1,721,171 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
Essai de caracterisation phytoecologique des formations herbacees paturees de Grande-Terre (Guadeloupe)
No full textDans le but de caractériser les types de prairies naturelles (ou « savanes ») de la Grande-Terre (Guadeloupe), 350 relevés ont été effectués, selon un plan d’échantillonnage stratifié en fonction de la pluviométrie et de la profondeur du sol. Outre les espèces présentes (et leurs abondances), 61 variables ont été notées pour chaque relevé. La technique d’interprétation utilisée est celle des profils écologiques, conduisant à la constitution de groupes écologiques plurifactoriels d’espèces. Il est montré que les variables du milieu les plus explicatives ressortissent au macroclimat (pluviométrie surtout) et aux caractères édaphiques et topographiques. Les communautés végétales mises en évidence sont caractérisées par leur composition en groupes écologiques, et par leurs conditions de milieu. Une présentation synthétique des résultats est faite grâce à l’Analyse Factorielle des Correspondances (AFC). Les types de savanes ainsi caractérisés sont en outre évalués par le calcul des moyennes des valeurs pastorales des relevés constitutifs. Les « paysages prairiaux » des petites régions de Grande-Terre sont décrits.In order to characterize the types of natural meadows (or "savannas") in Grande-Terre (Guadeloupe) - fig. 1 -, 350 samples were taken. Sampling was stratified according to annual rainfall and soil depth. Besides the species present (and their abundance), 61 factors were noted for each sample. The results were interpreted by the ecological series method, which gives plurifactorial ecological species groups (tables 1a and 16). The most explanatory environmental factors were macroclimate (mainly rainfall), and edaphic and topographic characteristics. The plant communities defined (tables 3a and 3b) were characterized by their composition in ecological species groups (table 2), and by their prevalent environmental conditions. These entities could be represented synthetically by Factor Analysis of Correspondences (AFC) (fig. 2 through 5). The pasture types resulting from this study were evaluated by computing the average pasture value of the component samples, according to rough quality indices of species. A "pastoral landscape" of the regions of Grande-Terre was accordingly described (table 4)
A spatial covariance model with a single wave effect and a finite range
No full textInternational audienceWe propose a new spatial covariance model with a single wave effect and a finite range. The construction of this model is based on a radial kernel composed of two concentric spheres and the finite range enables us to obtain an exact simulation from the circulant embedding method. This model responds to the lack of efficient covariance functions to model patterns characterized by concentration areas surrounded by gaps. We compare the single wave model to other existing hole effect models such as the Bessel model, the damped cosine model and the cardinal sine mode
Modelisation de la dynamique de repartition de l'azote chez un jeune arbre fruitier pendant la phase de croissance exponentielle. I. Estimation de parametres
No full textL’arbre fruitier est analysé comme étant un système ouvert représenté par un ensemble de compartiments anatomiques (racines, tronc, rameaux, feuilles) dont les variables descriptives, d’état ou de commande, sont en évolution dynamique. A partir de cette représentation schématique de la réalité, il est proposé un modèle d’organisation de ces compartiments qui permet de rendre compte de la dynamique des transferts d’azote dans l’arbre. Cette dynamique est basée sur une équation régissant les débits d’azote entre les organes végétaux et qui dépend de 2 termes principaux : le premier traduisant la disponibilité de cet azote (teneur en N de la source) et le second l’intensité de la demande (accroissement en matière sèche des puits). Le sous-modèle, correspondant à cette dynamique, comprend 3 paramètres qui sont, chacun, associés à un organe, source d’un débit d’azote. Les valeurs de ces paramètres peuvent être interprétées comme traduisant le caractère plus ou moins important de réserve des compartiments correspondants. L’étude de sensibilité réalisée confirme la nécessité structurelle des 3 paramètres. Son ajustement à un ensemble de données expérimentales conduit à un écart-type résiduel de l’ordre de 0,08 g de N pour des masses mesurées variant de 0,1 à 2 g selon les organes végétaux et les dates de mesures.The fruit tree has been analysed as an open system formed ol anatomical compartments (roots, trunk, shoots, leaves) whose state or command variables are in dynamic evolution. On the basis of this scheme, a model of compartment organization is proposed which shows up the dynamics of nitrogen transfers in the tree. These dynamics are based on an equation determining the rate of these nitrogen transfers between plant parts. This equation is made up of 2 main variables : one showing the availability of nitrogen at source, which is represented by nitrogen content (DM basis), and the other showing the degree of demand made by the sink, which is represented by the increase in dry matter. The sub-model of nitrogen transfers contains 3 parameters each of which is associated with a plant part, acting as a source of nitrogen. The fit of the parameters can be interpreted as showing the relative importance of the corresponding compartments as nitrogen reserves. A sensitivity study showed the structural necessity of these 3 parameters. The model has been fitted to experimental data. It leads to a mean residual error of 0.08 g N which is to be compared with measured amounts of nitrogen between 0.1 and 2 g, according to anatomical compartments and time
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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