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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
Rytz construction and geometry of singular value decomposition
No full textU radu promatramo geometriju dekompozicije matrice odnosno linearnog operatora po singularnim vrijednostima (skraćeno SVD).
Singularne vrijednosti matrice su kvadratni korijeni svojstvenih vrijednosti hermitski simetrične, pozitivno definitne matrice . Ključna je činjenica da se dijagonalizira u ortonormiranoj bazi te da djelovanje na svojstvene vektore od čuva ortogonalnost. U SVD matrica tipa faktorizira se kao umnožak tri matrice, od kojih su one vanjske ortogonalne/unitarne, a srednja je jednakog tipa kao te sadrži dijagonalnu podmatricu sa singularnim vrijednostima na dijagonali. Geometrijski ta faktorizacija znači kompoziciju, redom, izometrije kojom se prelazi u ortonormiranu bazu svojstvenih vektora od , zatim skaliranja po smjerovima tih vektora te završno još jedne izometrije.
U euklidskoj ravnini SVD se primjenjuje na bijektivnu afinu transformaciju i njezino djelovanje na jediničnu kružnicu. Slika je elipsa, određena bilo kojim parom konjugiranih promjera kao slikom para ortogonalnih promjera kružnice. Rytzovom konstrukcijom dobivaju se glavne osi elipse, a duljine poluosi elipse jednake su singularnim vrijednostima operatora . Druga geometrijska primjena SVD odnosi se na kosu aksonometriju, to jest paralelnu projekciju euklidskog prostora na ravninu, u kojoj je zadana slika jedne ortonormirane baze prostora. Postupkom analognim prethodnom konstruiraju se projekcije prividne i stvarne konture jedinične sfere.In this thesis we examine the geometry of the singular values decomposition (SVD) of a matrix or a linear operator. The singular values of the matrix are the square roots of the eigenvalues of the Hermitian symmetric, positive definite matrix . The key fact is that is diagonalized in an orthonormal basis and the action of on the eigenvectors of preserves orthogonality. In SVD, matrix of type is factorized as a product of three matrices, of which the outer one are orthogonal/unitary, and the middle one is of the same type as and contains a diagonal submatrix with singular values on the diagonal. Geometrically, this factorization means the composition, respectively, of an isometry, which is used for transition to the orthonormalized base of eigenvectors of , then scaling along the directions of these vectors, and finally another isometry.
In the Euclidean plane, SVD is applied to the bijective affine transformation and its action on the unit circle. The image is an ellipse, defined by any pair of conjugate diameters as the image of a pair of orthogonal diameters of a circle. The main axes of the ellipse are obtained by the Rytz construction, and the lengths of the semi-axes of the ellipse are equal to the singular values of the operator . Another geometric application of SVD refers to oblique axonometry, that is, the parallel projection of Euclidean space onto a plane, in which the image of an orthonormal base of space is given. Using a similar procedure, projections of the apparent and real contours of the unit sphere are constructed
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
Rytz construction and geometry of singular value decomposition
No full textU radu promatramo geometriju dekompozicije matrice odnosno linearnog operatora po singularnim vrijednostima (skraćeno SVD).
Singularne vrijednosti matrice su kvadratni korijeni svojstvenih vrijednosti hermitski simetrične, pozitivno definitne matrice . Ključna je činjenica da se dijagonalizira u ortonormiranoj bazi te da djelovanje na svojstvene vektore od čuva ortogonalnost. U SVD matrica tipa faktorizira se kao umnožak tri matrice, od kojih su one vanjske ortogonalne/unitarne, a srednja je jednakog tipa kao te sadrži dijagonalnu podmatricu sa singularnim vrijednostima na dijagonali. Geometrijski ta faktorizacija znači kompoziciju, redom, izometrije kojom se prelazi u ortonormiranu bazu svojstvenih vektora od , zatim skaliranja po smjerovima tih vektora te završno još jedne izometrije.
U euklidskoj ravnini SVD se primjenjuje na bijektivnu afinu transformaciju i njezino djelovanje na jediničnu kružnicu. Slika je elipsa, određena bilo kojim parom konjugiranih promjera kao slikom para ortogonalnih promjera kružnice. Rytzovom konstrukcijom dobivaju se glavne osi elipse, a duljine poluosi elipse jednake su singularnim vrijednostima operatora . Druga geometrijska primjena SVD odnosi se na kosu aksonometriju, to jest paralelnu projekciju euklidskog prostora na ravninu, u kojoj je zadana slika jedne ortonormirane baze prostora. Postupkom analognim prethodnom konstruiraju se projekcije prividne i stvarne konture jedinične sfere.In this thesis we examine the geometry of the singular values decomposition (SVD) of a matrix or a linear operator. The singular values of the matrix are the square roots of the eigenvalues of the Hermitian symmetric, positive definite matrix . The key fact is that is diagonalized in an orthonormal basis and the action of on the eigenvectors of preserves orthogonality. In SVD, matrix of type is factorized as a product of three matrices, of which the outer one are orthogonal/unitary, and the middle one is of the same type as and contains a diagonal submatrix with singular values on the diagonal. Geometrically, this factorization means the composition, respectively, of an isometry, which is used for transition to the orthonormalized base of eigenvectors of , then scaling along the directions of these vectors, and finally another isometry.
In the Euclidean plane, SVD is applied to the bijective affine transformation and its action on the unit circle. The image is an ellipse, defined by any pair of conjugate diameters as the image of a pair of orthogonal diameters of a circle. The main axes of the ellipse are obtained by the Rytz construction, and the lengths of the semi-axes of the ellipse are equal to the singular values of the operator . Another geometric application of SVD refers to oblique axonometry, that is, the parallel projection of Euclidean space onto a plane, in which the image of an orthonormal base of space is given. Using a similar procedure, projections of the apparent and real contours of the unit sphere are constructed
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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