城市高密度人口分布下的社区建设——以广州荔湾区为例

以广州荔湾区“六普”资料为根据，就人口高密度分布与社区建设的关系进行梳理与探讨。荔湾区“六普”数据显示，城区人口密度过高，成为影响社区生活的主要因素，给居民生命安全、公共生活质量与日常生活便利性带来负面效应。科学化与人性化人口密度干预是治理高密度人口问题的理性策略，如“跳出”社区视野，在城市“一盘棋”中均衡人口布局，在社区建设中，通过社区更新改造，增强人口承载能力，通过建构便利舒适人居环境，提升社区生活质量。     

基于同城化视角的人口空间动态与区域经济发展耦合关联机理研究

人口空间动态与区域经济发展的耦合关系是同城化区域间共同面对的重要课题。本文在解构人口空间动态维度主体的基础上,将人口空间动态的诉求机制与动因机理架构于更低交易费用的利益诉求之上,解析人口空间动态的模式选择,深入探讨人口空间动态与区域经济发展的耦合关联性。在此基础上,提出引导人口流动与合理分布的策略。研究成果将有助于更好地理解同城化态势下人口空间演变的动因机理,为同城区域的经济发展、城市规划、文化交融等方面的科学设计提供重要参考。     

铁路总价承包合同管理存在的主要问题及对策

结合我国铁路总价承包合同执行现状，对铁路合同专用条款中存在的承发包双方法律地位不对等、工程款拨付比例不切实际、总承包风险费严重不足等主要不合理内容进行剖析，说明不合理的原因。对发包人处理正负量差的方式、工期调整产生的赶工费不能全额解决及部分变更设计在源头上得不到认可等在合同执行过程中存在的问题进行研究。简单分析产生不合理条款和合同执行不到位的主要原因。针对这些不合理条款，提出应对策略。     

Heterogeneity in treatment effects across diverse populations

Differences in patient characteristics, including age, sex, and race influence the safety and effectiveness of drugs, biologic products, and medical devices. Here we provide a summary of the topics discussed during the opening panel at the 2018 Johns Hopkins Center for Excellence in Regulatory Science and Innovation symposium on Assessing and Communicating Heterogeneity of Treatment Effects for Patient Subpopulations: Challenges and Opportunities. The goal of this session was to provide a brief overview of FDA-regulated therapeutics, including drugs, biologics and medical devices, and some of the major sources of heterogeneity of treatment effects (HTE) related to patient demographics, such as age, sex and race. The panel discussed the US Food and Drug Administration's role in reviewing and regulating drugs, devices, and biologic products and the challenges associated with ensuring that diverse patient populations benefit from these therapeutics. Ultimately, ensuring diverse demographic inclusion in clinical trials, and designing basic and clinical research studies to account for the intended patient population's age, sex, race, and genetic factors among other characteristics, will lead to better, safer therapies for diverse patient populations.     

西北五省经济人口承载力的分析及预测

对于中国这个人口大国,人口承载力是一个值得研究和关注的课题,西北五省在人们的印象中是地广人稀,学界对该地区的人口承载力的研究大都从自然资源的角度探讨,然而本文不考虑自然因素的作用,认为一个区域资源的稀缺可以通过经济技术解决,只是成本高低的问题,因此仅从经济人口承载力的角度分析,利用P-E-R模型分析西北五省人口承载力,并利用ARIMA模型对2012-2015年该地区人口承载力进行预测,并得出相关结论.     

Rare and clustered population estimation using the adaptive cluster sampling with some robust measures

The use of robust measures helps to increase the precision of the estimators, especially for the estimation of extremely skewed distributions. In this article, a generalized ratio estimator is proposed by using some robust measures with single auxiliary variable under the adaptive cluster sampling (ACS) design. We have incorporated tri-mean (TM), mid-range (MR) and Hodges-Lehman (HL) of the auxiliary variable as robust measures together with some conventional measures. The expressions of bias and mean square error (MSE) of the proposed generalized ratio estimator are derived. Two types of numerical study have been conducted using artificial clustered population and real data application to examine the performance of the proposed estimator over the usual mean per unit estimator under simple random sampling (SRS). Related results of the simulation study show that the proposed estimators provide better estimation results on both real and artificial population over the competing estimators.     

基于委托代理理论的会计信息失真问题研究

会计信息失真问题越演越烈,并且已成为一个世界性难题。可靠性、真实性、相关性是会计信息质量的生命,但一系列会计舞弊行为的发生已篡改了会计信息的本来面目,会计信息"诚信工程"摇摇欲坠。造成会计信息失真的原因有很多,就此,我国也采取了相应的措施予以治理,但效果并不显著,往往是治标不治本。本文从产生会计信息失真问题的根源出发,重点剖析了在以委托代理理论为根基的现代股份制企业中会计信息失真的原因,并提出了提高委托代理制度下的会计信息质量的相应对策。     

解决信访问题的有效性对策——基于对H市信访问题特点的分析

信访问题能够反映不同时期、不同治理状态下的政府行为对相对人的影响，信访问题呈现的新特点能凸显公民的利益诉求方向，解决信访问题的有效性对策正是要解决根源性问题，加强源头治理，规范政府行为，强化各级政府社会管理的主体意识、担当意识和责任意识；健全信访制度体系，推进建立信访预警研判机制。     

陕西省人口城市化Logistic模型及其应用——基于结构突变的理论分析

城市化是走向现代化的必经阶段,准确的城市化预测是进行经济、社会建设的基础。在结构突变理论的基础上,用Logistic模型对1978～2010年陕西城市化率进行分析。结论表明：1999年为陕西城市化率的结构突变点,说明城市化率的增长受到外部冲击的影响,分段以后的拟合优度明显提高。分别以阈值0.8和1进行分阶段构建的Logistic拟合精度明显提高,但阈值为1的精度更高,说明陕西城市化还在加速,预测表明到2030年陕西城市化率将达到70%左右。总体而言,从1984年到2030年为陕西省城市化的加速阶段。城市化加速阶段的住房问题、人口膨胀、环境恶化、交通拥挤、社会治安问题必须妥善解决。     

Assessing respondent-driven sampling: A simulation study across different networks

The purpose was to assess RDS estimators in populations simulated with diverse connectivity characteristics, incorporating the putative influence of misreported degrees and transmission processes. Four populations were simulated using different random graph models. Each population was “infected” using four different transmission processes. From each combination of population x transmission, one thousand samples were obtained using a RDS-like sampling strategy. Three estimators were used to predict the population-level prevalence of the “infection”. Several types of misreported degrees were simulated. Also, samples were generated using the standard random sampling method and the respective prevalence estimates, using the classical frequentist estimator. Estimation biases in relation to population parameters were assessed, as well as the variance. Variability was associated with the connectivity characteristics of each simulated population. Clustered populations yield greater variability and no RDS-based strategy could address the estimation biases. Misreporting degrees had modest effects, especially when RDS estimators were used. The best results for RDS-based samples were observed when the “infection” was randomly attributed, without any relation with the underlying network structure.