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91.
92.
We propose a Bayesian computation and inference method for the Pearson-type chi-squared goodness-of-fit test with right-censored survival data. Our test statistic is derived from the classical Pearson chi-squared test using the differences between the observed and expected counts in the partitioned bins. In the Bayesian paradigm, we generate posterior samples of the model parameter using the Markov chain Monte Carlo procedure. By replacing the maximum likelihood estimator in the quadratic form with a random observation from the posterior distribution of the model parameter, we can easily construct a chi-squared test statistic. The degrees of freedom of the test equal the number of bins and thus is independent of the dimensionality of the underlying parameter vector. The test statistic recovers the conventional Pearson-type chi-squared structure. Moreover, the proposed algorithm circumvents the burden of evaluating the Fisher information matrix, its inverse and the rank of the variance–covariance matrix. We examine the proposed model diagnostic method using simulation studies and illustrate it with a real data set from a prostate cancer study.  相似文献   
93.
Compared with most of the existing phase I designs, the recently proposed calibration-free odds (CFO) design has been demonstrated to be robust, model-free, and easy to use in practice. However, the original CFO design cannot handle late-onset toxicities, which have been commonly encountered in phase I oncology dose-finding trials with targeted agents or immunotherapies. To account for late-onset outcomes, we extend the CFO design to its time-to-event (TITE) version, which inherits the calibration-free and model-free properties. One salient feature of CFO-type designs is to adopt game theory by competing three doses at a time, including the current dose and the two neighboring doses, while interval-based designs only use the data at the current dose and is thus less efficient. We conduct comprehensive numerical studies for the TITE-CFO design under both fixed and randomly generated scenarios. TITE-CFO shows robust and efficient performances compared with interval-based and model-based counterparts. As a conclusion, the TITE-CFO design provides robust, efficient, and easy-to-use alternatives for phase I trials when the toxicity outcome is late-onset.  相似文献   
94.
方印 《学术交流》2012,(4):61-65
生态文明时代要求法律制度进行不同程度的生态化.在各种法律制度生态化历程中,民法制度的生态化起着相当重要的作用.民法基本制度的生态化是民法生态化的重要内容,它包括人格权制度的生态化、物权制度的生态化、合同制度的生态化、侵权责任制度的生态化.这其中,环境人格权是人格权制度生态化的主要内容;生态性用益物权是物权制度生态化的重要组成部分;环境物权交易合同是合同制度生态化的主要方面.以损害风险预防、现实损害救济赔偿、恢复责任承担为切入点,采用无过错责任与过错加重责任并用的原则,贯彻环境损害全程监管与责任追究的理念,对环境污染与生态破坏的源头与过程实行全面的控制与追责是侵权责任制度生态化的基本要素.  相似文献   
95.
依据对长江三角洲次级和县级区域资源配置现状的实证研究发现:一是长江三角洲区域在经历高速重化工业化的同时,开始跨入了内生增长模式的门槛,人力资本的贡献日益显现;二是越来越多的次级区域工业生产能力和技术创新能力正在超越北京、上海以及省会城市,由此国家的科技资源和高等教育资源也应当流向这些区域,使产业、科技、教育资源能够融合在同一个空间,以大大提高整个国家技术创新投入的收益;三是转变经济发展方式和实施创新型国家建设战略的真正落脚点是支持和推动更多的次级和县级区域建立高等教育体系,创造更多的人力资本,开展更多的技术创新活动,使更多的区域采取基于技术进步的增长战略。充足的证据表明,现在到了需要采取一个重视创新资源效率的区域增长战略的时候了。  相似文献   
96.
