3,044 research outputs found
Exploratory talk within collaborative small groups in mathematics
This report describes one aspect of a wider research study on exploratory talk within collaborative small groups in secondary mathematics lessons. It outlines students’ views of using collaborative activity to learn mathematics. The fuller research study explores the extent to which exploratory talk occurs in collaborative peer groups in secondary mathematics classrooms
Impact of outcome adjudication in kidney disease trials: observations from the Study of Heart and Renal Protection (SHARP)
Introduction: We aimed to assess opportunities for trial streamlining and the scientific impact of adjudication on kidney and cardiovascular outcomes in CKD.
Methods: We analysed the effects of adjudication of ~2100 maintenance kidney replacement therapy (KRT) and ~1300 major atherosclerotic events (MAEs) recorded in SHARP. We first compared outcome classification before versus after adjudication, and then re-ran randomised comparisons using pre-adjudicated follow-up data.
Results: For maintenance KRT, adjudication had little impact with only 1% of events being refuted (28/2115). Consequently, randomised comparisons using pre-adjudication reports found almost identical results (pre-adjudication: simvastatin/ezetimibe 1038 vs placebo 1077; risk ratio [RR] 0.95, 95%CI 0.88–1.04; post-adjudicated: 1057 vs 1084; RR=0.97, 95%CI 0.89–1.05). For MAEs, about one-quarter of patient reports were refuted (324/1275 [25%]), and reviewing 3538 other potential vascular events and death reports identified only 194 additional MAEs. Nevertheless, randomised analyses using SHARP’s pre-adjudicated data alone found similar results to analyses based on adjudicated outcomes (pre-adjudication: 573 vs 702; RR=0.80, 95%CI 0.72-0.89; adjudicated: 526 vs 619; RR=0.83, 95%CI 0.74–0.94), and also suggested refuted MAEs were likely to represent atherosclerotic disease (RR for refuted MAEs=0.80, 95%CI 0.65−1.00).
Conclusions: These analyses provide three key insights. First, they provide a rationale for nephrology trials not to adjudicate maintenance KRT. Secondly, when an event that mimics an atherosclerotic outcome is not expected to be influenced by the treatment under study (e.g. heart failure), the aim of adjudicating atherosclerotic outcomes should be to remove such events. Lastly, restrictive definitions for the remaining suspected atherosclerotic outcomes may reduce statistical power
Usability dimensions in collaborative GIS
Collaborative GIS requires careful consideration of the Human-Computer Interaction (HCI) and Usability aspects, given the variety of users that are expected to use these systems, and the need to ensure that users will find the system effective, efficient, and enjoyable. The chapter explains the link between collaborative GIS and usability engineering/HCI studies. The integration of usability considerations into collaborative GIS is demonstrated in two case studies of Web-based GIS implementation. In the first, the process of digitising an area on Web-based GIS is improved to enhance the user's experience, and to allow interaction over narrowband Internet connections. In the second, server-side rendering of 3D scenes allows users who are not equipped with powerful computers to request sophisticated visualisation without the need to download complex software. The chapter concludes by emphasising the need to understand the users' context and conditions within any collaborative GIS project. © 2006, Idea Group Inc
Assessment of (computer-supported) collaborative learning
Within the Computer-Supported Collaborative Learning (CS)CL research community there has been an extensive dialogue on theories and perspectives on learning from collaboration, approaches to scaffold (script) the collaborative process, and most recently research methodology. In contrast, the issue of assessment of collaborative learning has received much less attention. This article discusses how assessment of collaborative learning has been addressed, provides a perspective on what could be assessed, and highlights limitations of current approaches. Since assessment of collaborative learning is a demanding experience for teachers and students alike, they require adequate computer-supported and intelligent tools for monitoring and assessment. A roadmap for the role and application of intelligent tools for assessment of (CS)CL is presented
Designing electronic collaborative learning environments
Electronic collaborative learning environments for learning and working are in vogue. Designers design them according to their own constructivist interpretations of what collaborative learning is and what it should achieve. Educators employ them with different educational approaches and in diverse situations to achieve different ends. Students use them, sometimes very enthusiastically, but often in a perfunctory way. Finally, researchers study them and—as is usually the case when apples and oranges are compared—find no conclusive evidence as to whether or not they work, where they do or do not work, when they do or do not work and, most importantly, why, they do or do not work. This contribution presents an affordance framework for such collaborative learning environments; an interaction design procedure for designing, developing, and implementing them; and an educational affordance approach to the use of tasks in those environments. It also presents the results of three projects dealing with these three issues
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Online Profiles and Unique Author Identifiers
