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
Sugar Beet Cyst Nematode (Heterodera schachtii Schmidt): Identification and Antagonists
No full textSugar beet is listed within the top ten most important crops in the world. The paleobotanic data
suggest the sea beet was grown in the ancient times, while the beets with swollen roots were
cultivated in the Middle Ages in Europe. Sugar beet cyst nematode Heterodera schachtii is an
invasive organism causing high economic loss to sugar beet worldwide. The fundamental steps in
control of harmful organisms in plant protection and food safety are grounded on rapid detection
of the causative agent and its proper identification. The prompt reaction before obvious
symptoms occur can prevent devastating consequences. To confirm the identity of an invasive
organism, the process demands the combination of identification techniques, such as morphology
and molecular characterization. The phylogeography of available H. schachtii populations, based
on matching historical data with phylogenetic analyses of the ITS rRNA region pinpointed a
possible place of origin of the European H. schachtii populations. A next step is the
determination of natural antagonists of nematodes. Due to the long persistence of the parasite in
soil, cysts harbor a large number of bacteria and fungi, the presence of which can lead to cyst
death and population decline. Bacteria, fungi and other antagonists are an inevitable part of the
soil ecosystem and are also part of those mechanisms in nature that limit the excessive number of
invasive organisms and return ecological system to its stable equilibrium, acceptable for the
existence of humans as well as micro and macrobiota on Earth
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
- …
