latitude site and Coccolithus
formosus, discoasters, and sphenoliths abundant at the equatorial site but impoverished at the high-latitude
site. This indicates a significant latitudinal biogeographic gradient between the equatorial site and the high-latitude
site in the Indian Ocean for the middle Eocene-Oligocene interval.
The abundance change of warm-water taxa is similar to that of species diversity at Site 711. There is a general
trend of decreasing abundance of warm-water taxa from the middle Eocene through the early Oligocene at Site 711,
suggesting a gradual cooling of the surface waters in the equatorial Indian Ocean. The abundance of warm-water
taxa increased in the late Oligocene, in association with an increase in species diversity, and this may reflect a
warming of the surface waters in the late Oligocene.
An abrupt increase in the abundance of cool-water taxa (from —20% to over 90%) occurred from 36.3 to 35.9 Ma at
high-latitude Site 748. Coincident with this event was a ~ 1.0 %o positive shift in the δ1 8θ value of planktonic foraminifers
and the occurrence of ice-rafted debris. This abrupt change in the nannofossil population is a useful biostratigraphic event
for locating the bottom of magnetic Subchron C13N in the Southern Ocean. The sharp increase in cool-water taxa coeval
with a large positive shift in δ'8O values suggests that the high-latitude surface waters drastically cooled around 36.3-35.9
Ma. The temperature drop is estimated to be 4°C or more at Site 748 based on the nannofossil population change relative
to the latitudinal biogeographic gradient established in the South Atlantic Ocean during previous studies. Consequently,
much of the δ1 8θ increase at Site 748 appears to be due to a temperature drop in the high latitudes rather than an
ice-volume signal. The ~0.1%e δ1 8θ increase not accounted for by the temperature drop is attributed to an ice-volume
increase of 4.6 × I03 km3, or 20% the size of the present Antarctic ice sheet
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
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