2,965 research outputs found

    Bayesian model comparison and model averaging for small-area estimation

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    This paper considers small-area estimation with lung cancer mortality data, and discusses the choice of upper-level model for the variation over areas. Inference about the random effects for the areas may depend strongly on the choice of this model, but this choice is not a straightforward matter. We give a general methodology for both evaluating the data evidence for different models and averaging over plausible models to give robust area effect distributions. We reanalyze the data of Tsutakawa [Biometrics 41 (1985) 69--79] on lung cancer mortality rates in Missouri cities, and show the differences in conclusions about the city rates from this methodology.Comment: Published in at http://dx.doi.org/10.1214/08-AOAS205 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

    Content wizard: Concept-based recommender system for instructors of programming courses

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    Authoring an adaptive educational system is a complex process that involves allocating a large range of educational content within a fixed sequence of units. In this paper, we describe Content Wizard, a concept-based recommender system for recommending learning materials that meet the instructor's pedagogical goals during the creation of an online programming course. Here, the instructors are asked to provide a set of code examples that jointly re.ect the learning goals that are associated with each course unit. The Wizard is built on top of our course-authoring tool, and it helps to decrease the time instructors spend on the task and to maintain the coherence of the sequential structure of the course. It also provides instructors with additional information to identify content that might be not appropriate for the unit they are creating. We conducted an o.- line study with data collected from an introductory Java course previously taught at the University of Pittsburgh in order to evaluate both the practicality and effectiveness of the system. We found that the proposed recommendation's performance is relatively close to the teacher's expectation in creating a computer-based adaptive course

    Smart homes, control and energy management:How do smart home technologies influence control over energy use and domestic life?

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    By introducing new ways of automatically and remotely controlling domestic environments smart technologies have the potential to significantly improve domestic energy management. It is argued that they will simplify users’ lives by allowing them to delegate aspects of decision-making and control - relating to energy management, security, leisure and entertainment etc. - to automated smart home systems. Whilst such technologically-optimistic visions are seductive to many, less research attention has so far been paid to how users interact with and make use of the advanced control functionality that smart homes provide within already complex everyday lives. What literature there is on domestic technology use and control, shows that control is a complex and contested concept. Far from merely controlling appliances, householders are also concerned about a wide range of broader understandings of control relating, for example, to control over security, independence, hectic schedules and even over other household members such as through parenting or care relationships. This paper draws on new quantitative and qualitative data from 4 homes involved in a smart home field trial that have been equipped with smart home systems that provide advanced control functionality over appliances and space heating. Quantitative data examines how householders have used the systems both to try and improve their energy efficiency but also for purposes such as enhanced security or scheduling appliances to align with lifestyles. Qualitative data (from in-depth interviews) explores how smart technologies have impacted upon, and were impacted by, broader understandings of control within the home. The paper concludes by proposing an analytical framework for future research on control in the smart home

    Caffeine and near point plus acceptance

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    The relationship between caffeine consumption and near plus acceptance is investigated. Forty subjects monitored their caffeine consumption for three weeks. The subjects were then categorized according to their average daily caffeine consumption as low, moderate, or high consumers. Plus lens acceptance was determined by improved performance scores on the Kirschner Visual Performance Test (KVPT) . Each subject took the KVPT six times: twice through their habitual near lens, twice through +0.50 D in addition ~o their habitual near l ens , and twice through +0.75 D in addition to their habitual near lens. Statistical analysis showed no significant relationship between near plus lens acceptance and caffeine consumption

    An analysis of differential item functioning by gender in the Learning Disability Screening Questionnaire (LDSQ)

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    The Learning Disability Screening Questionnaire (LDSQ; McKenzie & Paxton, 2006) was developed as a brief screen for intellectual disability. Although several previous studies have evaluated the LDSQ with respect to its utility as a clinical and research tool, no studies have considered the fairness of the test across males and females. In the current study we, therefore, used a multi-group item response theory approach to assess differential item functioning across gender in a sample of 211 males and 132 females assessed in clinical and forensic settings. Although the test did not show evidence of differential item functioning by gender, it was necessary to exclude one item due to estimation problems and to combine two very highly related items (concerning reading and writing ability) into a single literacy item Thus, in addition to being generally supportive of the utility of the LDSQ, our results also highlight possible areas of weakness in the tool and suggest possible amendments that could be made to test content to improve the test in future revisions

    Understanding tensions and identifying clinician agreement on improvements to early-stage chronic kidney disease monitoring in primary care : a qualitative study

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    Funding This article presents independent research funded by the National Institute for Health Research School for Primary Care Research (NIHR SPCR) (reference:120). JE was also supported by the NIHR Programme Grants for Applied Research programme (Reference: RP-PG-1210-12012). DSL and LL are supported by the NIHR Oxford Biomedical Research CentrePeer reviewedPublisher PD

    Authoring knowledge based tutors: ‘tools for content, instructional strategy, student model, and interface design

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    Abstract While intelligent tutoring systems (ITSs), also called knowledge based tutors, are becoming more common and proving to be increasingly effective, each one must still be built from scratch at a significant cost. We have developed domain independent tools for authoring all aspects of a knowledge based tutor: the domain model, the teaching strategies, the student model, and the learning environment. In this paper we describe these tools, discuss a number of design issues and design tradeoffs that are involved in building ITS authoring tools, and discuss knowledge acquisition and representation issues encountered in our work. We also describe how we plan to use these tools (collectively called Eon), including "ontology objects," as a meta-authoring tool for designing special purpose authoring tools tailored for specific domain types
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