A simple,doubly robust,efficient estimator for survival functions using pseudo observations

Survival functions are often estimated by nonparametric estimators such as the Kaplan‐Meier estimator. For valid estimation, proper adjustment for confounding factors is needed when treatment assignment may depend on confounding factors. Inverse probability weighting is a commonly used approach, especially when there is a large number of potential confounders to adjust for. Direct adjustment may also be used if the relationship between the time‐to‐event and all confounders can be modeled. However, either approach requires a correctly specified model for the relationship between confounders and treatment allocation or between confounders and the time‐to‐event. We propose a pseudo‐observation–based doubly robust estimator, which is valid when either the treatment allocation model or the time‐to‐event model is correctly specified and is generally more efficient than the inverse probability weighting approach. The approach can be easily implemented using standard software. A simulation study was conducted to evaluate this approach under a number of scenarios, and the results are presented and discussed. The results confirm robustness and efficiency of the proposed approach. A real data example is also provided for illustration.     

Empirical likelihood inference for a semiparametric hazards regression model

ABSTRACT

We investigated the empirical likelihood inference approach under a general class of semiparametric hazards regression models with survival data subject to right-censoring. An empirical likelihood ratio for the full 2p regression parameters involved in the model is obtained. We showed that it converged weakly to a random variable which could be written as a weighted sum of 2p independent chi-squared variables with one degree of freedom. Using this, we could construct a confidence region for parameters. We also suggested an adjusted version for the preceding statistic, whose limit followed a standard chi-squared distribution with 2p degrees of freedom.     

我国35个大中城市房价-持久收入比研究

房价收入比是反映居民购房可支付能力的重要指标。为了更真实准确反映我国居民长期承受的购房负担,本文基于持久收入假说,利用我国35个大中城市数据,建立状态空间模型,估计出持久收入意义下的房价收入比,通过情景分析确定其合理上限,并分析主要特征。研究表明：①我国房价-持久收入比的合理上限为7.6,2002-2013年35个大中城市的房价-持久收入比均值是9.2,其中28个城市已超过该上限,比值最高的北京已达到14.9;②城市越发达,则房价-持久收入比越高,居民需要承受的购房压力越大,且在时间趋势上,一线与二三线城市间的差距呈现扩大趋势;③在地理分布上,我国东部、中部、东北地区、西部大中城市的房价-持久收入比呈现从高到低的排列顺序;④相比于传统方法中根据可支配收入测算的房价收入比,房价-持久收入比与其约有10%的差异。当前我国政府应采取有效措施继续限制房价,减轻居民购房负担。     

A Smooth Bootstrap Procedure towards Deriving Confidence Intervals for the Relative Risk

Given a pair of sample estimators of two independent proportions, bootstrap methods are a common strategy towards deriving the associated confidence interval for the relative risk. We develop a new smooth bootstrap procedure, which generates pseudo-samples from a continuous quantile function. Under a variety of settings, our simulation studies show that our method possesses a better or equal performance in comparison with asymptotic theory based and existing bootstrap methods, particularly for heavily unbalanced data in terms of coverage probability and power. We illustrate our procedure as applied to several published data sets.     

人力资源强省评价指标构建——基于区域人力资源竞争力视角

基于区域人力资源竞争力视角,对人力资源强省各个构成因素进行综合考虑,应用分析法、频数统计法、德尔菲问卷法及层次分析法,构建出衡量人力资源强省的指标及其权重。为我国各省对于人力资源强省建设和优化提供一定的理论依据和借鉴。     

新时期大连城市发展的机遇与挑战

2007年．大连市实现地区生产总值3131亿元,按可比价格计算比上年增长17．5％．增幅达到1994年以来的最高值。人均生产总值（按常住平均人口计算）达到5．16万元,按年末汇率折算为7067美元。全市GDP超过3000亿元．人均GDP超过7000美元,大连在东北老工业基地振兴中的先导作用日益显现,产业结构不断优化和高级化,东北亚重要国际航运中心建设框架基本形成,大连市的经济社会发展步入一个崭新的历史时期。与此同时,大连城市经济发展所依托的区域经济环境发生了重大变化．东北老工业基地振兴步入了关键时期,辽宁沿海开发又使大连成为“五点一线”沿海经济带的先导,所有这一切都使大连城市发展面临新的机遇和挑战,这是大连在今后的城市发展战略中必须要认真分析的问题。     

上海在“一带一路”和长江经济带建设中的定位与作用研究

中国开展“一带一路”建设并非只是为了解决西部发展的权宜之计,而是继续支持西部大开发、东北地区等老工业基地全面振兴,推动京津冀协同发展和长江经济带发展,抓紧落实国家新型城镇化规划,举全国之力全面对外开放的长期战略.因此,上海亟须主动将本地区的未来发展与国家的发展战略有效衔接,通过参与“一带一路”和长江经济带建设找到上海的发展机会.     

美国对阿拉伯能源战略的演变及其启示

美国对阿拉伯能源战略一直是其对外能源战略的重中之重,从一战到伊战曾经历多次重大调整.中国在经济全球化形势下与阿拉伯国家开展能源合作时可借鉴这一能源战略,做到扬长避短,通过实行多元化的能源战略、建立战略石油储备体系、建立能源对话合作机制以及扩大阿拉伯产油国对中国贸易与投资的份额使中阿能源合作得以顺利进行,并得到进一步发展.     

中国国际进口博览会市场化运作设计及其保障机制

目前,进博会主要采用政府主导的包办模式,这对于确保运行稳定性和提升效率具有重要意义,但较高程度的行政化办会也面临一定的挑战.推动进博会向市场化运作的方向发展,有助于消除西方国家和企业的疑虑,充分调动国内外各方资源,也有利于实现展会的可持续运营,减轻财政压力.鉴于进博会重要的战略意义,同时兼顾市场化发展的重要导向,其运营方式可从政府包办向政府主办转变,重点加强进博会的市场价值挖掘,提升进博会的市场化运作水平.     

基于“重要性-影响力”框架的非首都功能疏解路径研究——以北京市动物园服装批发市场搬迁为例

利益相关者分析法是分析复杂管理问题的重要方法,广泛应用于企业管理、项目管理及公共政策领域。随着北京市非首都核心功能的疏解思路的提出,作为低端产业代表的动物园批发市场的外迁势在必行。运用重要性-影响力利益相关者分析框架,对动批搬迁政策中涉及的利益相关者进行界定,分别分析其利益诉求并进行合理划分,依据各利益相关者对政策的重要性程度和影响力大小以及各相关者之间的利益冲突分别制定解决对策,同时将各种外部阻力纳入考虑范围,为北京市动物园批发市场搬迁提出可行路径,以期为其他类似公共政策制定问题提供参考。