Bayesian modelling of catch in a north-west Atlantic fishery

Summary. We model daily catches of fishing boats in the Grand Bank fishing grounds. We use data on catches per species for a number of vessels collected by the European Union in the context of the Northwest Atlantic Fisheries Organization. Many variables can be thought to influence the amount caught: a number of ship characteristics (such as the size of the ship, the fishing technique used and the mesh size of the nets) are obvious candidates, but one can also consider the season or the actual location of the catch. Our database leads to 28 possible regressors (arising from six continuous variables and four categorical variables, whose 22 levels are treated separately), resulting in a set of 177 million possible linear regression models for the log-catch. Zero observations are modelled separately through a probit model. Inference is based on Bayesian model averaging, using a Markov chain Monte Carlo approach. Particular attention is paid to the prediction of catches for single and aggregated ships.     

浅谈中小学合唱教学

本文通过对童声合唱艺术的重要性与训练中若干技术问题的分析 ,结合我国中小学音乐教育的实际状况而进行思考 ,认为在我国中小学音乐教育中 ,合唱教学应该占据与其地位相适应的位置 ;在合唱教学的具体实施中 ,要让中小学学生在曲目上有多样性的选择空间 ,以适应其生理与心理特点 ;学生所学的音乐知识应在合唱训练中得到全面的实践 ,从而使学生的艺术修养得到全面提升     

DELPHI中图形的连续旋转与动画的实现

阐述了在DELPHI语言中利用Canvas的Pixels[]属性来实现图形连续旋转和利用CopyRect()函数实现动画的方法 .     

论官德建设

本文论述了官德建设是我国历代治国方略中的优秀传统 ,阐述了官德建设在以德治国中的重要地位 ,提出了在新形势下构建官德建设的办法和措施     

魏晋论说文文论探析

三国时期的论说文文论以谋求论说文独立的文学地位为指　向　。批评家们不但树立了“理”的旗帜来对抗“经”的禁锢，而且意识到了文采的价值和作家　独特的修养。晋代论说文文论较前一时期有了长足的进步。批评家数量增多，研究方法得到　改进，人们或从“辞”、“理”兼顾的角度，或从形式技巧的角度，肯定了许多风格各异的　作品。同时，汉代以来的旧观念在上述两个时期与新的见解还有所交织。     

纪念邓小平《党和国家领导制度的改革》发表22周年

本文重温邓小平同志１９８０年８月关于《党和国家领导制度的改革》的讲话，概括指出：一、其三个方面的内容：实行党政分开；适当分权；改革干部人事制度。二、政治体制改革的原则方针：改革必须坚持社会主义方向；改革必须要有利于坚持和加强党的领导。三、政治体制改革的目标取向：发展社会主义民主，走民主的制度化、法制化道路。深刻领会该讲话精神，对于推动我国新世纪的政治体制改革具有重要的理论意义和现实意义。     

要理直气壮地进行共产主义理想教育

应用SPSS10.0统计软件对我校学前教育专业98级44名学生的18门课程成绩进行了因素分析，据此探讨学前教育专业学生的能力结构，并对该专业的课程设置和改革提供若干建议。     

Empirical likelihood confidence intervals for the mean of a population containing many zero values

If a population contains many zero values and the sample size is not very large, the traditional normal approximation‐based confidence intervals for the population mean may have poor coverage probabilities. This problem is substantially reduced by constructing parametric likelihood ratio intervals when an appropriate mixture model can be found. In the context of survey sampling, however, there is a general preference for making minimal assumptions about the population under study. The authors have therefore investigated the coverage properties of nonparametric empirical likelihood confidence intervals for the population mean. They show that under a variety of hypothetical populations, these intervals often outperformed parametric likelihood intervals by having more balanced coverage rates and larger lower bounds. The authors illustrate their methodology using data from the Canadian Labour Force Survey for the year 2000.     

烹调油烟的免疫毒理学研究进展

烹调油烟是室内主要空气污染物之一，化学成分复杂，严重影响职业接触人群的健康．对烹调油烟免疫毒性的研究是全面评价其毒性作用的一个重要方面．对近几年来烹调油烟影响机体细胞免疫、体液免疫和巨噬细胞以及NK细胞功能等免疫毒性方面的研究进展作一综述．     

Type I error rates from likelihood‐based repeated measures analyses of incomplete longitudinal data

The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SE_Δ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SE_Δ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SE_Δ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.