3,016 research outputs found

    Systematic misregistration and the statistical analysis of surface data.

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    Spatial normalisation is a key element of statistical parametric mapping and related techniques for analysing cohort statistics on voxel arrays and surfaces. The normalisation process involves aligning each individual specimen to a template using some sort of registration algorithm. Any misregistration will result in data being mapped onto the template at the wrong location. At best, this will introduce spatial imprecision into the subsequent statistical analysis. At worst, when the misregistration varies systematically with a covariate of interest, it may lead to false statistical inference. Since misregistration generally depends on the specimen's shape, we investigate here the effect of allowing for shape as a confound in the statistical analysis, with shape represented by the dominant modes of variation observed in the cohort. In a series of experiments on synthetic surface data, we demonstrate how allowing for shape can reveal true effects that were previously masked by systematic misregistration, and also guard against misinterpreting systematic misregistration as a true effect. We introduce some heuristics for disentangling misregistration effects from true effects, and demonstrate the approach's practical utility in a case study of the cortical bone distribution in 268 human femurs.This is the author’s version of a work that was accepted for publication in Medical Image Analysis. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Medical Image Analysis, [Volume 18, Issue 2, February 2014] DOI http://dx.doi.org/10.1016/j.media.2013.12.007

    That’s more like they know me as a person": one primary pre-service teacher’s stories of her personal and ‘professional’ digital practices

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    In contributing to debates about how student-teachers might draw from personal experience in addressing digital literacy in the classroom, this paper explores the stories that one primary student-teacher told of her digital practices during a larger study of the role of digital literacy in student-teachers' lives. The paper investigates the 'recognition work' this student-teacher did as she aligned herself with different discourses and notes how themes of 'control' and 'professionalism' seemed to pattern her stories of informal and formal practices both within and beyond her professional education. The paper calls for further research into how student-teachers perceive the relevance of their personal experience to their professional role and argues for encouraging pre-service and practising teachers to tell stories of their digital practices and reflect upon the discourses which frame them

    The political constitution at 40

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    The constitution ‘is no more and no less than what happens’. So wrote Professor John Griffith in the 1978 Chorley Lecture, which was later republished in the Modern Law Review in 1979. It was not the first time that Griffith dangled this tantalizing aphorism before his readers, but it was this lecture that saw it melt into the vocabulary of public law. It might seem trite to spotlight this aphorism from what is a rich and intricate lecture full of important insights as well as memorable phrases. However, as we see it, and writing at the end of March 2019, constitutional practice over the last three years —or, for that matter, the last three months, the last three weeks, or even the last three days—underscores the continuing relevance of Griffith’s insights into the complex and contingent nature of the relationship between law, politics and the constitution
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