Exploring Parameter Relations for Multi‐Stage Models in Stage‐Wise Constant and Time Dependent Hazard Rates

Single cohort stage‐frequency data are considered when assessing the stage reached by individuals through destructive sampling. For this type of data, when all hazard rates are assumed constant and equal, Laplace transform methods have been applied in the past to estimate the parameters in each stage‐duration distribution and the overall hazard rates. If hazard rates are not all equal, estimating stage‐duration parameters using Laplace transform methods becomes complex. In this paper, two new models are proposed to estimate stage‐dependent maturation parameters using Laplace transform methods where non‐trivial hazard rates apply. The first model encompasses hazard rates that are constant within each stage but vary between stages. The second model encompasses time‐dependent hazard rates within stages. Moreover, this paper introduces a method for estimating the hazard rate in each stage for the stage‐wise constant hazard rates model. This work presents methods that could be used in specific types of laboratory studies, but the main motivation is to explore the relationships between stage maturation parameters that, in future work, could be exploited in applying Bayesian approaches. The application of the methodology in each model is evaluated using simulated data in order to illustrate the structure of these models.     

A combinatorial study of two-periodic random walks

Two-periodic random walks have up-steps and down-steps of one unit as usual, but the probability of an up-step is α after an even number of steps and β = 1 ? α after an odd number of steps, and reversed for down-steps. This concept was studied by Böhm and Hornik^{[2 Böhm, W.; Hornik, K. On two-periodic random walks with boundaries. Stoch. Models 2010, 26, 165–194.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]]}. We complement this analysis by using methods from (analytic) combinatorics. By using two steps at once, we can reduce the analysis to the study of Motzkin paths, with up-steps, down-steps, and level-steps. Using a proper substitution, we get the generating functions of interest in an explicit and neat form. The parameters that are discussed here are the (one-sided) maximum (already studied by Böhm and Hornik^{[2 Böhm, W.; Hornik, K. On two-periodic random walks with boundaries. Stoch. Models 2010, 26, 165–194.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]]}) and the two-sided maximum. For the asymptotic evaluation of the average value of the two-sided maximum after n random steps, more sophisticated methods from complex analysis (Mellin transform, singularity analysis) are required. The approach to transfer the analysis to Motzkin paths is, of course, not restricted to the two parameters under consideration.     

笛卡儿"怀疑"的方法论研究

笛卡儿以理性为指导,以扬弃的方法和敢于怀疑一切的勇气寻求新知识的方法论原则,这种从"怀疑"开始的思维开辟了创新思维的先河,提出了研究事物的方法的重要性.在这个追求创新的时代,对我们现代人来说,转换思维方式以提高创新思维能力和勇气,进行理论和实践创新,在现实经济体制改革中选择适当的经济行为模式,正确认识处理社会出现的种种问题,具有一定的理论意义和现实意义.     

实现学生工作手段的现代化 提高德育工作的实效性

在贯彻落实党中央16号文件精神的过程中,首都师范大学运用各种管理系统,自主开发学生管理系统,加强网络建设,逐步实现工作的网络化.通过手段创新,提高了学生工作的效率,提高了德育工作的实效性和时效性.     

语文课堂教学中的创新教育

实行教学民主 ,优化创新环境应是语文课堂教学中实施创新教育的前提。因为创新活动是一种复杂的心理过程 ,它将会引起一系列的心理反应 ,同时也受其他心理因素的制约 ,所以实行教学民主 ,创设宽松的、自由的、民主的良好心理环境尤为必要。加强创新能力培养 ,强化创新训练 ,是语文课堂教学中实施创新教育的目的。创新能力就是在已有知识、经验的基础上 ,经过独立的分析、综合、联想、想像、比较、抽象和概括后所获得的能力。所以 ,创新能力的培养 ,还在于多方面开辟创新思维的活动空间 ,让学生在独立开启创造性思维中发展个性 ,促使创新意识的产生和能力的形成     

Quantile regression for large-scale data via sparse exponential transform method

In recent decades, quantile regression has received much more attention from academics and practitioners. However, most of existing computational algorithms are only effective for small or moderate size problems. They cannot solve quantile regression with large-scale data reliably and efficiently. To this end, we propose a new algorithm to implement quantile regression on large-scale data using the sparse exponential transform (SET) method. This algorithm mainly constructs a well-conditioned basis and a sampling matrix to reduce the number of observations. It then solves a quantile regression problem on this reduced matrix and obtains an approximate solution. Through simulation studies and empirical analysis of a 5% sample of the US 2000 Census data, we demonstrate efficiency of the SET-based algorithm. Numerical results indicate that our new algorithm is effective in terms of computation time and performs well for large-scale quantile regression.     

社会主义敬业精神的传统､本质和中国特色

劳动强度、劳动时间、劳动创造性是构成劳动的三个基本维度.但传统敬业精神往往以劳动强度和劳动时间作为主要评价标准,体现为“热爱、勤勉、克制”等工作作风.随着知识经济时代的到来,社会主义敬业精神也由传统的以道德定位向现代的价值定位方向转变,劳动的创造性或者创新性工作日益成为评价劳动者敬业精神的重要尺度,与此相对应,“创新”成为社会主义敬业精神的本质.中国特色的敬业精神是社会主义敬业精神民族化和时代化的反映,它以创新为核心,是“实干作风、奉献思想、追求卓越”三者高度的统一.     

论影响科技成果转化的非技术因素

科技已成为推进社会、经济发展的果转化中最为根本的影响因素.但随着经济、社会的发展,其他要素如风险投资、管理、知识产权、资金等对科技成果转化都会产生不同程度的影响.文章主要分析影响科技成果转化的非技术因素.     

创新文化与写作的变革

文化是社会现实存在的反映。创新文化,是与时俱进的、反映社会现实存在的、满足社会需求的文化。写作是生产文化产品的行为过程,其变革,是向着创新文化的发展方向而同步运行的变革。写作变革运行的轨迹,应随着社会需求而转动;运行围绕的圆心,是创新文化。     

高校软件人才培养的创新实验区建设

为了更好地培养软件人才,提高大学生的工程实践能力,从大学生创新实验区建设实践出发,在软件人才培养实验区的硬件建设、软件建设(案例库和实验相关软件)以及软件人才培养模式方面进行实践探索。同时,从理论上阐述了三者是个有机整体,只有衔接得好、建设得好才能培养出国际一流的软件人才。