Inferences on the Means of Two Log-Normal Distributions: A Computational Approach Test

In this article, we propose a novel approach for testing the equality of two log-normal populations using a computational approach test (CAT) that does not require explicit knowledge of the sampling distribution of the test statistic. Simulation studies demonstrate that the proposed approach can perform hypothesis testing with satisfying actual size even at small sample sizes. Overall, it is superior to other existing methods. Also, a CAT is proposed for testing about reliability of two log-normal populations when the means are the same. Simulations show that the actual size of this new approach is close to nominal level and better than the score test. At the end, the proposed methods are illustrated using two examples.     

Statistical testing strategies for assessing treatment efficacy and marker accuracy in phase III trials

When a candidate predictive marker is available, but evidence on its predictive ability is not sufficiently reliable, all‐comers trials with marker stratification are frequently conducted. We propose a framework for planning and evaluating prospective testing strategies in confirmatory, phase III marker‐stratified clinical trials based on a natural assumption on heterogeneity of treatment effects across marker‐defined subpopulations, where weak rather than strong control is permitted for multiple population tests. For phase III marker‐stratified trials, it is expected that treatment efficacy is established in a particular patient population, possibly in a marker‐defined subpopulation, and that the marker accuracy is assessed when the marker is used to restrict the indication or labelling of the treatment to a marker‐based subpopulation, ie, assessment of the clinical validity of the marker. In this paper, we develop statistical testing strategies based on criteria that are explicitly designated to the marker assessment, including those examining treatment effects in marker‐negative patients. As existing and developed statistical testing strategies can assert treatment efficacy for either the overall patient population or the marker‐positive subpopulation, we also develop criteria for evaluating the operating characteristics of the statistical testing strategies based on the probabilities of asserting treatment efficacy across marker subpopulations. Numerical evaluations to compare the statistical testing strategies based on the developed criteria are provided.     

Blinded continuous monitoring in clinical trials with recurrent event endpoints

In studies with recurrent event endpoints, misspecified assumptions of event rates or dispersion can lead to underpowered trials or overexposure of patients. Specification of overdispersion is often a particular problem as it is usually not reported in clinical trial publications. Changing event rates over the years have been described for some diseases, adding to the uncertainty in planning. To mitigate the risks of inadequate sample sizes, internal pilot study designs have been proposed with a preference for blinded sample size reestimation procedures, as they generally do not affect the type I error rate and maintain trial integrity. Blinded sample size reestimation procedures are available for trials with recurrent events as endpoints. However, the variance in the reestimated sample size can be considerable in particular with early sample size reviews. Motivated by a randomized controlled trial in paediatric multiple sclerosis, a rare neurological condition in children, we apply the concept of blinded continuous monitoring of information, which is known to reduce the variance in the resulting sample size. Assuming negative binomial distributions for the counts of recurrent relapses, we derive information criteria and propose blinded continuous monitoring procedures. The operating characteristics of these are assessed in Monte Carlo trial simulations demonstrating favourable properties with regard to type I error rate, power, and stopping time, ie, sample size.     

Modifications of sequential designs in bioequivalence trials

Bioequivalence (BE) studies are designed to show that two formulations of one drug are equivalent and they play an important role in drug development. When in a design stage, it is possible that there is a high degree of uncertainty on variability of the formulations and the actual performance of the test versus reference formulation. Therefore, an interim look may be desirable to stop the study if there is no chance of claiming BE at the end (futility), or claim BE if evidence is sufficient (efficacy), or adjust the sample size. Sequential design approaches specially for BE studies have been proposed previously in publications. We applied modification to the existing methods focusing on simplified multiplicity adjustment and futility stopping. We name our method modified sequential design for BE studies (MSDBE). Simulation results demonstrate comparable performance between MSDBE and the original published methods while MSDBE offers more transparency and better applicability. The R package MSDBE is available at https://sites.google.com/site/modsdbe/ . Copyright © 2015 John Wiley & Sons, Ltd.     

商业银行董事会治理的独立有效性研究

根据经济合作与发展组织、巴塞尔银行监管委员会和中国银行业监督管理委员会等组织关于公司治理的相关原则、指引和法律规定,对商业银行董事会的独立有效性进行了综合分析,得出商业银行董事会的独立有效性主要体现在独立董事的独立性,职能委员会的独立性以及独立董事占董事会成员的比例3个方面以及规范的独立董事、职能委员会的产生机制和明确的独立董事、职能委员会的责权利制度是确保商业银行董事会独立有效性基础的结论,并提出中国商业银行董事会的适度规模为11人,其中独立董事占董事会成员的合适比例为50％以上的建议。     

档案信息利用服务网络化现状的思考

在社会信息化的趋势下,档案信息化已被高度关注。档案信息利用服务网络化是新形势下档案利用的一种新方式。由于诸多因素的制约,使得基于Internet平台的B S模式的网络利用服务明显滞后。本文从档案信息利用服务网络化的现状、产生的原因及对策三个方面做出分析。     

“银行”定义之比较研究与借鉴

认为定义银行的方法有两种 :形式认定主义与实质认定主义 ,而实质认定主义又有列举和概括式两种具体作法。英国采用实质认定主义 ;美国和香港以形式认定主义为基础 ,兼采实质认定主义 ;台湾采用形式认定主义。分析了我国《商业银行法》的定义并建议在坚持形式认定主义的同时 ,修正该法第 87条 ,对一些关键性的概念如存款、贷款加以明确界定     

整合营销传播策略在银行宣传营销中的运用

在阐述整合营销传播理论定义及要点的基础上,以招商银行的营销策略为主要例子,引用本土银行现有营销策略,论证了整合营销理论是我国银行新一轮竞争中的重要策略。     

商业银行非财务信用风险分析

传统的信用风险评估方法仅仅从贷款企业角度来评价商业银行所面临的信用风险,而且评价企业信用风险时,也集中在贷款企业的财务风险评价上,忽略了银行本身存、贷款结构和风险状况对信用风险的影响,造成了评估主体缺位。作为对众多文献的补充,从贷款企业非财务风险因素、银行风险因素和宏观经济环境风险因素三个方面进行了信用风险因素分析,完善了商业银行信用风险评估指标体系。     

中国商业银行市场结构与市场绩效分析

目前,中国商业银行寡头垄断的市场结构仍十分明显。国有商业银行虽然维系了资产规模的垄断结构,却没能取得维系垄断结构所应获取的垄断优势效应。造成这种状况的主要原因在于中国商业银行的垄断格局并非是在市场竞争的结果,而主要是由历史因素、行政手段所导致的。商业银行的市场结构再造,必须在借助政府力量重组现有商业银行结构体系的同时,降低行业进入壁垒,导入有效竞争。