1,720,955 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Essays on Economic Sentiment Dynamics and Asymmetric Multifractal Models of Financial Volatility
Full text linkIn the first chapter of the dissertation an estimation of the continuous-time Markov chain (CTMC) model of experts' sentiment index is considered in the case of incomplete data. Particularly, three estimation approaches based on a discrete-time sample are presented: the EM algorithm and two versions of the maximum likelihood estimation method. The first approach for the estimation of the considered model is iterative and leads to massive recursive computations of matrices. The most crucial part of the second and third approaches is the numerical computation of the matrix exponential of the intensity matrix. In particular, the second approach is based on the eigendecomposition of the intensity matrix and the corresponding well-known property of matrix exponential for such decomposition. In order to increase the effectiveness of the method in the third approach the fact that the intensity matrix has a lower Hessenberg form is used. All three approaches are based on numerical optimization using the nonlinear conjugate optimizer. The second chapter is dedicated to the development of the methods of calibration and estimation of the model belonging to the asset price class of models. Two variants of the generalization of the Markov Switching Multifractal (MSM) model, called the Asymmetric Markov-Switching Multifrequency, are considered. The modifications are aimed to reproduce such a phenomenon of asset returns as leverage effect. Other features of the model, namely the long memory stylized fact for different frequencies and degrees of persistence, the mean reversion of volatility, and the volatility clustering, are investigated and proven. The option pricing theory based on risk-neutral measure is developed for this model. In-sample and out-of-sample performance are tested
EEG analysis for Emotional Burnout detection
No full textA study of an EEG for identifying emotional burnout and an attempt to classify it has an importance to create a system that would safeguard people’s mental well-being. In certain medical surveys, people may give inaccurate answers while trying to rate their level of emotional burnout, which may cause difficulties in classifying their state. EEG, however, records one’s brain activity and provides the opportunity to reliably examine this factor, which could improve the recognition rate. Although the most common use of these models is to determine accuracy only in emotion detection, depression and stress diagnosis, this thesis will seek to demonstrate how these approaches can be tuned for the task of emotional exhaustion. The dataset consists of EEGs and survey results, which were collected at Kyiv Polytechnical University for the period 2010–2013. We experiment with different data preprocessing techniques and classification methods to find the best model for our data. Github with cod
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Pricing of European type options for Levy and conditionally Levy type models
No full textIn this thesis we consider two models for the computation of option prices. The first one is a generalization of the Black-Scholes model. In this generalization the volatility Sigma is not a constant. In the simplest case it changes at once at a certain time moment Tau. In some sense this is the conditionally Levy model. For this generalized Black-Scholes model have been theoretically obtained formulas for vanilla Call/Put option prices. Under the assumption of a good prediction of the parameter Sigma the obtained numerical results fit the real dara better than standard Black-Scholes model. Second model is an exponential Levy model, where a Levy process is the CGMY process. We use the finite-difference scheme for computations of option prices. As example we consider vanilla Call/Put, Double-Barrier and Up-and-out options. After the estimation of the parameters of the CGMY process by the method of moments we obtain options prices and calculate fitting error. This fitting error for the CGMY model is smaller than for the Black-Scholes model
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
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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