检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

关注知识属性的化学知识结构化教学

化学教学 2024年第4期 3-8页

作者：邹国华福建省龙岩第一中学福建龙岩364000

知识是有结构的,导向知识结构化的教学,其目标是使事实、概念性知识到方法性知识再到核心观念的发展,以知识结构化促进知识转化为能力和素养;知识具有多维属性,关注知识的多维属性,有助于理解知识的学科本质及其隐含的方法、核心观念,... 详细信息

知识是有结构的,导向知识结构化的教学,其目标是使事实、概念性知识到方法性知识再到核心观念的发展,以知识结构化促进知识转化为能力和素养;知识具有多维属性,关注知识的多维属性,有助于理解知识的学科本质及其隐含的方法、核心观念,关注知识属性的化学教学有利于实现知识的结构化。

关键词：知识结构知识属性化学教学

在线全文

学校读者我要写书评

暂无评论

水族馆短视频营销的现状、问题与对策

中国水产 2024年第9期586卷 58-60页

作者：邹国华鲸骑士(上海)文化传播有限公司

随着移动互联网快速发展,短视频因创作流程简单、传播速度快、与受众互动性强等优势在互联网平台迅速传播并保持活跃。水族馆作为文旅和科普载体,在短视频赛道也进行了新尝试。本文简要阐述与分析了水族馆短视频营销方面的现状和问题,... 详细信息

随着移动互联网快速发展,短视频因创作流程简单、传播速度快、与受众互动性强等优势在互联网平台迅速传播并保持活跃。水族馆作为文旅和科普载体,在短视频赛道也进行了新尝试。本文简要阐述与分析了水族馆短视频营销方面的现状和问题,并针对性地提出相关对策,以期为水族馆短视频营销行业健康发展提供参考借鉴。

关键词：视频营销水族馆短视频互联网平台移动互联网传播速度创作流程问题与对策

维普期刊数据库博看期刊

Average Estimation of Semiparametric Models for High-Dimensional Longitudinal Data

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2020年第6期33卷 2013-2047页

作者： ZHAO Zhihao zou guohua School of Mathematicnl Sciences Capital Normal UniversityBeijing 100048China

Model average receives much attention in recent *** paper considers the semiparametric model averaging for high-dimensional longitudinal *** minimize the prediction error,the authors estimate the model weights using a leave-subject-out cross-validation *** optimality of the proposed method is proved in the sense that leave-subject-out cross-validation achieves the lowest possible prediction loss *** studies show that the performance of the proposed model average method is much better than that of some commonly used model selection and averaging methods.

关键词： Asymptotic optimality high-dimensional longitudinal data leave-subject-out cross-validation model averaging semiparametric models

Least Squares Model Averaging for Two Non-Nested Linear Models

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2023年第1期36卷 412-432页

作者： GAO Yan XIE Tianfa zou guohua Department of Statistics College of ScienceMinzu University of ChinaBeijing 100081China Faculty of Science Beijing University of TechnologyBeijing 100124China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

This paper studies the least squares model averaging methods for two non-nested linear *** is proved that the Mallows model averaging weight of the true model is root-n *** the authors develop a penalized Mallows criterion which ensures that the weight of the true model equals 1 with probability tending to 1 and thus the averaging estimator is asymptotically *** neither candidate model is true,the penalized Mallows averaging estimator is asymptotically *** results show the selection consistency of the penalized Mallows method and the superiority of the model averaging approach compared with the model selection estimation.

关键词： Asymptotic optimality consistency least squares model averaging non-nested models

在线全文

学校读者我要写书评

暂无评论

中国罗非鱼出口贸易现状、问题及对策分析

全国流通经济 2024年第6期 57-60页

作者：吕屹云邹国华仲恺农业工程学院经贸学院广东广州510225

在全球罗非鱼出口贸易市场上,中国是世界上最大的罗非鱼产品出口国,通过分析我国罗非鱼的出口贸易情况,对于推动我国罗非鱼出口贸易更好地发展具有一定的意义。本文整理中国水产品进出口贸易统计年鉴的数据,通过分析2011—2021年中国罗... 详细信息

在全球罗非鱼出口贸易市场上,中国是世界上最大的罗非鱼产品出口国,通过分析我国罗非鱼的出口贸易情况,对于推动我国罗非鱼出口贸易更好地发展具有一定的意义。本文整理中国水产品进出口贸易统计年鉴的数据,通过分析2011—2021年中国罗非鱼出口量和出口额、各品种的出口情况、各主要省份的罗非鱼产品出口现状和出口市场情况进行了分析。分析发现,近年来我国罗非鱼出口量及出口额呈现波动上涨的趋势,出口的主要产品从冻罗非鱼逐渐转变成制作或保藏好的罗非鱼。广东省作为中国罗非鱼的主要产地,一直保持着中国罗非鱼出口第一大省的地位,罗非鱼产品主要出口到美国、墨西哥、科特迪瓦等国家。同时,中国罗非鱼出口贸易中也存在着一些问题,例如出口产品质量不达标、出口目标市场过于集中、品牌建设不足,附加值低等。最后,本文针对存在的问题提出建议对策,以期推动中国罗非鱼产业和出口贸易更好地发展。

