求拟合曲线的一种代数方法

文本介绍一种十分简捷的代数方法,给出一个求拟合曲线的系数公式。该方法与回归分析中常用的方法相比更简便适用。     

融资融券交易对中国上市公司研发支出的影响研究

研发活动是一项高风险的长期投资,上市公司从事研发活动面临着股东与经理之间的委托代理问题。选择融资融券半自然实验,采用DID回归方法和PSM-DID方法检验融资融券交易对中国上市公司研发支出的影响,结果表明融资融券交易会提高研发支出。考虑融资融券交易规模的影响,结果依然稳健。最后检验融资融券对研发的影响渠道,结果表明融资融券会通过降低公司股票的信息不对称来提高公司的研发支出。     

中国健康老年前期人血沉参考值与地理因素的多元回归分析

为制定中国健康老年前期人血沉参考值的统一标准提供科学依据 ,本文收集了中国各地用温氏法测定的健康老年前期人血沉参考值 ,并对其与地理因素的关系进行了研究 ,发现海拔高度是影响健康老年前期人血沉参考值最主要的因素 ,海拔高度与健康老年前期人血沉参考值的负相关性很显著 .用多元回归分析的方法推导出了两个回归方程 .如果知道了中国某地的地理因素 ,就可以用这两个回归方程估算该区的健康老年前期人血沉参考值     

联合预测在中国人口总量预测中的应用

人口问题是制约中国经济发展的重大问题之一,实行计划生育以来,我国的人口增长水平虽然放缓,但由于人口基数庞大,人口的增长数量仍然相当的可观,因此,准确的预测未来总人口数量对于制定相应的政策法规以保证经济的快速发展具有重大意义。基于过去年份的人口数据,利用ARIMA模型和回归模型来预测未来中国的人口数量,并利用联合预测将两种预测结果进行加权平均,以达到更高的预测精度,为人口预测提供了一种简单高效的预测模型。     

农用地收益相关影响因素分析

通过农地收益的影响因素的分析,建立以农地收益为被解释变量,以其它定量的影响因素为解释变量的多元非线性回归模型,并对保留和剔除的变量作经济分析,并针时影响农地收益的主要影响因素提出一些可供参考的意见.     

Statistical analyses in the physiology of exercise and kinanthropometry

Research into the physiology of exercise and kinanthropometry is intended to improve our understanding of how the body responds and adapts to exercise. If such studies are to be meaningful, they have to be well designed and analysed. Advances in personal computing have made available statistical analyses that were previously the preserve of elaborate mainframe systems and have increased opportunities for investigation. However, the ease with which analyses can be performed can mask underlying philosophical and epistemological shortcomings. The aim of this review is to examine the use of four techniques that are especially relevant to physiological studies: (1) bivariate correlation and linear and non-linear regression, (2) multiple regression, (3) repeated-measures analysis of variance and (4) multi-level modelling. The importance of adhering to underlying statistical assumptions is emphasized and ways to accommodate violations of these assumptions are identified.     

基于游客感知的节事旅游形象影响因素实证分析——以开封菊花花会为例

为了得知节事旅游形象各影响因素之间的逻辑层次关系以及各影响因素的重要程度,本文以河南省开封菊花花会为研究对象进行实证,运用SPSS17.0因子法对各影响因素进行定量评价。因子分析得出影响节事旅游形象的四个公因子,并通过回归分析,按照重要程度排列依次是:游览价值、社会环境、设施环境和旅游环境。     

Does promoting school attendance reduce child labor? Evidence from Burkina Faso's BRIGHT project

Using data from BRIGHT, an integrated program that aims to improve school participation in rural communities in Burkina Faso, we investigate the impact of school subsidies and increased access to education on child work. Regression discontinuity estimates demonstrate that, while BRIGHT substantially improved school participation, it did not reduce – in fact may have increased – children's participation in economic activities and household chores. This combination of increased school participation and work can be explained by the introduction of a simple non-convexity in the standard model of altruistic utility maximizing households. If education programs are implemented to achieve a combination of increased school participation and a reduction in child work they may either have to be combined with different interventions that effectively reduce child work or they may have to be tuned more carefully to the incentives and constraints the child laborer faces.     

According to Plan? Examining the Intended and Unintended Treatment Effects of EL Classification in Early Elementary and the Transition to Middle School

Abstract

Research has demonstrated that classification as an English learner (EL) is consequential for students, with important effects on educational achievement and attainment. Yet we know little about the mechanisms that underlie the effects of EL classification. This study explores whether, and to what extent, EL classification results in the treatments it is designed to trigger, and also whether, and to what extent, EL classification triggers unintended treatments. The study uses longitudinal school district data and regression discontinuity analyses to evaluate the treatment effects of EL classification. It examines two moments: initial classification as students enter kindergarten, and retained EL classification as students transition into middle school. Findings suggest that EL classification, for students near the margin of classification, results in many treatments it is intended to trigger including language assessments in early elementary, and English language development instruction and modified content instruction in middle school. In addition, findings show that EL classification triggers two unintended treatments among students; Classification limits access to English speaking peers in early elementary, and negatively impacts enrollment in a full academic course load in middle school.     

汉英回文修辞格对比研究

要使语言生动形象,具有说服力和感染力,以便准确清楚有力地表达思想,必须采用修辞技巧来美化语言。汉英回文修辞格的普遍使用,使语言产生节律感,有效地揭示了事物、情理之间的关系。本文尝试对汉英回文格进行对比研究,探索它们各自不同的结构分类特征,并对它们在两种不同语言中的形成原因作出语言学的阐释。