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961.
杨忠 《陕西学前师范学院学报》2016,32(11):53-57
高校教师应该根据学生的认知能力、专业特征、社会经历和写作困惑等自身情况,指导学生撰写高等师范专科学校学生毕业论文。高校教师在了解和分析学生毕业论文撰写现状的基础上,除了要指导学生合理选题以外,还要指导学生善于积累,立足平时;深入学习,立足思考;素材整合,立足有效;反复提炼,立足创新。这样的毕业论文,才能够立足学生自身的认知能力,立足师范特色,立足在此过程中的自我发展。同时,这样的毕业论文指导,对于其他高校学生的毕业论文也同样具有指导意义。 相似文献
962.
C. Tenreiro 《统计学通讯:理论与方法》2017,46(7):3438-3458
Since the late 1980s, several methods have been considered in the literature to reduce the sample variability of the least-squares cross-validation bandwidth selector for kernel density estimation. In this article, a weighted version of this classical method is proposed and its asymptotic and finite-sample behavior is studied. The simulation results attest that the weighted cross-validation bandwidth performs quite well, presenting a better finite-sample performance than the standard cross-validation method for “easy-to-estimate” densities, and retaining the good finite-sample performance of the standard cross-validation method for “hard-to-estimate” ones. 相似文献
963.
In this article, we consider the variable selection and estimation for high-dimensional generalized linear models when the number of parameters diverges with the sample size. We propose a penalized quasi-likelihood function with the bridge penalty. The consistency and the Oracle property of the quasi-likelihood bridge estimators are obtained. Some simulations and a real data analysis are given to illustrate the performance of the proposed method. 相似文献
964.
Bertil Wegmann 《Journal of applied statistics》2015,42(2):380-397
Private and common values (CVs) are the two main competing valuation models in auction theory and empirical work. In the framework of second-price auctions, we compare the empirical performance of the independent private value (IPV) model to the CV model on a number of different dimensions, both on real data from eBay coin auctions and on simulated data. Both models fit the eBay data well with a slight edge for the CV model. However, the differences between the fit of the models seem to depend to some extent on the complexity of the models. According to log predictive score the IPV model predicts auction prices slightly better in most auctions, while the more robust CV model is much better at predicting auction prices in more unusual auctions. In terms of posterior odds, the CV model is clearly more supported by the eBay data. 相似文献
965.
This paper examines the effects of pre-ordering and pre-ordering with behavioral nudges on the selection of fruits, vegetables, and low-fat milk by National School Lunch Program (NSLP) participants in a Florida school. After collecting two weeks of baseline data, students in grades four and five were randomly assigned to one of two treatment groups: the first treatment group pre-ordered their lunches online using a unique software program; the second treatment group received behavioral nudges based on United States Department of Agriculture (USDA) MyPlate recommendations while pre-ordering. Student in grades four and seven served as the control group and continued to obtain their lunches through the normal lunch line. Using difference-in-difference regression analysis, we find that students in the first treatment group selected significantly more fruits, vegetables, and low-fat milk during the pre-ordering intervention phase of the study relative to students in the control group, 27.7%, 15.8%, and 16.3%, respectively, while students in the second treatment group selected significantly more fruits (51.4%), vegetables (29.7%) and low-fat milk (37.3%) than students in the control group. In addition, we find the nudge had a statistically significant positive effect in addition to the effect of pre-ordering; students who received the MyPlate nudge while pre-ordering selected statistically significantly more fruits, vegetables, and low-fat milk than students who pre-ordered without nudging. 相似文献
966.
