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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
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
The n! Conjecture and the Isospectral Hilbert Scheme of Points
No full textThe goal of this thesis is to introduce and prove the conjecture, this work is mainly based on the work of Mark Haiman from 1992 to 2001.\\
The conjecture was for the first time approached to try to prove another conjecture, the positivity conjecture about the Kostka coefficients which states that they belongs to the polynomial ring .\\
It was known that the modules involved in the conjecture are quotients of the ring of coinvariants for the action of on , denoted as , and also that was isomorphic to the space of diagonal harmonics. Unfortunately, despite the computations suggesting that the dimension of should be , proving it resulted very hard.\\
In the spring of 1992 Procesi and Haiman discussed the topic: Procesi suggested that the Hilbert scheme and what we now call the isospectral Hilbert scheme should be relevant to the determination of the dimension and character of . Specifically, he observed that there is a natural map from to the ring of global functions on the scheme-theoretic fiber in over the origin in the symmetric power , and with some luck this map could be an isomorphism! But let us make a step back and introducing the conjecture properly.\\
Let be a tuple of natural numbers such that .\\
We define the Young Diagram associated to as the subset of such that
\begin{equation*}
d(\mu)=\{(p,q)\,|\,p<\mu_{q+1}\}.
\end{equation*}
The conjecture states that if we take the alternating polynomial defined as for and we compute the space of all derivatives
\begin{equation*}
D_{\mu}=\mathbb{C}[\partial \bold x, \partial \bold y]\Delta_{\mu},
\end{equation*}
the dimension of is always .\\
Now it is important to see that there are three main topics to treat:
\begin{enumerate}
\item\label{intro_n!_conj} The conjecture regarding the space
\item \label{intro_pos_conj} The positivity conjecture regarding the Kostka coefficients
\item\label{intro_X_n} The isospectral Hilbert scheme of points and its natural map
to the Hilbert scheme.
\end{enumerate}
In this introduction my goal is to make clear the connections between the points \ref{intro_n!_conj} and \ref{intro_X_n} as they are the main focus of this thesis. In Chapter the curious reader will also find a brief explaination of the connection between points \ref{intro_pos_conj} and \ref{intro_n!_conj}.\\
Let us begin with some mathematics.\\
The first thing that we can notice is that, if we take the ideal generated by for it is a monomial ideal, we will denote it by .\\
There is a very nice property of monomial ideals: they are the fixed points of the action of on the Hilbert scheme! Let's see why.\\
It's clear that acts on sending to , very similarly acts on by
\begin{equation*}
(t_{1},t_{2})I=(t_{1},t_{2})(f_{1}(x,y),\dots, f_{m}(x,y))\to (f_{1}(t_{1}x,t_{2}y),\dots,f_{m}(t_{1}x,t_{2}y)),
\end{equation*}
so if is monomial we can just factor the out without modifying anything.\\
The other important class of points of are the generic points denoted by , the ideals which vanishes on a specified finite set of distinct points of cardinality . In this very beautiful case is radical and is reduced and isomorphic to .
Intuitively we can think to as a set of points with multiplicity one and to as the origin with multiplicity .\\
Notice that in the order of the points does not matter whether in it does, so it is natural to consider the map
\begin{equation*}
\sigma:H_{n}\to \mathbb{C}^{n}/S_{n}
\end{equation*}
sending to the unordered n-tuple of points. Notice that each appears in the -tuple a number of time equal to its multiplicity.\\
Now is called the \textit{Hilbert Chow Morphism} and it is a morphism of algebraic varieties and note that for all distinct in there is only one ideal such that , thus, giving the fact that the generic locus is dense in the map is \textit{birational}.\\
Later we will see that can also be described as a certain blowup of , so we can look at the Hilbert scheme of points as a resolution of the singularities of .\\
To recap let us look at the following diagram:
\begin{center}
\begin{tikzcd}
&\mathbb{C}^{2n}\arrow{d}\\
H_{n}\arrow{r}{\theta}& S_{n}\mathbb{C}^2
\end{tikzcd}
\end{center}
and notice that if we take a point , we move it in and then we take the fiber in these fibers have lenght , in fact they are the sets of all possible orders of distinct points.\\
Unfortunately this argument does not hold for the monomial ideals thus we have to find another way to prove the conjecture.\\
An important property of finite flat morphism of schemes is that each fiber has the same lenght.\\
Now suppose that we can find a scheme lying above such that the map
\begin{equation*}
\rho:Y\to H_{n}
\end{equation*}
is flat and the fibers of a generic ideal have lenght , then we can use that property and conclude the proof!
Sadly the trivial choice of completing the above diagram with the fiber product does not work, the map is not flat.\\
Haiman's is to complete the diagram above with the reduced fiber product of and over , we will call this space the \textit{isospectral Hilbert scheme} and denote it with .
\begin{center}
\begin{tikzcd}
X_{n}\arrow{d}{\rho}\arrow{r}&\mathbb{C}^{2n}\arrow{d}\\
H_{n}\arrow{r}{\theta}& S_{n}\mathbb{C}^2
\end{tikzcd}
\end{center}
Now because is nonsingular and the projection is finite, being Cohen-Macaulay is equivalent to being flat.\\
In particular the procedure is the following: we define the sheaf over the Hilbert scheme of points as the push-forward of where is the universal family of . Then we prove that we can see as \spec(B^{\otimes n}/\mathcal{J}) for a certain sheaf of ideals and we prove that the ring
is Cohen-Macaulay and Gorenstein.\\
There exists a very strong result (see \cite{emsalem1978geometrie}) proving that, up to isomorphism, a local Artinian -algebra is Gorenstein if and only if it is of the form where
in other words is the vector space generated bya polynomial its partial derivarives of all orders.\\
So, proving that our ring is Gorenstein it is actually equivalent to proving that it is of the form . Subsequently, with some computations, we manage to identify this ideal , and with it, the dimension and the structure of our ring.\\
The process of proving Gorenstein is very insidious, approximately it goes like that:
\begin{itemize}
\item We prove that is normal with a very ingenious argument using an algebraic structure called \textit{Polygraphs}.
\item We prove that the Gorenstein property is equivalent to the conjecture, thus even the opposite implication works.
\item We prove the conjecture by hand for , then we start with an induction argument.
\item We use the equivalence: Cohen-Macaulay if and only if flat for normal varieties to suppose
flat.
\item We use this ipothesis to prove that if is Gorenstein then is Gorenstein too.
\item is Gorenstein because the conjecture holds, thus is Gorenstein and the conjecture holds.
\end{itemize}
This thesis is organized into three chapters: the first one introduces the conjectures formally, gives an example of the conjecture for small and delves into some element of representation theory of finite groups.
In the second chapter we dive into the algebraic geometry of the Hilbert scheme, the isospectral Hilbert scheme and we give a proof of the conjecture. During this proof we claim that the ideal
where is the space of alternating polynomials is a free -module, the proof of this fact will take the entire third chapter.
Finally in the third chapter we introduce \textit{polygraphs}, a particular union of linear subspaces in where \\
The motivation behind the name is that their constituent subspaces are the graphs of linear maps from to .\\
The purpose of this section is to actually prove that the ring
of the polygraph is a free -module. Finally we find a map between this ring and taht concludes the argument.\
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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