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171.
考虑到我国未来年度的OD分布预测中的路网构成变化、区域经济布局变动、区域经济增长速度差异等一些具有时变性和特殊性因素,采用在“四阶段法”运量预测基础上改进而成的“三阶段法”进行高速铁路短期客运量预测。首先采用组合预测模型进行趋势运量预测,然后采用多元LOGIT模型进行方式分担,最后采用弹性系数诱增模型进行诱增运量预测。以京沪高铁为例,采用“三阶段法”预测了2014年和2015年京沪高铁本线及跨线单向客流量。  相似文献   
172.
We present influence diagnostics for linear measurement error models with stochastic linear restrictions using the corrected likelihood of Nakamura in 1990. The case deletion and mean shift outlier models are developed to identify outlying and influential observations. We derive a corrected score test statistic for outlier detection based on mean shift outlier models. The analogs of Cook's distance and likelihood distance are proposed to determine influential observations based on case deletion models. A parametric bootstrap procedure is used to obtain empirical distributions of the test statistics and a simulation study has been used to evaluate the performance of the proposed estimators based on the mean squares error criterion and the score test statistic. Finally, a numerical example is given to illustrate the theoretical results.  相似文献   
173.
The weighted kappa coefficient of a binary diagnostic test is a measure of the beyond-chance agreement between the diagnostic test and the gold standard, and is a measure that allows us to assess and compare the performance of binary diagnostic tests. In the presence of partial disease verification, the comparison of the weighted kappa coefficients of two or more binary diagnostic tests cannot be carried out ignoring the individuals with an unknown disease status, since the estimators obtained would be affected by verification bias. In this article, we propose a global hypothesis test based on the chi-square distribution to simultaneously compare the weighted kappa coefficients when in the presence of partial disease verification the missing data mechanism is ignorable. Simulation experiments have been carried out to study the type I error and the power of the global hypothesis test. The results have been applied to the diagnosis of coronary disease.  相似文献   
174.
The purpose was to assess RDS estimators in populations simulated with diverse connectivity characteristics, incorporating the putative influence of misreported degrees and transmission processes. Four populations were simulated using different random graph models. Each population was “infected” using four different transmission processes. From each combination of population x transmission, one thousand samples were obtained using a RDS-like sampling strategy. Three estimators were used to predict the population-level prevalence of the “infection”. Several types of misreported degrees were simulated. Also, samples were generated using the standard random sampling method and the respective prevalence estimates, using the classical frequentist estimator. Estimation biases in relation to population parameters were assessed, as well as the variance. Variability was associated with the connectivity characteristics of each simulated population. Clustered populations yield greater variability and no RDS-based strategy could address the estimation biases. Misreporting degrees had modest effects, especially when RDS estimators were used. The best results for RDS-based samples were observed when the “infection” was randomly attributed, without any relation with the underlying network structure.  相似文献   
175.
随着我国经济的转型发展创新教育在大学教育中的地位被凸显出来,技职类大学的创新教育是摆在我们面前的一个实际课题。我国台湾地区高校这类教育开始比大陆早一些,在政策的制定、教师的培养、课程的设计等方面有一些经验可以借鉴,能给我们一些重要的启示。  相似文献   
176.
中式艺术菜名在中式菜谱汉译英翻译中最难处理,最具争议。针对中式艺术菜名的翻译,依据运用修辞手法的不同把中式艺术菜名分为比喻型、吉祥语型、典故型、诗句型和夸张型等五大类型,并参照海外著名中餐厅与西餐厅菜谱,为不同类型艺术菜名探讨恰当有效的翻译策略与方法,旨在弘扬中国饮食文化。  相似文献   
177.
Mixed-Weibull distribution has been used to model a wide range of failure data sets, and in many practical situations the number of components in a mixture model is unknown. Thus, the parameter estimation of a mixed-Weibull distribution is considered and the important issue of how to determine the number of components is discussed. Two approaches are proposed to solve this problem. One is the method of moments and the other is a regularization type of fuzzy clustering algorithm. Finally, numerical examples and two real data sets are given to illustrate the features of the proposed approaches.  相似文献   
178.
The purpose of the study was to extend the literature on verbal self-regulation by using the “silent dog” method to evaluate the role of verbal regulation over nonverbal behavior in 2 individuals with autism. Participants were required to talk-aloud while performing functional computer tasks.Then the effects of distracters with increasing demands on target behavior were evaluated as well as whether self-talk emitted by Participant 1 could be used to alter Participant 2''s performance. Results suggest that participants'' tasks seemed to be under control of self-instructions, and the rules generated from Participants 1''s self-talk were effective in teaching computer skills to Participant 2. The silent dog method was useful in evaluating the possible role of self-generated rules in teaching computer skills to participants with autism.  相似文献   
179.
The object of an economic model for the quality selection problem is to select the best parameter value for an input quality characteristic (X) so that the quality loss incurred on an output quality characteristic (Y) is minimized. The relation function between Y and X is assumed to be known throughout the article. In the work of Taguchi's experimentations, the selection of best parameter values is solved by two-step optimization when Y is adjustable. In the article, it is further extended to the case where Y is non-adjustable. An economic quality selection model with a general relation function is proposed based on a Taylor-series method for both adjustable and non-adjustable cases. A special case of a quality selection model with a quadratic relation function is also studied. A circuit example provided by Taguchi is presented to illustrate the use of this model.  相似文献   
180.
《侵权责任法》第87条对侵权人不明的高楼落物侵权责任的承担进行了规定,具有保障受害人得到补偿、统一司法实践、降低致害概率的积极意义。但是,该规定也存在许多不足之处,主要表现为不利于社会和谐、容易引发道德风险、预防功能不充分、适用前提不明确等,没有很好地解决高楼落物侵权所面临的困境。采取社会救济、高楼落物赔偿基金、保险赔偿等多种途径相结合的救济方式,行政法、刑法与《侵权责任法》相配合的惩罚制度,不仅可以使受害人得到及时的、充分的补偿,而且可以有效预防此类侵权损害的发生。  相似文献   
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