1,720,958 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Estimation des paramètres des EDS : modèle de black et scholes
108 p. ; ill. ; 30 cmL'évolution des actifs financiers est essentiellement décrite par des processus continus, et plus particulièrement par des processus de diffusion log- normale. Ce mémoire développe les méthodes d'estimation des paramètres du modèle Black et Scholes ainsi que l'adaptation en finance. Nous présentons la théorie des probabilités et on introduit la notion d'estimation chapitre 1, la théorie des processus stochastiques chapitre 2 et la théorie générale d'évaluation d'options pour l'alternative stochastique chapitre 3. Le quatrième chapitre porte respectivement sur l'estimation des paramètres du modèle Black et Scholes par deux méthodes ; la méthodes discrète utilisant la fonction densité de transition du processus de diffusion, la seconde se base sur la fonction de densité du temps de première passage du processus à travers une borne constante et nous illustrons ensuite nos résultats par des applications numériques sur le cours de l'action Toyota MTR chapitre
Estimation des paramètres des EDS : modèle de black et scholes
108 p. ; ill. ; 30 cmL'évolution des actifs financiers est essentiellement décrite par des processus continus, et plus particulièrement par des processus de diffusion log- normale. Ce mémoire développe les méthodes d'estimation des paramètres du modèle Black et Scholes ainsi que l'adaptation en finance. Nous présentons la théorie des probabilités et on introduit la notion d'estimation chapitre 1, la théorie des processus stochastiques chapitre 2 et la théorie générale d'évaluation d'options pour l'alternative stochastique chapitre 3. Le quatrième chapitre porte respectivement sur l'estimation des paramètres du modèle Black et Scholes par deux méthodes ; la méthodes discrète utilisant la fonction densité de transition du processus de diffusion, la seconde se base sur la fonction de densité du temps de première passage du processus à travers une borne constante et nous illustrons ensuite nos résultats par des applications numériques sur le cours de l'action Toyota MTR chapitre
Variations on the Author
“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
We 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
We 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
We 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
Estimation of the parameters of the stochastic differential equations black-scholes model share price of gold
Problem statement: The estimation of the parameters is one of main problems of the dynamic models in many scientific fields and particularly in economics and finance. In this study, we examine the techniques of estimation of the parameters of the Black-Scholes model. These techniques are based on the function of probability. Approach: The two estimations are based on the likelihood function. The "discret" method considers the function of density of transition from the process of diffusion normal log. The second method proposes the estimate of the parameters of the model via the observation of the time of first passage of the process through a constant limit of which the density is known. Results: One treats an application of the share price of gold. Conclusion: A comparative study between both methods of estimations of the parameters and the forecast is give
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