Missing at random (MAR) in nonparametric regression - A simulation experiment

The additive model is considered when some observations on x are missing at random but corresponding observations on y are available. Especially for this model, missing at random is an interesting case because the complete case analysis is expected to be no more suitable. A simulation experiment is reported and the different methods are compared based on their superiority with respect to the sample mean squared error. Some focus is also given on the sample variance and the estimated bias. In detail, the complete case analysis, a kind of stochastic mean imputation, a single imputation and the nearest neighbor imputation are discussed.     

关于"判决性实验"的历史述评

"判决性实验"既是现代科学方法论的一个重要问题,也与马克思主义认识论的实践标准问题密切相关.本文通过对"判决性实验"的历史考察,简略地介绍了它由科学信念嬗变为哲学问题的基本过程,尤其对"知识整体论"者和"历史主义"学派的质疑作了一定的阐述,最后从实践标准的二重性角度对"判决性实验"进行了简要的评析.     

开放性实验教学的探索

开放性实验教学能激发学生学习的主动性,促进学生的创新素质和全面素质的提高,符合培养21世纪"具备坚实的基础理论、出色的科学实验能力和勇于开拓的创新精神的高素质人才"的要求.     

Tactical coordination in a multi-location and multi-stage operations structure: A model and a pharmaceutical company case

In this paper, we look at the internal supply chain of an internationally operating firm characterized by a multi-location and multi-stage operations structure. We address problems at three levels, namely the strategic, tactical, and operational levels. Our approach goes beyond the operational literature, and focuses primarily on the tactical level. We specify a model and a case that capture strategic and tactical issues and relate the tactical issues to organizational issues. We simulate coordination in different organizational forms pertaining to the ‘tactical control’ of the firm. Our analysis suggests that a functionally organized multi-location and multi-stage operations structure using traditional planning will not work. The choice is between a strongly IT-based, centralized organization or a more decentralized organization using transfer prices as the coordination device.     

提高学生动物生理学实验的积极性和主动性探讨

通过改变动物生理学传统实验方法的探索实践,让学生自己准备实验、采用先进的教学手段、规范实验报告、加强实验考核的科学性,多方面激发学生的学习兴趣,提高学生参与实验的积极性和主动性,效果明显。     

动静叶相互干涉的三维非定常流场数值模拟

将双时间步法应用于叶栅级的全三维黏性非定常数值求解，讨论了分区算法中内边界条件的给定问题，本算法可保证分区边界上具有与内点相同的精度，具有很好的数值稳定性，且通量基本守恒，将该方法应用于具有弯曲导叶的涡轮级的计算可得到典型的非定常流谱，揭示了动静叶之间的相互干涉对叶片气动性能的影响，数值计算结果表明本文给出的算法是合理有效的。     

Detection of interactions in experiments on large numbers of factors

One of the main advantages of factorial experiments is the information that they can offer on interactions. When there are many factors to be studied, some or all of this information is often sacrificed to keep the size of an experiment economically feasible. Two strategies for group screening are presented for a large number of factors, over two stages of experimentation, with particular emphasis on the detection of interactions. One approach estimates only main effects at the first stage (classical group screening), whereas the other new method (interaction group screening) estimates both main effects and key two-factor interactions at the first stage. Three criteria are used to guide the choice of screening technique, and also the size of the groups of factors for study in the first-stage experiment. The criteria seek to minimize the expected total number of observations in the experiment, the probability that the size of the experiment exceeds a prespecified target and the proportion of active individual factorial effects which are not detected. To implement these criteria, results are derived on the relationship between the grouped and individual factorial effects, and the probability distributions of the numbers of grouped factors whose main effects or interactions are declared active at the first stage. Examples are used to illustrate the methodology, and some issues and open questions for the practical implementation of the results are discussed.     

Smallholder Preferences for Agri‐environmental Change at the Bhoj Wetland,India

Incentive‐based approaches have gained policy interest in linking change in agricultural land management with environmental conservation. This article investigates how scheme design influences smallholder farmers' decisions to switch to organic farming to reduce water pollution, drawing on a study at a Ramsar wetland site providing water for the city of Bhopal. Results from a choice experiment suggest that transitional payments are necessary to overcome farmer constraints to adopt organic farming, and that effective land certification has the potential to act as a self‐enforcing mechanism linking farmer incomes with wetland conservation benefits.     

英语RC挂靠偏向的眼动实验研究

RC挂靠现象研究对揭示歧义句加工内部心理过程具有重要意义,现有的修饰语挂靠若干假说是否适用中国英语学习者值得深入探索。本研究通过Tobii T-120型眼动仪,随机抽取49名英语专业本科生进行歧义句加工眼动实验。研究显示,RC关系从句呈现NP1挂靠偏向,支持语言调整假说。     

电子信息工程专业综合实验初探

提出了一个建设电子信息综合实验室 ,并开设电子信息综合实验的设想。该设想的实现 ,不仅可以充分利用实验室的现有设备 ,而且能将多门专业基础课和专业实验课有机的结合起来 ,进一步改善电子信息工程专业实验的效果