1,721,047 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Geometric Models of Concurrent Computations
No full textSince the 90s, geometric models have been introduced for concurrent programs. In those, a point corresponds to a state, a path to an execution and a deformation of a path to an equivalence between executions. They are useful to analyze programs because they provide a convenient representation of their state space, on which one can use some of the well-developed tools and invariants from geometry (curvature, homology, etc.). Conversely, the study of the spaces arising as models brings new problems of purely geometric nature: most importantly, they are naturally equipped with a direction (of time), which requires adapting most usual notions. In this habilitation thesis, we present such models that we have developed and studied, as well as general techniques to do so and the results they have allowed us to obtain. Those have been applied to various notion of "concurrent programs": programs in an imperative language extended with a parallel construction and resources, but also distributed protocols, version control systems, or rewriting systems. The “geometric models” we have studied for those are also of various nature: precubical sets, directed topological spaces, generalized metric spaces, or polygraphs
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Presentation of a Game Semantics for First-Order Propositional Logic
Full text linkGame semantics aim at describing the interactive behaviour of proofs by interpreting formulas as games on which proofs induce strategies. In this article, we introduce a game semantics for a fragment of first order propositional logic. One of the main difficulties that has to be faced when constructing such semantics is to make them precise by characterizing definable strategies - that is strategies which actually behave like a proof. This characterization is usually done by restricting to the model to strategies satisfying subtle combinatory conditions such as innocence, whose preservation under composition is often difficult to show. Here, we present an original methodology to achieve this task which requires to combine tools from game semantics, rewriting theory and categorical algebra. We introduce a diagrammatic presentation of definable strategies by the means of generators and relations: those strategies can be generated from a finite set of ``atomic'' strategies and that the equality between strategies generated in such a way admits a finite axiomatization. These generators satisfy laws which are a variation of bialgebras laws, thus bridging algebra and denotational semantics in a clean and unexpected way
Coherence in cartesian theories using rewriting
Full text linkThe celebrated Squier theorem allows to prove coherence properties of
algebraic structures, such as MacLane's coherence theorem for monoidal
categories, based on rewriting techniques. We are interested here in extending
the theory and associated tools simultaneously in two directions. Firstly, we
want to take in account situations where coherence is partial, in the sense
that it only applies for a subset of structural morphisms (for instance, in the
case of the coherence theorem for symmetric monoidal categories, we do not want
to strictify the symmetry). Secondly, we are interested in structures where
variables can be duplicated or erased. We develop theorems and rewriting
techniques in order to achieve this, first in the setting of abstract rewriting
systems, and then extend them to term rewriting systems, suitably generalized
in order to take coherence in account. As an illustration of our results, we
explain how to recover the coherence theorems for monoidal and symmetric
monoidal categories
PROGRAM = PROOF
No full textInternational audienceThis course provides a first introduction to the Curry-Howard correspondence between programs and proofs, from a theoretical programmer's perspective: we want to understand the theory behind logic and programming languages, but also to write concrete programs (in OCaml) and proofs (in Agda). After an introduction to functional programming languages, we present propositional logic, λ-calculus, the Curry-Howard correspondence, first-order logic, Agda, dependent types and homotopy type theory
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