1,721,055 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
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
Host interactions, pathology, economic impacts and management of the facultative parasitic weed Rhamphicarpa fistulosa
Get PDFRhamphicarpa fistulosa (Hochst.) Benth., is a facultative parasitic plant causing persistent weed problems in smallholder rice crops across Africa. It was first identified as a rice weed in the 1990's in West Africa. The objective of this review was to comprehensively inform the crop protection research community and extension services on the newly gained insights on R. fistulosa since the last review in 2014. Following a systematic literature search in Web of Science on papers published after September 2014, the cut-off date of the last review, the resulting publications are reviewed. Parasitizing Rhamphicarpa fistulosa plants gain considerably in biomass and reproductive output, compared to independently growing plants. The host incurs severe reductions in photosynthetic efficiency and biomass production. Host-plant assimilates primarily benefit parasite growth and reproduction. Rice yield losses caused by R. fistulosa infestations range from 24 to 73% depending on infestation density and cultivar. Annual crop losses in sub-Saharan Africa were estimated at 204,000 tons of milled rice, with associated annual economic losses of US $82M, affecting >140,000 rural households. Rice cultivars NERICA-L-40 and -31 were identified as resistant and high yielding under R. fistulosa infested conditions. Early sowing decreases R. fistulosa infection. Contrary to the obligate parasitic weed Striga spp., the facultative R. fistulosa is not controlled by fertilisers. The past decade of research generated valuable insights in the genetics, germination biology, environmental and ecological contexts, distribution and impacts on crop yields and economies, and disclosed feasible management options
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
On the interaction between weed and bird damage in rice
No full textWeeds and granivorous birds are the two major biotic constraints to rice production in sub-Saharan Africa. Anecdotal evidence advances the hypothesis that weedy fields attract granivorous birds to the extent that the joint weed × bird impact on crops is synergistic. We develop a theoretical model, based on experimental data, of the interaction between weed and bird damage to formally test this hypothesis. We observe that the response of bird-inflicted yield loss to weeds is unimodal and inverse-U-shaped. Bird-inflicted yield loss increases from 44% in weed-free conditions to a maximum of 55% at a critical weed infestation level of 20 g dry weight m−2. We conclude that the 11% increase in yield loss can be attributed to the synergistic interaction between weed and bird damage in rice. Our theory provides new insights into the analysis of the interaction between weeds and pests in general and supports a revision of currently accepted recommendations for weed management in rice. In areas where birds constitute an important production risk, it would be beneficial for rice farmers to remove those weeds that are tall enough to attract birds, even beyond the critical weed period
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