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关键词： 交叉设计   临床试验设计   统计研究设计   自身配对设计   概要说明   正交设计   成组设计   实验设计  

摘要： 1.统计研究设计:应交代统计研究设计的名称和主要做法。如调查设计(分为前瞻性、冋顾性或横断面调查研究);实验设计(应交代具体的设计类型,如自身配对设计、成组设计、交叉设计、正交设计等);临床试验设计(应交代属于第几期临床试验,采用了何种盲法措施等)。主要做法应围绕4个基本原则(随机、对照、重复、均衡)概要说明,尤其要交代如何控制重要非试验因素的干扰和影响.

关键词： 算术平均数   检验值   卡方检验   F检验   英文大写   希文   t检验   统计学符号  

摘要： 按照国家标准GB3358-82《统计学名词及符号》的有关规定书写,常用如下:(1)样本的算术平均数用英文小写 (中位数仍用M);(2)标准差用英文小写s;(3)标准误用英文小写Sx;(4)t检验用英文小写t;(5)F检验用英文大写F;(6)卡方检验用希文小写χ^(2);(7)相关系数用英文小写r;(8)自由度用希文小写μ;(9)概率用英文大写P(P值前应给出具体检验值,如t值、χ^(2)值、q值等)。以上符号均用斜体。

关键词： 高职院校   统计数据   教学  

摘要： 高职经济管理专业一般开设统计课程,即基础课。创造性地解决问题,简化知识,提高学生的专业技能和考试技能,对教师来说具有重要意义。本文从教学方法、教学方法、教学工具等方面对相关问题进行了探讨,并提出了相应的对策,以期为同行提供指导和借鉴。

关键词： 专业论文   算术平均数   统计学符号   t检验   中位数   斜体   标准差   小写  

摘要： 专业论文中有关统计学符号的使用,需按照国家标准GB3358-82《统计学名词及符号》的规定,符号一律用斜体表达。样本的算术平均数用小写x,不能使用大写X,也不能用M(以免与中位数混淆)。标准差用s,而不用SD。标准误用Sx,不用SE,也不用SEM。t检验用小写斜体t。

关键词： Demographic economics   Pandemics   Age-adjusted mortality   Spanish flu   Covid-19   Ireland  

摘要： Using the Irish experience of the 1918-1919 Spanish flu pandemic ("Influenza-18"), we demonstrate how pandemic mortality statistics can be sensitive to the demographic composition of a country. We build a new spatially disaggregated population database for Ireland's 32 counties for 1911-1920 with vital statistics on births, ageing, migration and deaths. Our principal contribution is to show why, and how, age-at-death data should be used to construct the age-standardised statistics necessary to make meaningful comparisons of mortality rates across time and space. We conclude that studies of the economic consequences of pandemics must better control for demographic factors if they are to yield useful policy-relevant insights. For example, while Northern Ireland had a higher crude death rate during the first wave of the Covid-19 pandemic, it also has an older population;age-adjusted mortality paints a very different picture. (c) 2021 Elsevier B.V. All rights reserved.

关键词： 统计学  

ISBN: (纸本)9787030685025

摘要： 本书兼顾抽样技术和试验设计的知识完整性和相对独立性，突出内容通俗性和实际应用性，主要选择简单随机抽样、分层随机抽样、两级抽样等抽样技术内容，以及单因子试验、两因子试验、随机化区组试验、正交设计、最优设计、计算机试验设计等试验设计内容。本书注重讲解代表性的理论方法和模型，回避烦琐的理论性质的解释和证明，并易于计算机软件操作。为了演示抽样技术和试验设计的理论方法，本书编写统计案例，演示如何应用统计方法解决实际问题，便于读者的理解和自学。

关键词： camera trapping   demographic survival   Elephas maximus   habitat fragmentation   People&apos   s Republic of China   population thresholds   protected areas   Yunnan Province  

摘要： The Asian elephant Elephas maximus is at risk of extinction as a result of anthropogenic pressures, and remaining populations are often small and fragmented remnants, occupying a fraction of the species' former range. Once widely distributed across China, only a maximum of 245 elephants are estimated to survive across seven small populations. We assessed the Asian elephant population in Nangunhe National Nature Reserve in Lincang Prefecture, China, using camera traps during May-July 2017, to estimate the population size and structure of this genetically important population. Although detection probability was low (0.31), we estimated a total population size of c. 20 individuals, and an effective density of 0.39 elephants per km(2). Social structure indicated a strong sex ratio bias towards females, with only one adult male detected within the population. Most of the elephants associated as one herd but three adult females remained separate from the herd throughout the trapping period. These results highlight the fragility of remnant elephant populations such as Nangunhe and we suggest options such as a managed metapopulation approach for their continued survival in China and more widely.

