A Note on the Use of Confidence Limits following Rejection of a Null Hypothesis

The equivalence of some tests of hypothesis and confidence limits is well known. When, however, the confidence limits are computed only after rejection of a null hypothesis, the usual unconditional confidence limits are no longer valid. This refers to a strict two-stage inference procedure: first test the hypothesis of interest and if the test results in a rejection decision, then proceed with estimating the relevant parameter. Under such a situation, confidence limits should be computed conditionally on the specified outcome of the test under which estimation proceeds. Conditional confidence sets will be longer than unconditional confidence sets and may even contain values of the parameter previously rejected by the test of hypothesis. Conditional confidence limits for the mean of a normal population with known variance are used to illustrate these results. In many applications, these results indicate that conditional estimation is probably not good practice.     

从刘勰的“梓材”说看理想人格的建构

刘勰在《文心雕龙·程器》篇中提出梓材之说,要求君子具备藏器待时的心理素养、内圣外王的道德建构、旷达超脱的人生态度和经国济世的智慧才能,集中体现了中国传统人格的理想范式,但也暴露出中国传统人格理念中重德性而轻知性、重理性而轻感性、重群体而轻个体的历史局限。     

期货市场涨跌停板幅度设置的模型研究

涨跌停板幅度规定了期货交易中每日价格波动的范围,是涨跌停板制度的核心,过高的停板幅度不利于抑制价格的剧烈波动,过低的停板幅度又会妨碍期货市场价格发现功能的实现。尽管涨跌停板制度已被期货交易所广泛采用,但对如何设置合理的涨跌停板幅度的研究尚不成熟,实用性较差。本文在国内外学者研究的基础上,基于自履行合约理论和极值理论构建期货涨跌停板幅度设置模型。模型通过合约自履行条件下涨跌停板幅度与保证金水平的关系,获得合理的涨跌停板幅度,并应用极值理论修正了以往模型中期货收益率的正态分布假设,提高了实用性。最后,本文应用该模型对我国铜和天然橡胶期货涨跌停板幅度进行了实际测算。     

The Influence of Term Limits on the Electoral Success of Women

ABSTRACT

In this paper I develop a theoretical approach that rehabilitates identity as a political and interpretive, not essentialist, category. To this end, I explore versions of feminist standpoint theory developed by Nancy Hartsock and Alison Jaggar. While these versions of standpoint theory have marked the significance of experience and knowledge for feminist practice, their conception of subjectivity is too unified and, therefore, creates problems for addressing the epistemological implications of “difference.” For this approach to feminist subjectivity, power relations of race, class, and nation are “differences” which are viewed as threatening endless fragmentation or promising plurality. Alternatively, following Norma Alarcon's theory of multiple-voiced subjectivity, I argue that relations of power produce complex subjectivities situated within multiple, intersecting axes of power: race, class, sex, gender, nation. These relations of power mark the terrain of experience as an interpretive field for the production of knowledge and collective identity. This approach shifts the interpretation of experience and knowledge from a paradigm of essentialism, fragmentation, and pluralist difference to a paradigm of accountability and coalition.     

Reaching Temporary Time Limits

Abstract

Concerns about long-term welfare dependency provided the primary reason for the nation's time-limited welfare benefits. This study compares the likelihood of reaching temporary time limits between families who repeatedly attempted to leave Temporary Assistance to Needy Families (TANF) and those who remained on the rolls continuously. Using logit analysis, we find that relatively few families reach the 24 month time limits in Nevada because most families left on their own for employment, marriage or for other reasons. This finding raises the question of whether time limits are even necessary. Government needs to further explore the service needs of families who are about to reach their time limits.     

List of tables

Abstract

This paper details a model of intermittent psychotherapy defined as a sequence of time-limited psychotherapies over an extended period of time. The model emphasizes the importance of relationship, careful assessment of short-and long-term client needs, focused work in successive stages, attention to termination while maintaining connection, and planned follow-up contact. To support the intermittent model, a new conceptualization of termination is offered, allowing for maintenance of client-clinician connection. Selection and exclusion criteria are discussed, as are necessary skills for the treating clinician. A case example illustrates application of the intermittent model. A careful review of the pertinent research literature on time-limited therapies is included.     

Effects of Customized Balance Exercises on Older Women Whose Balance Ability Has Deteriorated With Age

Falls represent a major public health problem for older adults, and loss of balance (LOS) abilities is one of the primary causes of falls. Previous studies have shown that balance training is effective in improving physical function and decreasing risk of falls. However, little attention has been given specifically to balance training in older adults with very poor balance. The purpose of this study was to determine the effect of a 12-week customized balance exercise program on LOS for community-dwelling older women with poor balance ability. Twenty-four older women with poor balance (composite maximum excursion [MXEcomp] score of less than 70% based on Limits of Stability) were divided into an exercise group and control group. After 12 weeks of balance exercises, mean MXEcomp improved (p < .05) from 58.6% to 79.0% in the exercise group. EPEcomp (composite endpoint excursion), RTcomp (composite reaction time), SVcomp3 (composite sway velocity on thick foam with the eyes open), UG (up and go) also improved, but the functional reach and other static balance indexes did not change. These results indicated that balance training allows older adults with poor balance to improve dynamic balance ability and potentially reduce risk for falls.     

Time's Up

SUMMARY

This study examines the intersection of two important welfare realities, the imposition of a lifetime limit on cash benefits and the concentration of cases in urban areas. Using survey data on a random sample of June 2002, single-parent TANF families in a large city (Baltimore), the characteristics and self-perceived barriers of long-term (60+ months) and short-term (< 12 months) recipients are compared. Although the demographics of the two groups are very similar, long-term cases were more likely to report barriers, such as having a family member with a health problem or living in bad neighborhood conditions, and to face more barriers than short-term cases. Policy and practice implications are identified.     

高校社科图书资料工作二、三题

本文就新形势下高校图书资料工作的范围扩展和延伸进行了论述 ,阐述了它在校园文化建设中的地位和作用 ,探讨了图书资料工作者为适应知识经济兴起和信息时代的要求 ,应具备的条件和努力的方向。     

Robust cusum: a robustness study for cusum quality control schemes

A standard CUSUM control scheme and four modified CUSUM control schemes are evaluated for robustness. The average run length (ARL) for each scheme is evaluated using a contaminated normal distribution, a distribution that has longer tails than the normal. A CUSUM control scheme that ignores the first suspected outlier, but gives an out-of-control signal for two successive outliers is found to perform well.