5,220 research outputs found
Scoring and estimating score precision using multidimensional IRT
Full text linkThe ultimate goal of measurement is to produce a score by which individuals can be assessed and differentiated. Item response theory (IRT) modeling views responses to test items as indicators of a respondent’s standing on some underlying psychological attributes (van der Linden & Hambleton, 1997) – we often call them latent traits – and devises special algorithms for estimating this standing. This chapter gives an overview of methods for estimating person attribute scores using one-dimensional and multi-dimensional IRT models, focusing on those that are particularly useful with patient-reported outcome (PRO) measures.
To be useful in applications, a test score has to approximate the latent trait well, and importantly, the precision level must be known in order to produce information for decision-making purposes. Unlike classical test theory (CTT), which assumes the precision with which a test measures the same for all trait levels, IRT methods assess the precision with which a test measures at different trait levels. In the context of patient-reported outcomes measurement, this enables assessment of the measurement precision for an individual patient. Knowing error bands around the patient’s score is important for informing clinical judgments, such as deciding upon significance of any change, for instance in response to treatment etc. (Reise & Haviland, 2005). At the same time, summary indices are often needed to summarize the overall precision of measurement in a research sample, population group, or in the population as a whole. Much of this chapter is devoted to methods for estimating measurement precision, including the score-dependent standard error of measurement and appropriate sample-level or population-level marginal reliability coefficients.
Patient-reported outcome measures often capture several related constructs, the feature that may make the use of multi-dimensional IRT models appropriate and beneficial (Gibbons, Immekus & Bock, 2007). Several such models are described, including a model with multiple correlated constructs, a model where multiple constructs are underlain by a general common factor (second-order model), and a model where each item is influenced by one general and one group factor (bifactor model). To make the use of these models more easily accessible for applied researchers, we provide specialized formulae for computing test information, standard errors and reliability. We show how to translate a multitude of numbers and graphs conditioned on several dimensions into easy-to-use indices that can be understood by applied researchers and test users alike. All described methods and techniques are illustrated with a single data analysis example involving a popular PRO measure, the 28-item version of the General Health Questionnaire (GHQ28; Goldberg & Williams, 1988), completed in mid-life by a large community sample as a part of a major UK cohort study
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
Money piece by Timothy P. Agnew, chief executive officer of the Finance Author
No full textMoney piece by Timothy P. Agnew, chief executive officer of the Finance Authority of Maine, about the increased availability of credit for Maine\u27s small businesses
Timothy Meyer serves as a contributing author for UN report
No full textAssistant Professor Timothy Meyer served as a contributing author for the United Nations Industrial Development Organization\u27s report titled Networks for Prosperity: Connecting Development Knowledge Beyond 2015. The document, which was released during November, analyzes the nexus between the global connectedness of a country and its economic success, sustainability and government effectiveness. Meyer was one of only approximately 20 academic and practical experts from around the world selected to serve as a contributor after a global call for proposals.
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Selected Contributions of Sister Mary Berenice Beck, O.S.F. to Nursing in the United States, 1923-1956
No full textby Sister M. Timothy Costello.Typescript.Thesis (M.S.N.)--Catholic University of America.Bibliography: leaves 44-47.Also available in microfilm
The Baptismal Liturgy of Theodore of Mopsuestia
No full textTimothy A. Curtin.Typescript.Thesis (S.T.D.)--Catholic University of America, 1971.Bibliography: leaves 368-393
Five minutes with Timothy Gowers: “academics can publish journals of the highest quality without a commercial entity”
Full text linkFields Medal-winning Cambridge mathematician Sir Timothy Gowers and a team of colleagues have recently launched a new editor-owned Open Access (OA) journal for mathematics. Discrete Analysis is an arXiv overlay journal, which means articles are submitted and hosted via the preprint server arXiv first. The journal coordinates peer-review and publishes via Scholastica with no cost to reader or author. Gowers reflects here on his vision for the future of editor-owned journals
First person – Timothy Cummins
No full textABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Timothy Cummins is the first author on ‘PAWS1 controls cytoskeletal dynamics and cell migration through association with the SH3 adaptor CD2AP’, published in Journal of Cell Science. Timothy is an Assistant Professor of Medicine at the University of Louisville School of Medicine Clinical Proteomics Center, which focuses on identifying biomarkers of kidney diseases by using quantitative mass spectroscopy.</jats:p
ASO Author Reflections: Re-resection of Positive Bile Duct Margin for Hilar Cholangiocarcinoma
No full textAuthor Reflections: Re-resection of Positive Bile Duct Margin for Hilar Cholangiocarcinom
Practical Equality: Discussion with Author Robert L. Tsai
No full textProfessor Timothy Zick discusses a new book titled Practical Equality: Forging Justice in a Divided Nation, with its author, Professor Robert L. Tsai of American University Washington College of Law. Timothy Zick is the John Marshall Professor of Government and Citizenship at William & Mary Law School. His scholarship has explored a wide variety of constitutional issues, with a special focus on the First Amendment. Robert L. Tsai is Professor of Law at American University and a prize-winning essayist in constitutional law and history. Recorded before a live audience at William & Mary Law School on March 14, 2019. The event was sponsored by the American Constitution Society. Professor Tsai was also a panelist during the annual Bill of Rights Journal Symposium on March 15 & 16, 2019
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