关键词： International migration   Migration prospects   World economy   Inequality  

摘要： This paper sheds light on the global migration patterns of the past 40 years, and produces migration projections for the 21st century. To do this, we build a simple model of the world economy, and we parameterize it to match the economic and socio-demographic characteristics of the world in the year 2010. We conduct backcasting and nowcasting exercises, which demonstrate that our model fits very well the past and ongoing trends in international migration, and that historical trends were mostly governed by demographic changes. Then, we describe a set of migration projections for the 21st century. In line with the backcasts, our world migration prospects are mainly governed by socio-demographic changes. Using immigration restrictions or development policies to curb these pressures requires sealing borders or triggering unprecedented economic takeoffs in migrants' countries of origin. Increasing migration is thus a likely phenomenon for the 21st century.

关键词： demography   Gopherus polyphemus   hierarchical model   mark‐   recapture analysis   minimum viable population   population structure   population viability analysis   survival  

摘要： Population viability analyses are useful tools to predict abundance and extinction risk for imperiled species. In southeastern North America, the federally threatened gopher tortoise (Gopherus polyphemus) is a keystone species in the diverse and imperiled longleaf pine (Pinus palustris) ecosystem, and researchers have suggested that tortoise populations are declining and characterized by high extinction risk. We report results from a 30-year demographic study of gopher tortoises in southern Alabama (1991-2020), where 3 populations have been stable and 3 others have declined. To better understand the demographic vital rates associated with stable and declining tortoise populations, we used a multi-state hierarchical mark-recapture model to estimate sex- and stage-specific patterns of demographic vital rates at each population. We then built a predictive population model to project population dynamics and evaluate extinction risk in a population viability context. Population structure did not change significantly in stable populations, but juveniles became less abundant in declining populations over 30 years. Apparent survival varied by age, sex, and site;adults had higher survival than juveniles, but female survival was substantially lower in declining populations than in stable ones. Using simulations, we predicted that stable populations with high female survival would persist over the next 100 years but sites with lower female survival would decline, become male-biased, and be at high risk of extirpation. Stable populations were most sensitive to changes in apparent survival of adult females. Because local populations varied greatly in vital rates, our analysis improves upon previous demographic models for northern populations of gopher tortoises by accounting for population-level variation in demographic patterns and, counter to previous model predictions, suggests that small tortoise populations can persist when habitat is managed effectively. (c) 2021 The Wildl

关键词： Particle swap optimization   Quantitative lung fibrosis   Machine learning   Random forest   Medical image  

摘要： Background: Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease characterized by an unpredictable decline in lung function. Predicting IPF progression from the early changes in lung function tests have known to be a challenge due to acute exacerbation. Although it is unpredictable, the neighboring regions of fibrotic reticulation increase during IPF's progression. With this clinical information, quantitative characteristics of high-resolution computed tomography (HRCT) and a statistical learning paradigm, the aim is to build a model to predict IPF progression. Design: A paired set of anonymized 193 HRCT images from IPF subjects with 6-12 month intervals were collected retrospectively. The study was conducted in two parts: (1) Part A collects the ground truth in small regions of interest (ROIs) with labels of "expected to progress" or "expected to be stable" at baseline HRCT and develop a statistical learning model to classify voxels in the ROIs. (2) Part B uses the voxel-level classifier from Part A to produce whole-lung level scores of a single-scan total probability's (STP) baseline. Methods: Using annotated ROIs from 71 subjects' HRCT scans in Part A, we applied Quantum Particle Swarm Optimization-Random Forest (QPSO-RF) to build the classifier. Then, 122 subjects' HRCT scans were used to test the prediction. Using Spearman rank correlations and survival analyses, we ascertained STP associations with 6-12 month changes in quantitative lung fibrosis and forced vital capacity. Conclusion: This study can serve as a reference for collecting ground truth, and developing statistical learning techniques to predict progression in medical imaging.