Optimal Bayesian Randomization

Randomization is a puzzle for Bayesians. The intuitive need for randomization is clear, but there is a standard result that Bayesians need not randomize. In this paper we propose a model in which randomization is a strictly optimal procedure. The most important aspect of our model is that there are several parties who make different decisions and observe different data. The result also sheds light on the ethical considerations involving randomization in a clinical trial.     

中国农户收入增长与就业决策行为：一个动态解释—基于湖北农户跟踪调查的实证研究

 本文围绕着农户家庭收入增长和劳动就业决策行为的动态关系而展开，笔者在设定一个基本理论框架的基础上提出了两个基本假说，进而引出了经验分析。本项研究利用2001—2006年湖北15个村庄的900户农户跟踪调查的面板数据，研究发现：（1）农户家庭是一个理性的微观经济组织。（2）处于外生政策变动中的农户经济组织是一个完整的经济系统，它在外部经济条件的冲击下表现出比较稳定的“状态依赖”特征。当前中国农村形成了“农村就业两端刚性”的趋势。（3）从短期来看，外部支农政策冲击并没有从本质上改变农户家庭的就业决策行为。（4）中国农村家庭就业行为决策是本质上的理性和表现上的非理性的统一。     

荥阳战略地理分析

荥阳历来就是军事要地,自先秦以来,此地就是战争频仍之地;楚汉战争中,荥阳地区的战事对战争的最终结局有重要影响;汉朝建立后,荥阳地区在控制关东与保障关中安全方面有重大作用。     

谈对青年教师的“传帮带”

针对课程特点,结合多年的教学经验,总结论述了"机械制图"课程教学中,如何对青年教师传帮带的一些做法和体会,意在对理工科专业基础课和专业课青年教师的培养起到借鉴作用。     

我国地方政府户籍制度改革的案例比较分析

在中央稳妥推进户籍制度改革的总要求下,各地户籍制度改革的力度及方式并不相同,其效果也呈现较大差别。对地方户籍制度改革的典型实践做出对比分析,有助于认识各地户籍制度改革实践的优劣及户籍制度改革应遵循的一般规律,从而为中国的户籍制度改革提供理论借鉴和现实参考。基于此,选取成都、重庆、郑州、中山4个城市的户籍改革案例进行比较研究,从改革措施、改革绩效等方面进行对比分析。认为现有地方政府户籍制度改革的自利性倾向较强,以人为本的价值理性诉求较为缺失。因此,要推进以“人”的城镇化为核心的户籍制度改革,同时降低户籍制度改革的相关风险,地方政府应充分尊重转户者意愿,并严格执行城市分类管理原则,在国家顶层设计方面,应重点着力于政绩评价体制以及社会保障体制方面改革。     

不同类型农户土壤保护认知及行为决策研究——以江汉平原368户农户调查为例

利用江汉平原农户调查数据,运用二元选择模型分析不同类型农户土壤保护认知与行为决策。结果表明:不同类型农户的土壤保护认知水平存在差异,且农户的土壤保护认知与其行为决策之间的差距较为明显;户主教育程度、农户土壤保护认知与耕地块数是影响所有类型农户土壤保护行为决策的显著因素;是否租入土地与接受农业技术培训对纯农户土壤保护行为有显著影响;人均耕地面积对I兼农户有显著影响;户主是否兼业与家庭非农就业比例对II兼农户有显著影响;户主年龄对III兼农户有显著影响。由此提出建议:提高各类农户土壤保护认知,缩小农户行为决策与认知差距的关键在于加强土壤保护知识与技术的宣传,培养农户土壤保护意识与技能,并通过土地整理等措施为农户采取土壤保护行为提供便利条件,在保障各方收入来源的基础上,引导土地从III兼农户向专业经营户流转。     

Methods for exploring treatment effect heterogeneity in subgroup analysis: an application to global clinical trials

Multi‐country randomised clinical trials (MRCTs) are common in the medical literature, and their interpretation has been the subject of extensive recent discussion. In many MRCTs, an evaluation of treatment effect homogeneity across countries or regions is conducted. Subgroup analysis principles require a significant test of interaction in order to claim heterogeneity of treatment effect across subgroups, such as countries in an MRCT. As clinical trials are typically underpowered for tests of interaction, overly optimistic expectations of treatment effect homogeneity can lead researchers, regulators and other stakeholders to over‐interpret apparent differences between subgroups even when heterogeneity tests are insignificant. In this paper, we consider some exploratory analysis tools to address this issue. We present three measures derived using the theory of order statistics, which can be used to understand the magnitude and the nature of the variation in treatment effects that can arise merely as an artefact of chance. These measures are not intended to replace a formal test of interaction but instead provide non‐inferential visual aids, which allow comparison of the observed and expected differences between regions or other subgroups and are a useful supplement to a formal test of interaction. We discuss how our methodology differs from recently published methods addressing the same issue. A case study of our approach is presented using data from the Study of Platelet Inhibition and Patient Outcomes (PLATO), which was a large cardiovascular MRCT that has been the subject of controversy in the literature. An R package is available that implements the proposed methods. Copyright © 2014 John Wiley & Sons, Ltd.     

Phase I trial design for drug combinations with Bayesian model averaging

Various statistical models have been proposed for two‐dimensional dose finding in drug‐combination trials. However, it is often a dilemma to decide which model to use when conducting a particular drug‐combination trial. We make a comprehensive comparison of four dose‐finding methods, and for fairness, we apply the same dose‐finding algorithm under the four model structures. Through extensive simulation studies, we compare the operating characteristics of these methods in various practical scenarios. The results show that different models may lead to different design properties and that no single model performs uniformly better in all scenarios. As a result, we propose using Bayesian model averaging to overcome the arbitrariness of the model specification and enhance the robustness of the design. We assign a discrete probability mass to each model as the prior model probability and then estimate the toxicity probabilities of combined doses in the Bayesian model averaging framework. During the trial, we adaptively allocated each new cohort of patients to the most appropriate dose combination by comparing the posterior estimates of the toxicity probabilities with the prespecified toxicity target. The simulation results demonstrate that the Bayesian model averaging approach is robust under various scenarios. Copyright © 2015 John Wiley & Sons, Ltd.     

Notes on estimation of the intraclass correlation under the AB/BA crossover trial

Under the AB/BA crossover trial, we focus our attention on estimation of the intraclass correlation in normal data. We develop both point and interval estimators in closed form for the intraclass correlation. We employ Monte Carlo simulation to study the performance of these estimators in a variety of situations. We note that the estimators developed here for the intraclass correlation remain valid even when there are possibly unexpected carry-over effects.     

State Council Issued Opinions on Further Promoting Reform of Household Registration System

正In order to fulfill the requirement of further promoting the reform of household registration system,accelerate orderly citizenization of permanent residents and give impetus to full coverage of urban basic public services for permanent residents,the State Council has issued the following opinions recently.Overall Requirements Guiding Ideology To meet the needs for advancing new urbanization,further promote the reform of household registration system and carry out the policies