Semi-parametric hybrid empirical likelihood inference for two-sample comparison with censored data

Two-sample comparison problems are often encountered in practical projects and have widely been studied in literature. Owing to practical demands, the research for this topic under special settings such as a semiparametric framework have also attracted great attentions. Zhou and Liang (Biometrika 92:271–282, 2005) proposed an empirical likelihood-based semi-parametric inference for the comparison of treatment effects in a two-sample problem with censored data. However, their approach is actually a pseudo-empirical likelihood and the method may not be fully efficient. In this study, we develop a new empirical likelihood-based inference under more general framework by using the hazard formulation of censored data for two sample semi-parametric hybrid models. We demonstrate that our empirical likelihood statistic converges to a standard chi-squared distribution under the null hypothesis. We further illustrate the use of the proposed test by testing the ROC curve with censored data, among others. Numerical performance of the proposed method is also examined.     

试论参与型征地批准程序的建构

目前我国土地征收审批的审查主体、审查标准和内容等都存在严重的结构性缺陷。参与型征地批准程序是使被征地者参与征地审批,以弥补现行征地审批程序中"公共利益"界定模糊和权力监督乏力的缺陷。参与型征地批准程序必须在制度设计上重视主体参与的广度和深度,只有这样才能实现程序设计的目的。     

杜诗自注与诗歌境域的开拓

杜甫诗歌的自注作为中国诗歌自注体的早期代表,记录下了与诗歌创作相关的丰富信息,充分发挥了诗歌自注体的辅助功能,诗与注的紧密互动对杜甫诗歌的情志表现产生了一定的积极影响。杜甫再次介入诗歌进行自我诠释的动机反映了诗人对创作的自省心理,流露出其多方开拓新境的诗学追求。     

农户小麦补贴品种选择行为的影响因素分析

通过对皖北地区581个农户的实地调查,利用Logit模型对影响农户小麦补贴品种选择行为的因素进行了实证分析,结果表明:我国良种补贴政策实施效果还不够理想,仅有60.7%的农户采用政府推介品种;户主性别、文化程度、是否示范户、农户经营规模、是否与农技员有过联系、对补贴品种认知水平及态度是影响农户小麦补贴品种选择行为的重要因素。进一步优化良种补贴政策、推进基层农业技术推广体系改革、提高农户的教育水平、加大政策的宣传力度、加快土地流转是促进良种推广的有效途径。     

Lone mothers' time allocations: choices and satisfactions

This paper uses the 2006 Australian Time Use Survey to examine the allocation of time to personal care, employment‐related activities, home duties, leisure and child care of lone mothers, in comparison to the time allocations of single women, women in childless couples and partnered mothers. Both primary and secondary time allocations are considered. The satisfactions that women report concerning their current time allocations are also analysed. The time use and satisfaction data are described using both tabulations and multiple regression methods. Lone mothers are shown to have similar time allocations as the other types of households, even though they have different financial and time resources. This raises the concern that lone mothers' desire or need to maintain such time allocations may lead to task overload. Consistent with this, lone mothers are found to be less satisfied with the way they allocate their time than single women and partnered mothers. The tensions associated with time use among lone mothers discussed in the literature are real, and important.     

Work rehabilitation for migrant workers with work injury--the magic of Chinese paper cutting

As China has gradually transformed from agricultural economy into industrial economy since 1978, occupational injuries and diseases become a serious social problem in China. For occupational rehabilitation professionals, helping workers with occupational injuries and diseases, return to work and re-integrate to community are the ultimate goals of occupational rehabilitation. This article reports a new indigenous initiative with cultural notions in occupational rehabilitation piloted by Guangdong Provincial Rehabilitation Center. Case studies reflected that by learning and practicing traditional Chinese paper cutting, workers with occupational injury and disease could regain their self confidence, identity their strengths, learn more vocational skills as well as to re-integrate into community.     

A linear programming duality approach to analyzing strictly nonblocking <Emphasis Type="Italic">d</Emphasis>-ary multilog networks under general crosstalk constraints

When a switching network topology is used for constructing optical cross-connects, as in the circuit switching case, no two routes are allowed to share a link. However, if two routes share too many switching elements, then crosstalk introduced at those switching elements degrades signal quality. Vaez and Lea (IEEE Trans. Commun. 48:(2)316–323, 2000) introduced a parameter c which is the maximum number of distinct switching elements a route can share with other routes in the network. This is called the general crosstalk constraint. This paper presents a new method of analyzing strictly nonblocking multi-log networks under this general crosstalk constraint using linear programming duality.     

新疆维吾尔族桑皮纸的研究与应用

本文对新疆维吾尔族桑皮纸的历史、维吾尔族民间制作工艺和应用等情况进行了探索性研究。桑皮纸在新疆非常古老,历史很久远,而新疆的桑皮纸历代生产以和田地区为中心,古老的和田孕育了悠久的桑皮纸历史文化和民间制作工艺技术。桑皮纸最大特点是结实而有韧性、柔嫩、防虫、拉力强、不褪色、吸水力强,主要用于书画装裱、包扎纸币、制伞、包装、制鞭炮,此外,还被用在印钱、制扇、印刷书籍等文化工艺生产活动中。     

Joint chance-constrained staffing optimization in multi-skill call centers

This paper concerns the staffing optimization problem in multi-skill call centers. The objective is to find a minimal cost staffing solution while meeting a target level for the quality of service (QoS) to customers. We consider a staffing problem in which joint chance constraints are imposed on the QoS of the day. Our joint chance-constrained formulation is more rational capturing the correlation between different call types, as compared to separate chance-constrained versions considered in previous studies. We show that, in general, the probability functions in the joint-chance constraints display S-shaped curves, and the optimal solutions should belong to the concave regions of the curves. Thus, we propose an approach combining a heuristic phase to identify solutions lying in the concave part and a simulation-based cut generation phase to create outer-approximations of the probability functions. This allows us to find good staffing solutions satisfying the joint-chance constraints by simulation and linear programming. We test our formulation and algorithm using call center examples of up to 65 call types and 89 agent groups, which shows the benefits of our joint-chance constrained formulation and the advantage of our algorithm over standard ones.

     

A pragmatic adaptive enrichment design for selecting the right target population for cancer immunotherapies

One of the challenges in the design of confirmatory trials is to deal with uncertainties regarding the optimal target population for a novel drug. Adaptive enrichment designs (AED) which allow for a data-driven selection of one or more prespecified biomarker subpopulations at an interim analysis have been proposed in this setting but practical case studies of AEDs are still relatively rare. We present the design of an AED with a binary endpoint in the highly dynamic setting of cancer immunotherapy. The trial was initiated as a conventional trial in early triple-negative breast cancer but amended to an AED based on emerging data external to the trial suggesting that PD-L1 status could be a predictive biomarker. Operating characteristics are discussed including the concept of a minimal detectable difference, that is, the smallest observed treatment effect that would lead to a statistically significant result in at least one of the target populations at the interim or the final analysis, respectively, in the setting of AED.