关键词：罗非鱼出口贸易产品质量

Frequentist model averaging for linear mixed-effects models

在线全文

学校读者我要写书评

暂无评论

Frontiers of Mathematics in China 2013年第3期8卷 497-515页

作者： Xinjie CHEN guohua zou Xinyu ZHANG Academy of Mathematics and Systems Science Chinese Academy Of SciencesBeijing 100190 China Center for Forecasting Science Chinese Academy of Sciences Beijing 100190 China

Linear mixed-effects models are a powerful tool for the analysis of longitudinal data. The aim of this paper is to study model averaging for linear mixed-effects models. The asymptotic distribution of the frequentist model average estimator is derived, and a confidence interval procedure with an actual coverage probability that tends to the nominal level in large samples is developed. The two confidence intervals based on the model averaging and based on the full model are shown to be asymptotically equivalent. A simulation study shows good finite sample performance of the model average estimators.

关键词： Asymptotic equivalence asymptotic normality mixed-effectsmodels model averaging

指向思维培养发展模型认知——以高三“电化学专题”第一轮复习为例

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中小学教学研究 2024年第3期25卷 90-96页

作者：廖思彬邹国华郑璇福建省龙岩第一中学

在高三专题复习中,存在知识点浅层回顾、过度依赖教辅、机械刷题等问题,针对这些问题提出了设计任务驱动、指向思维培养、发展模型认知的高三专题复习模式。以高三“电化学专题”第一轮复习为例,分析了“电化学”促进学生思维发展的功... 详细信息

在高三专题复习中,存在知识点浅层回顾、过度依赖教辅、机械刷题等问题,针对这些问题提出了设计任务驱动、指向思维培养、发展模型认知的高三专题复习模式。以高三“电化学专题”第一轮复习为例,分析了“电化学”促进学生思维发展的功能价值,阐述了电化学教学的重点和难点,指出了学生主要的思维障碍点,提出了促进学生电化学思维模型建构的策略。

关键词：思维培养模型认知电化学专题教学设计

Choice of weights in FMA estimators under general parametric models

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2013年第3期56卷 443-457页

作者： ZHANG XinYu zou guohua LIANG Hua Academy of Mathematics and Systems Science Chinese Academy of Sciences Center for Forecasting Science Chinese Academy of Sciences Department of Biostatistics and Computational Biology University of Rochester Medical Center

The choice of weights in frequentist model average estimators is an important but difficult problem. Liang et al. (2011) suggested a criterion for the choice of weight under a general parametric framework which is termed as the generalized OPT (GOPT) criterion in the present paper. However, no properties and applications of the criterion have been studied. This paper is devoted to the further investigation of the GOPT criterion. We show that how to use this criterion for comparison of some existing weights such as the smoothed AIC-based and BIC-based weights and for the choice between model averaging and model selection. Its connection to the Mallows and ordinary OPT criteria is built. The asymptotic optimality on the criterion in the case of non-random weights is also obtained. Finite sample performance of the GOPT criterion is assessed by simulations. Application to the analysis of two real data sets is presented as well.

关键词： asymptotic optimality likelihood inference model averaging model selection model selection diagnostics

Post-J test inference in non-nested linear regression models

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2015年第6期58卷 1203-1216页

作者： CHEN XinJie FAN YanQin WAN Alan zou guohua Academy of Mathematics and Systems Science Chinese Academy of Sciences Department of Economics Vanderbilt University Department of Management Sciences City University of Hong Kong School of Mathematical Sciences Capital Normal University

This paper considers the post-J test inference in non-nested linear regression models. Post-J test inference means that the inference problem is considered by taking the first stage J test into account. We first propose a post-J test estimator and derive its asymptotic distribution. We then consider the test problem of the unknown parameters, and a Wald statistic based on the post-J test estimator is proposed. A simulation study shows that the proposed Wald statistic works perfectly as well as the two-stage test from the view of the empirical size and power in large-sample cases, and when the sample size is small, it is even better. As a result,the new Wald statistic can be used directly to test the hypotheses on the unknown parameters in non-nested linear regression models.

关键词： non-nested linear regression post-J test Wald statistic