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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
Holomorphic maps between rings of power series
No full textDiese Arbeit besch\"{a}ftigt sich mit holomorphen Funktionen \Os_{d}^{p} \to \Os_{d}, wobei \Os_{d} f\"ur den Ring konvergenter Potenzreihen in Variablen stehe. In den ersten beiden Kapiteln werden die hierf\"ur notwendigen Konzepte aus Funktionalanalysis und Topologie erarbeitet. Die Darstellung \Os_{d} = \bigcup_{S \in \R_{+}^{d}} \ell^{\infty}(S) ergibt eine nat\"urliche Topologisierung von \Os_{d} als induktiven Limes, wobei der Banachraum aller Potenzreihen ist, f\"ur welche die gewichtete Supremumsnorm endlich ist. Es zeigt sich, dass \Os_{d} mit dieser Topologie ein (DFS)-Raum wird. R\"aume dieser Klasse erscheinen als besonders geeigneter Rahmen f\"ur die Verwendung von Konzepten unendlichdimensionaler Analysis, da hier verschiedene Zug\"ange \"ubereinstimmen und glatte Funktionen stetig sind, was im Allgemeinen falsch ist. In Kapitel drei wird ein kurzer \"Uberblick \"uber zwei Konzepte holomorpher Funktionen zwischen lokalkonvexen R\"aumen geschaffen. In Kapitel vier wird dann speziell auf \Os_{d} eingegangen, und ein Resultat von Boland und Dineen, wonach jede holomorphe Funktion \Os_{d}^{p} \to \C in eine Taylorreihe bestehend aus Monomen entwickelt werden kann, auf holomorphe Funktionen \Os_{d}^{p} \to \Os_{d} verallgemeinert. Im letzten Kapitel wird dann eine Klasse holomorpher Funktionen, deren Koeffizienten eine \"ahnliche Struktur wie jene von Substitutionsabbildungen besitzen, betrachtet. Zun\"achst werden Abbildungen dieser Klasse, welche den konstanten Term ignorieren -- die wir als textile Abbildungen bezeichnen -- untersucht. Diese zeigen ein \"ahnliches Verhalten wie lineare Abbildungen zwischen normierten R\"aumen: sie sind stetig genau dann wenn sie auf einer "Kugel" beschr\"ankt sind und die selbe Bedingung ist hinreichend daf\"ur, dass Abbildungen dieser Klasse ganze Funktionen sind. Ausgestattet mit der kompakt-offenen Topologie wird der Raum dieser Abbildungen zu einem (DFS)-Raum. Diese Resultate werden dann auf allgemeinere Klassen ausgeweitet. Im letzten Teil dieses Kapitels betrachten wir die Differentialgleichung , wobei eine verallgemeinerte textile Abbildung ist. Es wird gezeigt, dass diese bei analytischer Anfangsbedingung analytisch l\"osbar ist. Dieses Resultat kann so interpretiert werden, dass die Differentialgleichung analytisch l\"osbar bleibt, wenn die Koeffizienten der rechten Seite (aufgefasst als holomorphe Abbildung \Os_{d}^{p} \to \Os_{d}^{p}) stetig perturbiert werden.This thesis deals with holomorphic functions \Os_{d}^{p} \to \Os_{d}, where \Os_{d} denotes the ring of convergent power series in variables. In the first two chapters the necessary concepts from functional analysis and topology are developed.
