1,366 research outputs found

    Prediction of Large Events on a Dynamical Model of a Fault

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    We present results for long term and intermediate term prediction algorithms applied to a simple mechanical model of a fault. We use long term prediction methods based, for example, on the distribution of repeat times between large events to establish a benchmark for predictability in the model. In comparison, intermediate term prediction techniques, analogous to the pattern recognition algorithms CN and M8 introduced and studied by Keilis-Borok et al., are more effective at predicting coming large events. We consider the implications of several different quality functions Q which can be used to optimize the algorithms with respect to features such as space, time, and magnitude windows, and find that our results are not overly sensitive to variations in these algorithm parameters. We also study the intrinsic uncertainties associated with seismicity catalogs of restricted lengths.Comment: 33 pages, plain.tex with special macros include

    Is attributing smoking to genetic causes associated with a reduced probability of quit attempt success? A cohort study

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    AIMS: Pharmacogenetic smoking cessation interventions would involve smokers being given information about the influence of genes on their behaviour. However, attributing smoking to genetic causes may reduce perceived control over smoking, reducing quit attempt success. This study examines whether attributing smoking to genetic influences is associated with reduced quitting and whether this effect is mediated by perceived control over smoking. DESIGN: Cohort study. PARTICIPANTS: A total of 792 smokers, participating in a trial of nicotine replacement therapy (NRT)-assisted smoking cessation. Participants were informed that the trial investigated relationships between genetic markers and smoking behaviour, but personalized genetic feedback was not provided. SETTING: Primary care in Oxfordshire and Buckinghamshire, UK. MEASUREMENTS: Perceived control over smoking and perceived importance of genetic factors in causing smoking assessed pre-quit; abstinence 4, 12, 26 and 52 weeks after the start of treatment. FINDINGS: A total of 515 smokers (65.0%) viewed genetic factors as playing some role in causing their smoking. They had lower perceived control over smoking than smokers who viewed genetic factors as having no role in causing their smoking. Attributing smoking to genetic causes was not associated significantly with a lower probability of quit attempt success. CONCLUSIONS: Attributing smoking to genetic factors was associated with lower levels of perceived control over smoking but not lower quit rates. This suggests that learning of one's genetic predisposition to smoking during a pharmacogenetically tailored smoking cessation intervention may not deter quitting. Further research should examine whether the lack of impact of genetic attributions on quit attempt success is also found in smokers provided with personalized genetic feedback

    A transatlantic perspective on 20 emerging issues in biological engineering

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    Advances in biological engineering are likely to have substantial impacts on global society. To explore these potential impacts we ran a horizon scanning exercise to capture a range of perspectives on the opportunities and risks presented by biological engineering. We first identified 70 potential issues, and then used an iterative process to prioritise 20 issues that we considered to be emerging, to have potential global impact, and to be relatively unknown outside the field of biological engineering. The issues identified may be of interest to researchers, businesses and policy makers in sectors such as health, energy, agriculture and the environment

    Difficult Decisions: A Qualitative Exploration of the Statistical Decision Making Process from the Perspectives of Psychology Students and Academics.

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    Quantitative research methods are essential to the development of professional competence in psychology. They are also an area of weakness for many students. In particular, students are known to struggle with the skill of selecting quantitative analytical strategies appropriate for common research questions, hypotheses and data types. To begin understanding this apparent deficit, we presented nine psychology undergraduates (who had all completed at least one quantitative methods course) with brief research vignettes, and asked them to explicate the process they would follow to identify an appropriate statistical technique for each. Thematic analysis revealed that all participants found this task challenging, and even those who had completed several research methods courses struggled to articulate how they would approach the vignettes on more than a very superficial and intuitive level. While some students recognized that there is a systematic decision making process that can be followed, none could describe it clearly or completely. We then presented the same vignettes to 10 psychology academics with particular expertise in conducting research and/or research methods instruction. Predictably, these "experts" were able to describe a far more systematic, comprehensive, flexible, and nuanced approach to statistical decision making, which begins early in the research process, and pays consideration to multiple contextual factors. They were sensitive to the challenges that students experience when making statistical decisions, which they attributed partially to how research methods and statistics are commonly taught. This sensitivity was reflected in their pedagogic practices. When asked to consider the format and features of an aid that could facilitate the statistical decision making process, both groups expressed a preference for an accessible, comprehensive and reputable resource that follows a basic decision tree logic. For the academics in particular, this aid should function as a teaching tool, which engages the user with each choice-point in the decision making process, rather than simply providing an "answer." Based on these findings, we offer suggestions for tools and strategies that could be deployed in the research methods classroom to facilitate and strengthen students' statistical decision making abilities

