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The charge statistic in type A via the affine Grassmannian
No full textWe give a new construction of Lascoux–Schützenberger's charge statistic in type A which is motivated by the geometric Satake equivalence. We obtain a new formula for the charge statistic in terms of modified crystal operators and an independent proof of this formula which does not rely on tableaux combinatorics
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
The Erweiterungssatz for the Intersection Cohomology of Schubert Varieties
No full textL'argomento di questa tesi è la Teoria Geometrica delle Rappresentazioni, nata nel 1980 con la dimostrazione dellla congettura di Kazhdan-Lusztig.
Nel primo capitolo sono introdotte le varietà considerate nel seguito: la varietà della bandiere, le varietà di Schubert e le loro
risoluzioni, le varietà di Bott-Samelson.
Nel capitolo 2 si discute l'algebra di Hecke di un gruppo di Coxeter e in particolare la sua base di Kazhdan-Lusztig.
Il capitolo 3 fornisce l'interpretazione geometrica dei polinomi di Kazhdan-Lusztig, costruendo una corrispondenza (o meglio una categorificazione) tra l'algebra di Hecke
e un'algebra costruita a partire dai complessi di coomologia d'intersezione delle varietà di Schibert. In particolare da questa interpretazione discendera la dimostrazione della positività dei polinomi di Kazhdan-Lusztig per i gruppi di Weyl.
Nel quarto capitolo si vede come questa corrispondenza
può essere definita anche in termini di una particolare classe
di bimoduli, detti bimoduli di Soergel.
Questo risultato è una delle conseguenze dell' ``Erweiterungssatz''. Nella seconda parte del capitolo è presente una dimostrazione di questo Teorema che si avvale di un teorema di localizzazione dovuto a V. Ginzburg.
Le appendici contengono alcune parti tecniche, che, se introdotte nel corpo principale della tesi, ne avrebbero appesantito la lettura ed
oscurato la linea argomentativa. In particolare:
l'appendice A contiene un riepilogo della categoria derivata dei complessi di fasci a coomologia costruibile, e dei principali funtori naturalmente definiti su questa.
Nell'appendice B sono introdotti, in modo abbastanza esteso, i fasci perversi e la coomologia d'intersezione.
L'appendice C contiene una breve introduzione alla teoria dei moduli misti di Hodge, sviluppata da Saito nei primi anni '90.
Questa teoria, assai complessa, individua un analogo per varietà complesse della teoria dei fasci -adici e del
conseguente formalismo dei pesi. Dalla teoria di Saito dipendono in modo cruciale
alcuni risultati esposti nei capitoli 3 e 4
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
Charges via the Affine Grassmannian
Get PDFWe give a new construction of Lascoux-Schützenberger\u27s charge statistic in type A which is motivated by the geometric Satake equivalence We obtain a new formula for the charge statistic in terms of modified crystal operators and an independent proof of this formula not relying on tableaux combinatorics.This version includes an expanded treatment of the first two chapters. The results on type A have been relocated to arXiv:2412.1056
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
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