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监测数据统计分析模型在生态学研究中的应用   总被引:1,自引:1,他引:0       下载免费PDF全文
近年来,环境监测、疾病监测等各种监测网络不断健全,监测系统成为开展生态学研究的重要数据来源。监测数据类型包括了横断面数据、时间序列数据和面板数据,涉及暴露、结局和混杂3个维度。针对该数据的信息属性和结构特点,相关统计学方法逐渐发展完善,出现了一些新的方法、模型。基于数据的时空属性,本文对监测数据在生态学研究中常用模型的原理、适用条件及优劣进行了综述。  相似文献   
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A long‐standing question in child language research concerns how children achieve mature syntactic knowledge in the face of a complex linguistic environment. A widely accepted view is that this process involves extracting distributional regularities from the environment in a manner that is incidental and happens, for the most part, without the learner's awareness. In this way, the debate speaks to two associated but separate literatures in language acquisition: statistical learning and implicit learning. Both fields have explored this issue in some depth but, at present, neither the results from the infant studies used by the statistical learning literature nor the artificial grammar learning tasks studies from the implicit learning literature can be used to fully explain how children's syntax becomes adult‐like. In this work, we consider an alternative explanation—that children use error‐based learning to become mature syntax users. We discuss this proposal in the light of the behavioral findings from structural priming studies and the computational findings from Chang, Dell, and Bock's (2006) dual‐path model, which incorporates properties from both statistical and implicit learning, and offers an explanation for syntax learning and structural priming using a common error‐based learning mechanism. We then turn our attention to future directions for the field, here suggesting how structural priming might inform the statistical learning and implicit learning literature on the nature of the learning mechanism.  相似文献   
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目的 分析河南省疾病预防控制中心2005 - 2017年科技论文发表情况,为疾控机构今后科研工作发展、学科建设和人才队伍建设提供参考依据。方法 运用中国知网、万方数据库、Pubmed、EMbase、Web of Science数据库或搜索引擎,检索2005 - 2017年“第一作者”当时是该中心员工且“第一作者单位”为“该中心”正式发表的科技论文,应用Microsoft Exce 2010录入和整理数据,应用SPSS 17.0软件进行统计分析。结果 2005 - 2017年该机中心发表科技论文2 052篇,年平均发表158篇。刊载在200种期刊上,其中外文期刊37种,中文期刊163种。传染病防控专业和卫生检验专业发表的论文数量占比较高,分别为45.18%和23.73%。CN一般期刊占比最高,为44.44%;其次是中文核心期刊,为40.59%。硕士、博士学历组人均发表论文较多,人均分别为12.09篇、12.82篇;副高和正高级职称组人均发表论文较多,分别为12.36篇、10.76篇,结论 该中心近年年均发表论文数量和质量整体呈上升趋势,在国内同行中处于相对较高水平,说明科研水平在稳步上升,同时也反映出社会影响、政策激励对科学研究的推动作用。  相似文献   
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目的 应用统计过程控制方法对加速器日质控(QC)数据进行分析,并对使用晨检仪的QC过程进行评估。方法 加速器、晨检仪校准后分别收集由技师、物理师摆位的100组、30组QC数据,设备第2次校准后再次收集技师摆位的QC数据100组,分析两次校准后技师摆位数据(各100组)的归一化信噪比的变化规律。使用由技师和物理师摆位的QC数据(各30组)绘制控制图,比较中心线位置和上下控制线范围的不同。计算由技师、物理师摆位的3个组日QC的过程能力指数。结果 两次校准的技师摆位数据归一化信噪比均为前6周变化较大,6~8周后趋于稳定,8周后逐渐变小。物理师摆位的QC数据在输出量一致性方面,上下控制线范围更窄;在平坦度、对称性方面,中心线更接近目标值0。对输出量一致性、平坦度方面,3个组日QC的过程能力指数均满足≥1要求;对称性Transverse方向均不满足。结论 应采用30~40个数据点绘制加速器日QC过程的控制图。QC过程应由相对固定且较少的QC人员完成,检测项目也应设置更适合的容差。  相似文献   
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《Vaccine》2020,38(18):3501-3507
BackgroundNo national vaccination program against herpes zoster (HZ) is currently in place in Norway. We aimed to quantify the burden of medically attended HZ to assess the need for a vaccination program.MethodsWe linked data from several health registries to identify medically attended HZ cases during 2008–2014 and HZ-associated deaths during1996–2012 in the entire population of Norway. We calculated HZ incidences for primary and hospital care by age, sex, type of health encounter, vaccination status, and co-morbidities among hospital patients. We also estimated HZ-associated mortality and case-fatality.ResultsThe study included 82,064 HZ patients, of whom none were reported as vaccinated against HZ. The crude annual incidence of HZ was 227.1 cases per 100,000 in primary healthcare and 24.8 cases per 100,000 in hospitals. Incidence rates were higher in adults aged ≥50 years (461 per 100,000 in primary care and 57 per 100,000 in hospitals), and women than in men both in primary healthcare (267 vs 188 per 100,000), and hospitals (28 vs 22 per 100,000). Among hospital patients, 47% had complicated zoster and 25% had comorbidities, according to the Charlson comorbidity index. The duration of hospital stay (median 4 days) increased with the severity of comorbidities. The estimated mortality rate was 0.18 per 100,000; and in-hospital case-fatality rate was 1.04%.ConclusionsMedically attended HZ poses a substantial burden in the Norwegian healthcare sector. The majority of the zoster cases occurred among adults aged ≥50 years – the group eligible for zoster vaccination – and increased use of zoster vaccination may be warranted, especially among persons with co-morbidities.  相似文献   
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BackgroundCoordination variability has been linked to overuse running injuries and has been studied both on a treadmill and over-ground. It is not clear, however, if the coordination variability data from over-ground locomotion can be compared with treadmill locomotion data.Research questionTherefore, the purpose of this study was to compare coordination variability of selected lower extremity couplings at different locomotor speeds during over-ground and treadmill walking and running.MethodsNineteen (10 female, 9 male) healthy, recreational collegiate runners participated in this study. Each participant performed in two different conditions: over-ground and on a treadmill at three walking speeds (1.2, 1.6, and 2.0 m•s−1) and three running speeds (2.8, 3.2, and 3.6 m•s−1). A modified vector coding technique was used to calculate coordination variability for five selected coupled segment and joint angles. Each of the segmental couples was analyzed separately using a two-way repeated measures ANOVA (Condition Χ Speed) implemented with one-dimensional statistical parametric mapping.ResultsWhile no interaction effects were observed for condition X speed, we saw increased coordination variability in the sagittal couples during overground compared with treadmill locomotion, which predominantly occurred during the stance phase. There were mixed results for changes in coordination variability as a function of gait speed. However, for the sagital plane couplings, coordination variability decreased with speed, particularly during the stance phase.SignificanceThese results suggest that the controlled belt speed of the treadmill affects the intrinsic dynamics of human movement and this should be considered when making comparisons between treadmill and over-ground studies and in future study designs.  相似文献   
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