Presentation for the Cross Timbers Library Collaborative (CTLC) Scholarly Communications and Digital Curation (SCDC) Affinity Group 2013 Winter Meeting. This presentation discusses online profiles and unique author identifiers, their importance, features, and strategies for successfully using them
Study of Heart and Renal Protection (SHARP) : randomized trial to assess the effects of lowering low-density lipoprotein cholesterol among 9,438 patients with chronic kidney disease
BACKGROUND: Lowering low-density lipoprotein (LDL) cholesterol with statin therapy has been shown to reduce the incidence of atherosclerotic events in many types of patient, but it remains uncertain whether it is of net benefit among people with chronic kidney disease (CKD).METHODS: Patients with advanced CKD (blood creatinine ≥ 1.7 mg/dL [≥ 150 μmol/L] in men or ≥ 1.5 mg/dL [ ≥ 130 μmol/L] in women) with no known history of myocardial infarction or coronary revascularization were randomized in a ratio of 4:4:1 to ezetimibe 10 mg plus simvastatin 20 mg daily versus matching placebo versus simvastatin 20 mg daily (with the latter arm rerandomized at 1 year to ezetimibe 10 mg plus simvastatin 20 mg daily vs placebo). The key outcome will be major atherosclerotic events, defined as the combination of myocardial infarction, coronary death, ischemic stroke, or any revascularization procedure.RESULTS: A total of 9,438 CKD patients were randomized, of whom 3,056 were on dialysis. Mean age was 61 years, two thirds were male, one fifth had diabetes mellitus, and one sixth had vascular disease. Compared with either placebo or simvastatin alone, allocation to ezetimibe plus simvastatin was not associated with any excess of myopathy, hepatic toxicity, or biliary complications during the first year of follow-up. Compared with placebo, allocation to ezetimibe 10 mg plus simvastatin 20 mg daily yielded average LDL cholesterol differences of 43 mg/dL (1.10 mmol/L) at 1 year and 33 mg/dL (0.85 mmol/L) at 2.5 years. Follow-up is scheduled to continue until August 2010, when all patients will have been followed for at least 4 years.CONCLUSIONS: SHARP should provide evidence about the efficacy and safety of lowering LDL cholesterol with the combination of ezetimibe and simvastatin among a wide range of patients with CKD.</p
Study of Heart and Renal Protection (SHARP): Randomized trial to assess the effects of lowering low-density lipoprotein cholesterol among 9,438 patients with chronic kidney disease
SemCW: Semantic Collaborative Writing using RST
During collaborative writing each author works on a copy of the shared document. These copies are then merged to produce the final document. This asynchronous work is supported by several collaborative writing tools. While these tools are excellent at merging and detecting syntactic conflicts, they are not able to easily recognise semantic inconsistencies. This hinders the coherence of the document because while each individual copy might be well constructed, they may not be after the merge. To address this, we investigate the combination of the Rhetorical Structure Theory with Operational Transformation approach. In this paper, we define a data model, a set of operations to manipulate the RST structures and a set of transformation functions. A validity checker alerts the authors to areas in the text with possible semantic lapses in the merged documents
A narrative-based collaborative writing tool for coherent technical documents
One important feature of an effective document that makes it easy to read and understand is known as coherence. Technical documents produced collaboratively are often incoherent due to a lack of group consensus and misaligned contributions by the individual authors. However, current document planning techniques and writing tools do not provide explicit support for improving coherence. The goal of this research, therefore, is to develop and evaluate a new technique and tool that helps teams of authors to structure coherent technical documents. The coherence of a document can be attributed to the story (or narrative) it conveys to the reader. If this story is consistent and coherent, the same can be said about the document. A discourse theory such as Rhetorical Structure Theory (RST) that has been developed by linguists helps further to analyse and improve a narrative. RST explains the coherence of a text by virtue of relationships (such as “paragraph A justifies paragraph B”) between parts of the text. This research has combined the ideas from these parallel strands of research to develop a new document planning technique called narrative-based writing. The method involves writing down an explicit précis of the story (called a document narrative or DN) and then analysing it using RST. The DN and RST analysis are then used to structure the eventual document. To extend the usability of narrative-based writing to geographically-dispersed authors, I have designed and implemented a collaborative tool that allows co-authors to edit, analyse and review DNs. The thorough design for the tool uses a combination of three models (conceptual, business process and functional) culminating in a set of functions that enable collaborative narrative-based writing. This dissertation discusses how, in the future, these functions could be incorporated in existing collaborative writing tools. Implementing this tool, albeit in its current prototypic state, has been invaluable in understanding the complexities of modelling and manipulating DNs and RST structures. Initial investigations using the new technique and tool have been positive, encouraging me to continue the research and evaluation in this field
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