The representation of \Os_{d} as union of weighted Banach spaces yields a natural inductive topology, where is the Banach space of power series for which is finite. It turns out that \Os_{d} is a (DFS)-space, which seems to be the best setting for the usage of concepts of infinite-dimensional calculus, as different approaches coincide and smooth functions are always continuous, which is in general false. In chapter three we give an overview of two concepts of holomorphicity. Chapter four then specifically deals with \Os_{d} and the holomorphic functions on it. We extend the result by Dineen and Boland, that holomorphic functions \Os_{d} \to \C can be expanded into monomial series, to the vector-valued case \Os_{d} \to \Os_{d} and establish some results on the space (\mathcal{H}(\Os_{d}^{p}, \Os_{d}),\tauco). The last chapter treats a special class of holomorphic functions \Os_{d}^{p} \to \Os_{d}, whose Taylor coefficients have a similar structure as those of substitution maps\\ . We start by studying such maps that ignore the constant term -- which we call textile maps -- which behave similar to linear maps in normed spaces: they are continuous if and only if they preserve the boundedness of a "ball". The same condition also implies that maps of this class are entire functions. It is then shown that the space of these maps equipped with the compact-open topology is a (DFS)-space and the results established before are then generalized to broader classes. Finally we turn our attention to the differential equation , where the right side is a generalized textile map, and show that it is analytically solvable for analytical initial conditions. A consequence of this result is that (where is a convergent power series) remains analytically solvable if the coefficients of the right side (considered as a holomorphic function \Os_{d}^{p} \to \Os_{d}^{p}) are continuously perturbated.
%Finally we turn our attention to the differential equation , where the right side is a generalized textile map, and show that it is analytically solvable for analytical initial conditions.
%This result can be interpreted in the way that remains analytically solvable if the coefficients of the right side (considered as a holomorphic function \Os_{d}^{p} \to \Os_{d}^{p}) are continuously perturbated
On varieties in power series spaces
No full textIn dieser Arbeit werden verschiedene Aspekte der Geometrie von so genannten arquilen Varietäten, welche die Lösungsmengen Y(f) von impliziten Potenzreihengleichungen f(x,y(x)) = 0 sind, untersucht. Diese Gleichungen enstsprechen einem unendlichen System an polynomialen Gleichungen F_{i}(y_{alpha}) = 0 in den Koeffizienten y_{alpha} von y(x). Der übliche Zugang, der beispielsweise in der Theorie der arc spaces gewählt wird, ist, die Lösungsmenge Y(f) als die Menge der abgeschloßenen Punkte des durch die Koeffizientenpolynome definierten unendlich-dimensionalen Schemas zu betrachten. Der Nachteil dieses Ansatzes ist jedoch, dass geometrische Konzepte wie das der Regularität im Unendlichdimensionalen nicht mehr zu Verfügung stehen. Stattdessen werden in dieser Arbeit Potenzreihen y(x) mit (nicht-abgeschloßenen) Punkten P_{y} des Spektrums von C[|x,y|] identifiziert, wodurch es möglich ist, Begriffe von Regularität von arquilen Varietäten zu definieren und mithilfe geeigneter Jakobi-Kriterien zu charakterisieren. Geometrisch gesehen entspricht die Regularität (im Falle einer einzelnen unabhängigen Variable) der Glattheit der Lösungsmenge in dem Sinne, dass eine Umgebung der Varietät zu einer Umgebung in einem freien Potenzreihenmoduls isomorph ist.The main objective of this thesis is to understand certain aspects of the geometry of the set of solutions Y(f) to an implicit power series equation f(x,y(x)) = 0. This equation corresponds to an infinite system of polynomial equations F_{i}(y_{\alpha}) = 0 in the coefficients y_{\alpha} of y.
The usual approach to understand these systems is to consider Y(f) as the closed points of the infinite-dimensional scheme defined by the coefficient polynomials, which has the disadvantage that finite-dimensional geometrical concepts such as regularity are not available. Instead, in this work we identify power series y(x) with (non-closed) points y(x) of the spectrum of C[|x,y|], which makes it possible to define notions of regularity and characterize these notions accordingly with adopted versions of the Jacobian criterium. Geometrically, the regularity of an arquile variety (in the case of a single independent variable) corresponds to the smoothness of the variety in the sense (of differential geometry) that locally the arquile variety is isomorphic to a neighborhood of a free power series module
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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