Particle Swarm Optimization based predictive control of Proton Exchange Membrane Fuel Cell （PEMFC）

INTRODUCTION Fuel cells have attracted more attention in the last few years due to scarcity of the world energy source. The Proton Exchange Membrane Fuel Cell (PEMFC) is the focus of current development efforts because it is capable of higher power density and faster start-up than other fuel cells (Zhang et al., 2004). Research emphasis is on high power density with adequate energy conversion efficiency. PEMFC performance is related to many factors, among which electrolyte membrane …     

A VBA‐based Simulation for Teaching Simple Linear Regression

In spite of the name, simple linear regression presents a number of conceptual difficulties, particularly for introductory students. This article describes a simulation tool that provides a hands‐on method for illuminating the relationship between parameters and sample statistics.     

体育价值观与大学生体育锻炼行为的关系探讨

通过随机抽样调查了209名大学生体育价值观与体育锻炼行为之间的关系,并对样本数据进行描述统计分析、因子分析、相关分析和线性回归分析,实证研究表明：体育价值观及其各因素与大学生体育锻炼行为两者之间存在显著的线性回归关系。理论拓展认为,体育锻炼行为的发生一方面得益于体育价值观内在驱动力的诱发作用,另一方面也是建立在客体环境上外因合力的结果。建议在大学体育教学中重视对学生体育价值观的培养,从而引导他们积极参与体育锻炼,增强学生的身体素质。     

Illustrating Regression Concepts

Modern microcomputers offer attractive possibilities to illustrate various concepts related to regression. In this article we describe how this can be achieved.     

本溪地区人口预测的数学模型

根据回归分析和灰色系统理论，利用本溪地区1990－1999年人口总数的统计资料，建立了本溪地区人口总数预测的数学模型，并通过对本溪地区人口总数预测的数学模型，验证了使用本文介绍的方法所得到的预测结果是较为符合实际的。     

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     

Incentives for teacher relocation: Evidence from the Gambian hardship allowance

We evaluate the impact of the Gambian hardship allowance, which provides a salary premium of 30–40% to primary school teachers in remote locations, on the distribution and characteristics of teachers across schools. A geographic discontinuity in the policy's implementation and the presence of common pre-treatment trends between hardship and non-hardship schools provide sources of identifying variation. We find that the hardship allowance increased the share of qualified (certified) teachers by 10 percentage points. The policy also reduced the pupil–qualified teacher ratio by 27, or 61% of the mean, in recipient schools close to the distance threshold. Further analysis suggests that these gains were not merely the result of teachers switching from non-hardship to hardship schools. With similar policies in place in more than two dozen other developing countries, our study provides an important piece of evidence on their effectiveness.     

Do children spend too much time in schools? Evidence from a longer school year in Indonesia

I examine the effects of a longer school year in Indonesia on grade repetition, educational attainment, employability, and earnings. I exploit an arbitrary rule that assigned students to a longer school year in Indonesia in 1978–1979, which fits a fuzzy regression discontinuity design. I find the longer school year decreases the probability of grade repetition and increases educational attainment; it also increases the probability of working in formal sectors and wages later in life. These results suggest the length of school years in Indonesia is not too long.