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A Genealogy of Correspondence Analysis
No full textOver the past half a century correspondence analysis has grown from a little known statistical technique designed to graphically depict the association structure of categorical variables that form a contingency table to a very popular tool used in a wide variety of disciplines. Despite this growth, correspondence analysis remains relatively unknown in the Australasian statistical community
Confidence regions and Approximate P-values for classical and non-symmetrical correspondence analysis.
No full textVariants of Simple Correspondence Analysis
Full text linkThis paper presents a description of the R package CAvariants. It performs six variants of correspondence
analysis on a two-way contingency table. The main function that shares the same name
as the package - CAvariants - allows the user to choose (via a series of input parameters) from six
different correspondence analysis procedures. These include the classical approach to (symmetrical)
correspondence analysis, singly ordered correspondence analysis, doubly ordered correspondence
analysis, non symmetrical correspondence analysis, singly ordered non symmetrical correspondence
analysis and doubly ordered non symmetrical correspondence analysis. The code provides the flexibility
for constructing either a classical correspondence plot or a biplot graphical display. It also allows
the user to consider other important features that allow for one to assess the reliability of the graphical
representations, such as the inclusion of algebraically derived elliptical confidence regions. This paper
provides R functions that elaborates more fully on the code presented in Beh and Lombardo (2014)
Application of correspondence analysis to graphically investigate associations between foods and eating locations
Full text linkThis paper presents the application of correspondence analysis (CA) for
investigating associations using confidence regions (CRs) with a focus on
facilitating mining the data and hypothesis generation. We study the relationship
between locations and “less-healthy” food consumption by UK teenagers. CA
allows for a quick visual inspection of the various association structures that exist
between the categories of cross-classified variables in large datasets derived with
varying study designs. The hypotheses generated by the visual display can then be
independently tested using suitable regression models. CA makes use of readily
available software tools and of robust statistical tests amenable to interpretation
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
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
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