1,720,952 research outputs found
An Item Response Theory Approach to the Maintenance of Standards in Public Examinations in England
Get PDFAbstract
Every year outcomes from public examinations in the UK rise: politicians congratulate pupils on their hard earned achievement; the media questions whether this achievement is real; those responsible for administrating the examinations defend their standards; various subject councils and employers decry the failings of candidates with high grades; admissions officers from the elite universities report their struggle with the decrease in discrimination in grades achieved; and academics debate what it means to compare standards from one year to the next. The debate cannot be easily resolved because examination results are put to many purposes some of which are more suited to certain definitions of comparability than others. In procedural terms, however, it should be relatively straightforward to evaluate the strength of the evidence that is put forward on the comparability of standards against various definitions.
Broadly, solely in terms of discrimination, the statistical evidence in the maintenance of standards over time and between qualifications can be evaluated by reference to measures such as model fit, significance and effect size. An evaluation of the literature suggests that predictive statistical models, where employed in the maintenance of standards to meet definitions of cohort referencing, tend to be robust. Beyond discrimination, measures of performance standards are required to support inferences drawn from grades on what candidates can actually do. These are, and have been for many years, underpinned by processes reliant on human judgement. An evaluation of the literature suggests that judgement provides very weak evidence and is subject to unknown bias. The combination of statistical and judgemental evidence is poorly specified, has no theoretical basis and is therefore impossible to evaluate. If anything more than pure cohort referencing is required from public examinations in the UK there is clearly a need to explore models with a sound theoretical basis whose evidence can be evaluated in terms of model fit, significance and effect size.
The task of maintaining a performance standard can essentially be reduced under test theory to making comparisons between persons that are independent of the items on the basis of which these comparisons are made. Test theory however has been sparingly applied to comparability issues in UK public examinations. This study considers which test theory model would be most suited to the examinations in use in the UK, examines issues of model fit under frequentist and Bayesian frameworks, compares the results from different test equating methods and the practical issues of implementing a test equating design under the given constraints of the UK examination system.
To begin with the Rasch model and the One Parameter Logistic Model were fitted to operational data gathered from examinations in a range of subject domains where marking reliability would not be considered as a potential confound. In this framework the Rasch model requirement of a single discrimination parameter across items appeared overly restrictive. Further, potential issues with model fit were highlighted related to dimensionality, guessing and weak local independence. More complex models were therefore pursued under a Bayesian framework. The Posterior Predictive Model Checking Procedures and Deviance Information Criterion confirmed that a model which allowed discrimination to vary across items, such as the two-parameter Item Response Theory model, would produce better model predictions. Use of the Multi-Class Mixture Rasch Model suggested that multidimensionality due to a confounding speededness factor could result in misleading inferences being drawn from unidimensional models. The Testlet Response Theory model showed enhanced predictions where weak local independence was correctly specified; however it proved difficult to specify where this weak local independence was expected. When tests from one of the examinations particularly affected by speededness were equated OPLM proved more robust to the confounding speededness factor than the Rasch model.
A Post-equating Non-Equivalent Groups Design was then set up as an experiment using a set of relatively simple Science examinations and candidates at a later stage in their programme of study than those who would take the live examinations in order to understand some of the practical issues involved in equating designs. The study found that item parameters were not stable across samples due to context effects, school effects and maturity effects. These results were partly due to the scale of study, which, though small, still produced reasonably sensible outcomes. It is suggested that more care paid to the context of linking items, their underlying construct, and the sampling of schools would yield more robust results. Finally, a qualitative exploration of views related to test equating designs suggested that teachers, pupils and examiners would not reject the possibility of embedding equating items into live tests.
For examinations where marking reliability is not considered an issue the results reported here suggest that the use of test theory could provide a unified theoretical framework for the maintenance of standards in UK public examinations which would allow the strength of the evidence presented to be evaluated. This would represent a substantial improvement over the current situation in which no comprehensive or coherent evaluation can be made. The time and investment required, however, to introduce such a framework is also substantial. A suitable technical infrastructure is required as well as psychometric expertise. The alternative is to revert to an examinations system that is essentially cohort referenced and focuses on discrimination between candidates in any one year rather than attempting to quality assure, as it cannot do, performance standards from one year to the next
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
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
- …
