篮球运动的高度与速度动态均衡规律

研究表明，篮球运动高度与速度的发展变化表现为：高度与速度不均衡-均衡-新的不均衡-新的均衡的动态均衡规律。实证分析发现，篮球运动的高度发展特点为：队伍位置身高不断完善，身高基础上更全面的身体素质，高度与体重、力量结合；速度发展特点是：注重内在的快，快赋于变的内容，强调快与慢的节奏。进一步研究表明，高度与速度对篮球运动的发展具有不同的作用：高度的提高使篮球运动的对抗强度增大；速度的提高使得篮球运动的技巧提高；高度与速度必须均衡发展。     

对森林绿化带体育休闲设施建设的探讨

主要运用文献资料、专家访谈、比较研究等方法,分析了上海森林绿化带体育休闲设施建设的必要性和可行性,对森林绿化带体育休闲设施的建设进行了理论上的构建,指出其建设过程中应处理好几种关系,并对此提出了意见和建议。     

匈奴史事与北方森林植被

这篇章根据历史记载，结合考古研究成果、岩画石刻以及孢子花粉分析结果等，大致勾勒了先秦两汉时期匈奴驻牧地区-现今祖国北方的森林植被状况，供大家与现在相同地区的自然环境状况比较。本的写作目的，就是要利用古今植被状况的巨大变化和强烈反差，来警示人们对生态环境的冷漠和麻木，唤起国民保护草木植被的紧迫责任感和实际行动。     

广东民族地区林区当前状况的考察及思考

本文论述了在国家林业政策转变的情况下，在市场经济的大环境里，广东民族地区林区生产、生活现状，存在的突出问题及解决的措施和方法，并尝试探讨广东省民族地区林业发展问题。     

Parameter Estimation Accuracy of the Effort-Moderated Item Response Theory Model Under Multiple Assumption Violations

As low-stakes testing contexts increase, low test-taking effort may serve as a serious validity threat. One common solution to this problem is to identify noneffortful responses and treat them as missing during parameter estimation via the effort-moderated item response theory (EM-IRT) model. Although this model has been shown to outperform traditional IRT models (e.g., two-parameter logistic [2PL]) in parameter estimation under simulated conditions, prior research has failed to examine its performance under violations to the model’s assumptions. Therefore, the objective of this simulation study was to examine item and mean ability parameter recovery when violating the assumptions that noneffortful responding occurs randomly (Assumption 1) and is unrelated to the underlying ability of examinees (Assumption 2). Results demonstrated that, across conditions, the EM-IRT model provided robust item parameter estimates to violations of Assumption 1. However, bias values greater than 0.20 SDs were observed for the EM-IRT model when violating Assumption 2; nonetheless, these values were still lower than the 2PL model. In terms of mean ability estimates, model results indicated equal performance between the EM-IRT and 2PL models across conditions. Across both models, mean ability estimates were found to be biased by more than 0.25 SDs when violating Assumption 2. However, our accompanying empirical study suggested that this biasing occurred under extreme conditions that may not be present in some operational settings. Overall, these results suggest that the EM-IRT model provides superior item and equal mean ability parameter estimates in the presence of model violations under realistic conditions when compared with the 2PL model.     

基于Bootstrap法的核估计逼近

从分布密度函数为f的总体中抽取独立同分布的样本X1,…,Xn,μ=EX1研究密度泛函θ=f(μ)的核型估计fn()的Bootstrap逼近问题.     

Likelihood-Based Confidence Intervals in Exploratory Factor Analysis

In exploratory or unrestricted factor analysis, all factor loadings are free to be estimated. In oblique solutions, the correlations between common factors are free to be estimated as well. The purpose of this article is to show how likelihood-based confidence intervals can be obtained for rotated factor loadings and factor correlations, by applying maximum likelihood factor analysis subject to scaling and rotation constraints. As an illustrative example, an oblique 5-factor model will be fitted to the variance-covariance matrix of the 30 personality facets measured by the Revised NEO Personality Inventory, and confidence intervals will be estimated for all factor loadings and factor correlations, as well as for the associated reliability and validity coefficients.     

关于单一简单问题的学生团体反应时间分布参数估计与运用

介绍在计算机局域网环境条件下进行单一简单问题测试,收集学生团体的反应时间分布数据并加以处理的基本方法,给出时间反应分布参数的矩估计结果,初步探讨学生团体反应信息的有效运用问题。     

遥感技术在农业生产中的应用研究

遥感技术既是一种准确的对地观测技术。又是一种有效的信息获取手段。农业是遥感应用中最成功的领域之一。遥感技术和计算机技术结合应用。已经使农业研究从经验水平提高到理论水平,使农业生产进入到定量化、精准化和机理化的新阶段。     

基于MATLAB的赫尔默特方差分量估计法实现

本文通过对赫尔默特方差分量估计法的理论、模型和算法的研究,应用MATLAB平台,使用MATLAB语言编写程序,开发出通用的模块,制作可视化界面,操作简单,减少了测绘工作的内业工作量,提高了工作效率,并可作为其他平差问题编程的参考,此模块具有极高的实际意义和应用价值。