Sexual health education for young people is crucial not only for development of norms but also for protection against vulnerabilities during this stage in life. Although several systematic reviews have examined the effectiveness of peer-led sex education, none have focused on the extent of peer participation. The purpose of this review was to evaluate peer-led sexual health education interventions in more developed countries (MDCs). Electronic and manual searches across five social science, education, and medical databases were conducted. Fifteen articles were selected in total. Most (10 of 15) studies gave low or no responsibility to peers. The majority of articles found improvements in sexual health knowledge (13 of 14) and attitudes (11 of 15) at postintervention stages. Two studies showed improved self-efficacy, and three showed behavioral changes. A preliminary synthesis of effectiveness and level of participation was done. Meta-analysis revealed a large effect on knowledge change (Hedges’ g = 0.84, 95% confidence interval [CI]: 0.43 to 1.25) and a medium effect on attitude change (Hedges’ g = 0.49, 95% CI: 0.19 to 0.80). Peer-led interventions could be a powerful tool. This review shows that this approach is effective in changing knowledge and attitudes but not behaviors. Further research and action are needed to understand optimal implementation.  相似文献   
97.
师德评价对教师职业道德建设的影响   总被引:6,自引:0,他引:6  
张英涛 《学术交流》2001,(3):131-133
师德评价是教师以道德他律铸造自身道德素质的重要方式.这种评价,可以激发教师的职业责任感和道德荣誉感,唤起教师将师德原则和实践统一起来.在实践中,要构建一种教师和社会广泛参与的师德评价机制,从而加强我国教师职业道德建设.  相似文献   
98.
In survival analysis, it is routine to test equality of two survival curves, which is often conducted by using the log-rank test. Although it is optimal under the proportional hazards assumption, the log-rank test is known to have little power when the survival or hazard functions cross. To test the overall homogeneity of hazard rate functions, we propose a group of partitioned log-rank tests. By partitioning the time axis and taking the supremum of the sum of two partitioned log-rank statistics over different partitioning points, the proposed test gains enormous power for cases with crossing hazards. On the other hand, when the hazards are indeed proportional, our test still maintains high power close to that of the optimal log-rank test. Extensive simulation studies are conducted to compare the proposed test with existing methods, and three real data examples are used to illustrate the commonality of crossing hazards and the advantages of the partitioned log-rank tests.  相似文献   
99.
The main purpose of dose‐escalation trials is to identify the dose(s) that is/are safe and efficacious for further investigations in later studies. In this paper, we introduce dose‐escalation designs that incorporate both the dose‐limiting events and dose‐limiting toxicities (DLTs) and indicative responses of efficacy into the procedure. A flexible nonparametric model is used for modelling the continuous efficacy responses while a logistic model is used for the binary DLTs. Escalation decisions are based on the combination of the probabilities of DLTs and expected efficacy through a gain function. On the basis of this setup, we then introduce 2 types of Bayesian adaptive dose‐escalation strategies. The first type of procedures, called “single objective,” aims to identify and recommend a single dose, either the maximum tolerated dose, the highest dose that is considered as safe, or the optimal dose, a safe dose that gives optimum benefit risk. The second type, called “dual objective,” aims to jointly estimate both the maximum tolerated dose and the optimal dose accurately. The recommended doses obtained under these dose‐escalation procedures provide information about the safety and efficacy profile of the novel drug to facilitate later studies. We evaluate different strategies via simulations based on an example constructed from a real trial on patients with type 2 diabetes, and the use of stopping rules is assessed. We find that the nonparametric model estimates the efficacy responses well for different underlying true shapes. The dual‐objective designs give better results in terms of identifying the 2 real target doses compared to the single‐objective designs.  相似文献   
100.
会展产业作为“朝阳产业”,近年来在中国发展迅猛,刺激了会展人才需求,每年需新增从业人员20多万。但现有会展人才缺乏,高级会展人才尤缺,不能满足发展需求。广西借助每年举办中国—东盟博览会、中国—东盟商务与投资峰会和南宁国际民歌艺术节,大力发展”中国—东盟”会展产业,急需一批高素质、具有东盟文化特色的高级会展人才。针对于此,应加强会展产业的研究生培养,通过高校联合办学、加强学科建设,与会展管理部门、行业协会、企业等机构的合作等途径来共同培养。  相似文献   
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