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Statistical contributions to psychological modelling
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146832.pdf (Publisher’s version ) (Open Access)116 p
Balancing simple models and complex reality
No full textThe first part of the dissertation dealt with conditional independence and conditional dependence between response time and accuracy. Conditional independence - as formulated by most joint models for response times and accuracy applied in the context of educational measurement - means that given the latent variables of speed and ability the response accuracy and the response time of the same item are independent. Conditional dependence, on the other hand, means that the relationship between the response time and accuracy cannot be fully explained by the higher-level relationship between the persons’ latent variables, or between the item characteristics related to time and accuracy. The first two chapters of Part I developed tools that help to answer the question of whether relatively simple response time and accuracy models assuming conditional independence adequately represent the complex relationships between time and accuracy in the data. The last chapter of Part I proposed to give up some of the model simplicity in order to explain the complex structure in the data and gain more insight into the substantively interesting response processes. The second part of the dissertation dealt with three different research questions, all answered using a Bayesian approach. In Chapter 5 the multi-scale Rasch model consisting of Rasch homogenous scales was proposed and a tool for unmixing Rasch scales was provided. The choice of the model was directly motivated by the idea of optimally balancing the simplicity of the model with the complexity of the data: It keeps an important measurement property of the simple Rasch model - sufficiency of the sumscore within each scale for the corresponding person parameter - but relaxes other assumptions of the Rasch model (equality of discriminations of all items in the test and unidimensionality) which often do not match the complexity of the educational data
Conditional statistical inference with multistage testing designs
No full textIn this paper it is demonstrated how statistical inference from multistage test designs can be made based on the conditional likelihood. Special attention is given to parameter estimation, as well as the evaluation of model fit. Two reasons are provided why the fit of simple measurement models is expected to be better in adaptive designs, compared to linear designs: more parameters are available for the same number of observations; and undesirable response behavior, like slipping and guessing, might be avoided owing to a better match between item difficulty and examinee proficiency. The results are illustrated with simulated data, as well as with real data
Testing the race model inequality: A nonparametric approach
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63655.pdf (Publisher’s version ) (Open Access)This paper introduces a nonparametric procedure for testing the race model explanation of the redundant signals effect. The null hypothesis is the race model inequality derived from the race model by Miller (Cognitive Psychol. 14 (1982) 247). The construction of a nonparametric test is made possible by a small change in the usual experimental procedure. This change involves that whenever only a single stimulus is presented, its modality is determined independently from the previous trials. It is shown that the test procedure is consistent against every violation of the null hypothesis. The test procedure is developed for data from a single participant, but it can easily be extended to the testing of the null hypothesis across participants, and this is also shown in the paper. (C) 2003 Elsevier Inc. All rights reserved
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
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