    The Myth of Clean Sport and its Unintended Consequences

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    Anti-doping has long been premised on the myth of clean sport, a consistent vision that has survived changes in the social and cultural environment. This article starts with a discussion of the meaning of clean sport focusing on the gap between this idealisation and practice. It then traces the historical emergence of this myth, briefly explaining its cultural foundations, and its influence on in-competition drug testing development in the 1960s. It will be argued that clean sport only made sense when the focus was on in-competition use of stimulants. The emergence of drugs such as steroids, used out of competitions, created a conflict between the reality of doping practices and the mythical past and future idealisation of sport as clean. Nonetheless anti-doping leaders maintained their public position that testing systems could defeat doping practices. Due to the continuity of ethical ideas, the construction of health fears, and public scandals, the World Anti-Doping Agency pressed on with, and was empowered by, the absolutist clean sport vision leading to the conceptually flawed, contradictory, draconian and problematic policy environment we face today

    Introducing StatHand: A Cross-Platform Mobile Application to Support Students' Statistical Decision Making

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    Although essential to professional competence in psychology, quantitative research methods are a known area of weakness for many undergraduate psychology students. Students find selecting appropriate statistical tests and procedures for different types of research questions, hypotheses and data types particularly challenging, and these skills are not often practiced in class. Decision trees (a type of graphic organizer) are known to facilitate this decision making process, but extant trees have a number of limitations. Furthermore, emerging research suggests that mobile technologies offer many possibilities for facilitating learning. It is within this context that we have developed StatHand, a free cross-platform application designed to support students' statistical decision making. Developed with the support of the Australian Government Office for Learning and Teaching, StatHand guides users through a series of simple, annotated questions to help them identify a statistical test or procedure appropriate to their circumstances. It further offers the guidance necessary to run these tests and procedures, then interpret and report their results. In this Technology Report we will overview the rationale behind StatHand, before describing the feature set of the application. We will then provide guidelines for integrating StatHand into the research methods curriculum, before concluding by outlining our road map for the ongoing development and evaluation of StatHand

    Potential for anthropogenic disturbances to influence evolutionary change in the life history of a threatened salmonid

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    Although evolutionary change within most species is thought to occur slowly, recent studies have identified cases where evolutionary change has apparently occurred over a few generations. Anthropogenically altered environments appear particularly open to rapid evolutionary change over comparatively short time scales. Here, we consider a Pacific salmon population that may have experienced life-history evolution, in response to habitat alteration, within a few generations. Historically, juvenile fall Chinook salmon (Oncorhynchus tshawytscha) from the Snake River migrated as subyearlings to the ocean. With changed riverine conditions that resulted from hydropower dam construction, some juveniles now migrate as yearlings, but more interestingly, the yearling migration tactic has made a large contribution to adult returns over the last decade. Optimal life-history models suggest that yearling juvenile migrants currently have a higher fitness than subyearling migrants. Although phenotypic plasticity likely accounts for some of the change in migration tactics, we suggest that evolution also plays a significant role. Evolutionary change prompted by anthropogenic alterations to the environment has general implications for the recovery of endangered species. The case study we present herein illustrates the importance of integrating evolutionary considerations into conservation planning for species at risk
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