1,721,142 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

    Variations on the Author

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    “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

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    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

    Comparative study on structural sensitivity of eigenvalue–based molecular descriptors

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    © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG part of Springer Nature. Structural sensitivity is one of the most important and the least investigated property of the topological molecular descriptors. This paper reports results on the structural sensitivity of graph energy, Estrada index, and resolvent energy on several series of catacondensed and pericondensed isomeric benzenoid hydrocarbons. Recently, a novel method for assessing the structural sensitivity of topological molecular descriptors was put forward, which is applied here. This algorithm consists of several different steps and it is based on Tanimoto index and Morgan circular fingerprints. It was found that graph energy, Estrada index, and resolvent energy exert similar structural sensitivity on catacondensed isomers. The graph energy showed the best performance on pericondensed molecules. Additionally, the sensitivities of these descriptors were tested on the catacondensed isomers with the increasing number of bays, coves, and fjords. It was revealed that these descriptors gradually change with the increasing number of these structural features. The Estrada index and resolvent energy perform similarly and in some cases with the same structural sensitivity. This may be attributed to the high correlation between them. The graph energy showed superiority over the Estrada index and resolvent energy on pericondensed isomers

    Dispelling the Myths Behind First-author Citation Counts

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    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

    Author Index

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    Odd-vertex-degree trees maximizing Wiener index

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    Wiener index is the oldest and one among the most investigated topological indices in mathematical chemistry and in related disciplines. Recently, Wiener index of odd–vertex–degree (ToddT^{odd}) trees has been investigated. In this paper, trees with second, third, ..., seventeenth maximal Wiener index are characterized.Publishe

    Atom-bond connectivity index versus Graovac-Ghorbani analog

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    The atom-bond connectivity index was introduced almost twenty years ago as an improvement of the well-known Randić index. Its mathematical properties and theory are well established and chemical usefulness confirmed in various research projects. On the other hand, recently introduced quantity that was named as second ABCABC index resembles to the original-one, but it is not validated anywhere as a molecular descriptor. Also its mathematical properties are examined to a limited extent. This paper is devoted to the comparison of these two topological invariants.Publishe
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