Characterizing optimality among three-decision procedures for directional conclusions

Jones and Tukey (2000) proposed three-decision procedures for directional conclusions in statistical inference, considered as an alternative to the conventional usage of one- and two-tailed significance testing. Moreover, implicit in their suggestions was to consider a procedure to be optimal in case indefinite results were minimized among all procedures with a given control of error. First, we argue by example that this characterization of optimality is not very fruitful when formalized into the strong sense of uniform minimization. Next, imposing a further regularity condition on the comparative class of procedures, we relate the suggested characterization to optimality criteria from test theory (UMP unbiasedness). Similarly, we also consider characterizing optimality in terms of maximizing correct decision rates and minimizing incorrect decision rates. Finally, we demonstrate the applicability of the three considered characterizations with respect to exponential families of distributions.     

国有商业银行市场约束机制构建

从市场约束的概念出发论述了市场约束的运行机理。指出建立有效市场约束机制对促使国有商业银行谨慎经营决策、注重风险的防范及化解、保持金融秩序稳定具有重要的意义。结合市场约束的运行机理论述了目前对国有商业银行实施市场约束的必要性和存在的困难,提出构建国有商业银行市场约束机制,应树立激励相容的银行监管理念、促使国有商业银行成为市场化的主体,建立有效的公司治理结构、规范信息披露制度、建立有限的安全网、创造良好的运作环境。     

The uniformly most powerful unbiased tests involving the f-distribution

The uniformly most powerful unbiased test in exponential family situations involving the F-distrlbution is illustrated with examples. Its performance is compared with that of the more conventional equal-tails test. A FORTRAN program for computing the critical values and tail sizes of this test is also presented.     

商业银行法律风险研究

商业银行从创建之始就与法律风险相生相伴.在法律风险中求生存谋发展.全球金融格局与法制监管环境的复杂化,使得法律风险由地区性和局部性风险上升为全球性和综合性风险,对商业银行风险总量的影响越来越大.因此,对法律风险进行持续有效的防控成为国际大银行风险管理的核心内容.     

Default Estimation and Expert Information

Default is a rare event, even in segments in the midrange of a bank’s portfolio. Inference about default rates is essential for risk management and for compliance with the requirements of Basel II. Most commercial loans are in the middle-risk categories and are to unrated companies. Expert information is crucial in inference about defaults. A Bayesian approach is proposed and illustrated using a prior distribution assessed from an industry expert. The binomial model, most common in applications, is extended to allow correlated defaults. A check of robustness is illustrated with an ε-mixture of priors.     

Horizontal synthetic estimation: a strategy for estimating small area health related characteristics

It would be difficult to overestimate the general importance of relevant, detailed and timely small area data for health planning and research. However, the requisites of relevance, detail and timeliness are difficult — in some cases impossible — to satisfy. In the following discussion we sketch an approach for providing small area data useful for health planners. At this time our major concern is a comprehensive approach to estimates for small areas. The particular models and estimation procedures which we will present are adopted primarily for their heuristic value. They provide a convenient and not overly complex means of discussing important aspects of a comprehensive approach to small area estimation. Our objective is to delineate in a constructive fashion the broad parameters of a comprehensive approach to the estimation of health related small area data.     

An adaptive seamless phase II/III design for oncology trials with subpopulation selection using correlated survival endpoints

Although the statistical methods enabling efficient adaptive seamless designs are increasingly well established, it is important to continue to use the endpoints and specifications that best suit the therapy area and stage of development concerned when conducting such a trial. Approaches exist that allow adaptive designs to continue seamlessly either in a subpopulation of patients or in the whole population on the basis of data obtained from the first stage of a phase II/III design: our proposed design adds extra flexibility by also allowing the trial to continue in all patients but with both the subgroup and the full population as co-primary populations. Further, methodology is presented which controls the Type-I error rate at less than 2.5% when the phase II and III endpoints are different but correlated time-to-event endpoints. The operating characteristics of the design are described along with a discussion of the practical aspects in an oncology setting.     

Correlated defaults,temporal correlation,expert information and predictability of default rates

ABSTRACT

Dependence among defaults both across assets and over time is an important characteristic of financial risk. A Bayesian approach to default rate estimation is proposed and illustrated using prior distributions assessed from an experienced industry expert. Two extensions of the binomial model are proposed. The first allows correlated defaults yet remains consistent with Basel II’s asymptotic single-factor model. The second adds temporal correlation in default rates through autocorrelation in the systemic factor. Implications for the predictability of default rates are considered. The single-factor model generates more forecast uncertainty than does the parameter uncertainty. A robustness exercise illustrates that the correlation indicated by the data is much smaller than that specified in the Basel II regulations.     

论《巴塞尔新资本协议》中的法律风险

《巴塞尔新资本协议》首次将法律风险纳入了银行资本监管框架,对商业银行全面风险管理体系的建立以及各国银行资本监管制度的完善都提出了更高的要求。我国应当积极借鉴《新资本协议》体现的成熟的风险管理经验和先进的监管理念,通过制定监管指南的方式,从明确法律风险的表现形式、引导商业银行完善管理法律风险的组织结构以及推动商业银行开发管理法律风险的技术和方法等方面入手,逐步建立起法律风险监管制度。     

新巴塞尔协议信用风险度量模型的实证模拟——标准法、初级内部评级法和高级内部评级法的比较

新巴塞尔协议与旧巴塞尔协议相比,具有更多的灵活性,主要体现为在风险度量模型方面为银行提供了多种选择。巴塞尔协议的核心支柱是资本充足率要求,而风险度量模型正是计算资本充足率的基础。本文对商业银行的资产组合与风险参数进行了实证模拟,对信用风险度量的标准法、初级内部评级法与高级内部评级法进行了比较研究。研究表明：三种度量模型计算的加权风险资产,在数值上存在显著性差异,越高级别的模型所测度的加权风险资产数值越低;在商业银行的资产组合中,个人住房抵押贷款、中央政府债权、企业和个人贷款占总资产的比例对模型结果的差异性存在显著性的影响;资产组合风险水平越低,越高级的测度模型所计算的加权风险资产数值越低。