1,721,037 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
Topological central extensions of parahoric subgroups of SL(n,D).
No full textTopological central extensions play a role in several areas of mathematics, e.g., in consideration of the congruence subgroup problem and of automorphic forms of fractional weight. The D in the title is a division algebra over a non-archimedean local field k. This thesis examines the topological central extensions of any parahoric sub-group P of SL\sb{n}(D), where SL\sb{n}(D) is the set of n x n matrices with entries in D and of reduced norm one. Topological central extensions of P are determined by the second continuous cohomology group H\sp2(P,\IR/\doubz). The main theorem of this thesis shows the p-primary component of H\sp2(P,\IR/\doubz) is a finite, cyclic p-group. Using the main theorem and Theorem 1.3 due to G. Prasad, I show the p-primary part of H\sp2(P,\IR/\doubz) is isomorphic to the p-primary component of H\sp2(SL\sb{n}(D),\IR/\doubz). I also compute the prime to p component of H\sp2(P,\IR/\doubz).PhDMathematicsPure SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/129777/2/9624638.pd
Gamma factors of certain supercuspidal representations.
No full textIt is an important task to properly define gamma-factors for representations of reductive groups over p-adic fields. Since general representations of such groups are not easily accessible at present, investigation upon more easily accessible supercuspidal representations of depth zero should guide us in search of general theory. In this paper, we compute gamma-factors for certain classical groups. The result is a sum over a finite group of Lie type, which may be called a non-abelian Gauss sum. In some cases, we prove that the gamma-factor we computed are the right answer expected by the local Langlands conjecture.PhDMathematicsPure SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/131692/2/9929865.pd
Weighted cohomology of arithmetic groups.
No full textIn this thesis the equivalence of two cohomology theories attached to an arithmetic group is shown and some applications are made. The first is the recently introduced weighted cohomology of Goresky, Harder, and MacPherson, defined via a complex of sheaves on the reductive Borel-Serre compactification of the locally symmetric space attached to the arithmetic group. It replaces the intersection cohomology of the Baily-Borel compactification when the locally symmetric space is not Hermitian. The second is weighted L\sb2 cohomology introduced in work of Franke on the computation of cohomology by automorphic forms. In the Hermitian case the former reduces (in a particular case) to the intersection cohomology of the Baily-Borel compactification and the latter reduces to the L\sb2 cohomology, recovering the Looijenga and Saper-Stern theorem (Zucker's conjecture). (This uses in a crucial way results of Looijenga and so is not a new proof of the conjecture.) The equivalence is proven by a local argument on the reductive Borel-Serre compactification which is a 'desingularization' (only topologically) of the Baily-Borel compactification. Both cohomology theories are interpreted via complexes of sheaves and then an explicit local quasiisomorphism is constructed between them using results of Borel and Franke and the geometry of the compactification. The equivalence is actually with a version of L\sb2 cohomology that is modified to be locally finite dimensional. Using this result the weighted cohomology groups, which are topological invariants, are interpreted as Lie algebra cohomology of spaces of automorphic forms for the arithmetic group. This interpretation is combined with spectral information on the modified L\sb2 spaces to make the connexion with usual L\sb2 cohomology. The first application is to Goresky and MacPherson's topological approach to Arthur's Lefschetz formula for Hecke operators. Another application is a formula for the local cohomology of the Baily-Borel compactification; this formula was established in special cases in different settings earlier. The methods are applied to study L\sb{p} cohomology and similar identities with weighted cohomology groups are proven.PhDMathematicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/105129/1/9635580.pdfDescription of 9635580.pdf : Restricted to UM users only
Some arithmetical applications of integration on reductive groups.
No full textIn this thesis, we investigate several applications of integration with respect to certain arithmetically defined Haar measures on reductive algebraic groups. Over local fields, we obtain a characteristic-free proof of a recent theorem of B. H. Gross comparing a measure defined using Bruhat-Tits theory with the Euler-Poincare measure. Over global fields, we show that Weil's conjecture on Tamagawa numbers holds for simply-connected quasi-split groups in characteristic p.PhDMathematicsPure SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132181/2/9959802.pd
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
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