Population pharmacokinetics (POPPK) has many important uses at various stages of drug development and approval. At the phase III stage, one of the major uses of POPPK is to identify covariate influences on human pharmacokinetics, which is important for potential dose adjustment and drug labeling. One common analysis approach is nonlinear mixed‐effect modeling, which typically involves time‐consuming extensive search for best fits among a large number of possible models. We propose that the analysis goal can be better achieved with a more standard confirmatory statistical analysis approach, which uses a prespecified primary analysis and additional sensitivity analyses. We illustrate this approach using a phase III study data set and compare the result with that calculated using the common exploratory approach. We argue that the confirmatory approach not only substantially reduces analysis time but also yields more accurate and interpretable results. Some aspects of this confirmatory approach may also be extended to data analysis in earlier stages of clinical drug development, i.e. phase II and phase I. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
967.
消费者的品牌形象认知对其品牌选择行为有重要影响。在消费者的品牌形象认知指标中,从对其品牌选择影响性质的差异来看,存在"维护因子"与"增长因子"两类指标。"维护因子"是品牌选择行为,也是品牌价值产生的必要条件;"增长因子"是品牌价值产生的充分条件,但必须在"维护因子"的基础上起作用。通过对不同品牌形象认知指标与消费者品牌选择行为之间的关系分析,有助于品牌管理者合理分配资源,提高品牌管理效率。 相似文献
968.
《Omega》2015
The smart phone industry has unique supply chain relationships. Companies at all levels of the supply chain compete and coordinate with each other for market share and profit. This paper examines the impact of power structures on the decision of pricing and channel selection between a free channel and a bundled channel. We investigate the smart phone supply chain that consists of a handset manufacturer and a telecom service operator. Based on game theory models, the manufacturer׳s optimal retail pricing policies in free and bundled channels and the telecom service operator׳s optimal subsidy policies in a bundled channel are derived under different power structures. It is demonstrated that the firm that has higher channel power will gain more profit, and the smart phone supply chain׳s profit in a Vertical Nash (VN) power structure is higher than that in Telecom Service Operator-Stackelberg (TS) and Manufacturer-Stackelberg (MS) power structures. It is also shown that the smart phone supply chain will choose a bundled channel in TS and MS power structures under certain conditions and will select a free channel in a VN power structure. 相似文献
969.
研究多元市场间的相关性对构建市场投资组合进而有效规避风险具有重要现实意义。将股票、基金、国债、期货、货币、外汇和现货市场纳入统一框架,以2010年10月1日至2014年3月31日的HS300指数、上证基金指数、国债指数、燃油期货指数、Shibor隔夜拆借利率、欧元兑人民币中间价和原油商品指数为样本,在结合GJR和EVT对各自边缘分布进行估计的基础上,运用R-Vine copula、D-Vine copula和C-Vine copula 3种模型综合探讨中国不同金融市场之间的净相关关系,并详细分析所有两两市场间的非条件相关性及其在一个市场条件下的条件相关性。实证结果表明,中国金融市场间表现出厚尾相关性和非对称相关性特征,3种不同Vine-copula模型对中国金融市场的拟合效果没有显著差异;多数两两市场间具有较高的非条件相关性,通过逐一分析除两两市场外的第3个市场对其相关性的影响得知,二者在某些市场条件下的条件相关性仅为其非条件相关性的20%以下,因而选择对应市场构建三元投资组合可以避免仅在两个市场同向投资时其市场价格同时下跌的风险;熊市时要避免直接在非条件相关性及条件相关性较强的市场间同向投资,应通过选择非条件相关性较低的两个市场、条件相关性表现独立或较低的多个市场构建投资组合,从而规避不同市场价格同时下跌的风险。 相似文献
970.
中国的人口素质逆淘汰问题不仅是多学科的研究对象,而且是学术界争论的焦点。本文从城乡不同的生育率是造成人口素质逆淘汰的原因出发,采取定性分析和定量分析相结合的方法,指出静态社会中的确存在人口素质逆淘汰,但城镇化不仅控制了人口数量,而且提高了人口素质,因此,加大高等教育的投入和改善医疗卫生条件等提高我国人口素质的根本途径应和推进城镇化相结合,才能达到事半功倍的效果。 相似文献