1,720,984 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
Effects of plant density on the performance of cowpea in Nigerian Savannas
No full textGrain yields of cowpea [Vigna unguiculata (L.) Walp.] in the Nigerian savannas are low even with the cultivation of improved varieties. The recommended spacing for cowpea is 75 × 20 cm with two seeds planted per stand. This corresponds to plant population of 133333 plants ha−1, which may not be sufficient for optimal cowpea yield. Field experiments were conducted to determine plant density effects on cowpea performance in the Northern Guinea and the Sudan savannas of Nigeria and also to determine if genotypes varied in their response to plant density. Four cowpea varieties with contrasting maturity duration were planted in single, double and triple rows on ridges spaced 75 cm apart to achieve corresponding densities of 133333, 266666 and 400000 plants ha−1, respectively. Plant densities of 266666 and 400000 plants ha−1 gave higher crop performance in terms of light interception, biomass production, yield and yield components for all cowpea varieties. Yield increases were related largely to increased pod and seed production but the effect of seed size on yield was relatively minor. Our results provide evidence that the current density of 133333 plants ha−1 used by farmers is not optimum for cowpea production. Smallholder farmers can increase cowpea grain and fodder yields if they use a density of 266666 plants ha−1 in cowpea cultivation. Further yield increases when cowpea is planted at 400000 plants ha−1 may not be sufficient to offset the cost of seed
Establishment of field trials in the Southern and northern Guinea Savannas of Nigeria. Monitoring of crop performance by smallholder farmers around the trial sites. Use of field data to validate predictive models for legume technology dissemination
No full textTrials were conducted under near-optimal conditions (moisture and nutrients non-limiting) via researcher managed conditions across various locations and sowing dates in rainy and dry season of 2016. Minimum data sets (MDS) for calibration of the models were collected across all locations. Phenological variables collected includes; number of days to first and full flower, first and full podding and physiological maturity. Yield data collected includes: number of pods per plant & meter square; pod weight per plot, number of seeds per pod, pod yield per hectare, seed yield per hectare, tops weight at harvest, pod yield per hectare and seed yield per hectare. Ten common cowpea varieties and seven common soybean varieties were planted as treatments in an RCBD with 3 replications
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
Understanding market participation choices and decisions of maize and cowpea farmers in northern Nigeria
No full textAlleviating poverty and reducing food insecurity have received close critical attention from many researchers in subSaharan Africa. Farmers' participation in agricultural markets has been seen as a potent strategy for improving their livelihoods. This paper applies econometrics to farm survey data from Bauchi and Kano states as major maize and cowpea growing areas hit by one of the most important root parasites known as Striga to determine the factors behind farmers' decisions about participation in the agricultural market and the volume of their output to be marketed. Relevant data was collected from 600 households in both states and results from the DoubleHurdle model indicated that price and nonprice constraints played significant roles in determining decisions on participation in the markets for both maize and cowpea. Household and total farm sizes, price and ease of transportation through access to motorized equipment were positively related to decision to participate in the maize market. However, the volume of sale of traded produce was influenced by locationspecific variable which underscores socioeconomic and populationrelated factors favoring market access that are present more in Kano than in Bauchi. Age of the household head and total farm size were significantly related to decision to participate in the cowpea market while results of the second stage of the model indicate that access to mobile phone and location variable affect positively the volume of cowpea sold. The role of price was conspicuous in both produce markets as the main incentive for households' participation. The paper concludes with policy implications aimed at providing better market opportunities to farmers thereby improving their welfare in northern Nigeria and other areas with similar socioeconomic and biophysical conditions in West Africa
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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