1,721,014 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
Precision Tests of Gravity From Gravitational Wave Propagation in Curved Spacetime
No full textThe recent detection of gravitational waves (GWs) in 2015 opened a completely new way to constrain cosmology and gravity. In this thesis, I start by reviewing how gravitational waves emitted by compact binaries may be used as distance indicators in the context of general relativity. I then discuss scalar-tensor modifications of gravity motivated as dark-energy models and how those can affect gravitational waves and evade local constraints from the Solar System via so-called screening mechanisms. In particular, I present how the effective distance probed by standard sirens may be affected by scalar-tensor modifications of gravity. I show how this distance is only affected by local properties of the source and of the observer, which are assumed and constrained to live in screened environments. To do so, I present a formalism to study the evolution of the amplitude of scalar and tensor waves which propagate in a generically curved background spacetime, which allows to account for inhomogeneities which appear in the Universe, as well as in the background scalar field, necessary to account for screening. I present a way to diagonalize the system of equations of motion for the scalar and tensor degrees of freedom and find that interactions are always negligible, although the argument depends on the scalar phase velocity. Next, I focus on subluminal scalar waves interacting with matter fields and discuss scalar Cherenkov radiation from high-energy cosmic rays, which may slow them down. I show how this effect is negligible if the effective field theory (EFT) of gravity is designed to explain cosmic acceleration but how it may be significant if the EFT is applicable at higher energy scales. Finally, I challenge the geometric optics approximation in a general relativistic GW lensing scenario. I show how in certain configurations, a point-like lens can affect the transport of the polarization of the gravitational waves in such a way that may be confused with a smoking gun signature of deviations from general relativity. I discuss the probability to generate significant effective non-tensorial polarizations in a realistic Universe and find that the probability is small for the expected binary black hole merger rates, thereby confirming the robustness of the geometric optics approximation
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
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 cosmological constant problem
No full textAn additional variation of the Einstein-Hilbert action with respect to the Planck mass provides a constraint on the average Ricci scalar that prevents vacuum energy from gravitating. Consideration of the evolution of the inhomogeneous matter distribution in the Universe with evaluation of the averaging constraint on disconnected matter cells that ultimately form isolated gravitationally bound structures yields a backreaction effect that self-consistently produces the cosmological constant of the background. A uniform prior on our location in the formation of these isolated structures implies a mean expectation for the present cosmological constant energy density parameter of ΩΛ=0.704, giving rise to a late-time acceleration of the cosmic expansion and a coincident current energy density of matter
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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