贵州人口老龄化,经济增长对养老保险支出影响实证研究

人口的老龄化是21世纪世界各国各地区的普遍趋势,人口老龄化问题及其对社会养老保障影响,已经引起社会各界的重视,成为国内外专家学者的研究热点。本文在利用2005年1%人口抽样和1991-2007统计数据分析贵州省人口老龄化现状及特征的基础上,运用协整分析方法,就贵州人口老龄化程度、经济增长对养老保险支出的影响做了定量探索,最后,结合现实情况和模型分析的结果对相关情况提出建议。     

西部地区人口红利效应与区域增长差距

本文从人口红利效应角度比较区域之间的增长差距,发现人口红利效应的发挥并非是经济增长的决定因素,经济增长还受制于其他因素的影响,人力资本投资和由知识积累及扩散获得的技术进步以及制度等其他要素从深层次上决定着区域差距的逐渐扩大。     

快速人口转变后的中国长期经济增长—从预期寿命、人力资本投资角度考察

在过去三十年里,中国历经了发达国家要用一百多年才能完成的人口转变过程。生育率、死亡率快速下降,接踵而至的是日益严重的少子、老龄化过程。基于以上背景,本文扩展了Diamond（1965）的基本叠代模型,以不确定性寿命为切入点,在个人的微观行为基础上,致力于分析以下问题：中国是否需要调整当前的计划生育政策;随着人口红利的逐渐消失,中国长期的经济增长如何持续。本文的分析结果显示,预期寿命与生育率、人力资本投资、储蓄率以及经济增长的关系是非单调性的。     

少数民族人口分布及其变动分析

本文基于2005年全国1％抽样调查数据,并结合历次人口普查资料,综合分析了我国少数民族人口分布及其变动趋势。一方面,我国少数民族人口分布的基本特点是在长期的历史过程中形成的,各民族人口的分布格局有着非凡的稳定性,即少数民族主要分布于西部内陆地区、居住相对集中、大多生活在农村。另一方面,随着经济社会的巨大发展,民族政策的变化,交通工具的日益发达,民族人口的再分布渐趋活跃。少数民族人口分布呈现向东部沿海地区扩散的态势,人口分布趋于分散,城市化进程加速。     

流动人口定居意愿的动态变化和内部差异——基于福建省4城市的调查

本文利用2002年和2006年在福建省4个主要人口流入城市进行的两次流动人口定居意愿调查资料,通过对这两个时点的数据进行对比分析,考察了流动人口定居意愿的变化情况。分析结果表明,大部分流动人口尚未有在流入地长久定居的打算,但与2002年相比,2006年打算在流入地定居的流动人口所占的比重有所上升;流动人口内部在定居意愿及其变化上存在较明显的差异。这些结果为掌握流动人口的流迁动态并在此基础上制定相关政策提供了重要参考依据。     

深圳市人口承载力分析及对策研究

本文运用系统动力学的方法。综合分析了在不同方案下土地与水等资源性因素对深圳未来人口承载力的影响。并根据对不同方案的结果以及它们对深圳城市发展的影响的评价,从人口、资源环境、政策法律和产业结构等方面提出了缓解深圳人口承载压力的政策建议。     

Early-summer inhibition of reproduction in wild white-footed mice ( Peromyscus leucopus noveboracensis ): influence of supplemental food

Adults of wild white-footed mouse (Peromyscus leucopus noveboracensis) populations in southeastern Virginia have been shown to be reproductively suppressed during May–July compared with other months of the reproductive season. The gonads and sex accessory glands are also significantly smaller during May–July than at other times of the year. The causes of this early summer reproductive suppression are unknown. In this study, food (Agway 3000) that could not be hoarded was supplied in feeding stations on one-half the 11-ha wooded study area during 1990 and 1991. Food consumption (g) was positively but not significantly correlated with population density (adults/ha) during both years. Population density was higher during 1991 on the food-supplemented area than on the nonsupplemented area, but the statistical significance was marginal. Mice of both sexes living on both areas during 1990 and 1991 exhibited significant reproductive suppression during May–June. Further, mice of both sexes living on both areas during both years had significantly smaller gonads and sex accessory glands during May–June compared with other months of the year. Thus, during both years, surplus food did not prevent suppression of reproductive function in this wild population, and this phenomenon remains unexplained. Received: November 4, 1998 / Accepted: October 5, 1999     

Theoretical considerations on the C-D effect in self-thinning plant populations

A model for describing the competition–density (C-D) effect in self-thinning populations was developed on the basis of the following three basic assumptions: (1) the growth of mean phytomass follows a general logistic equation; (2) final yield is independent of initial population density; and (3) there exists a functional relationship between actual and initial population densities at any given time. The resultant equation takes the same reciprocal form as the reciprocal equation of the C-D effect derived from Shinozaki–Kira's theory (i.e., the logistic theory of the C-D effect), which deals with the density effect in nonself-thinning populations. However, one of the two time-dependent coefficients is quite different in mathematical interpretation between the two reciprocal equations. The reciprocal equation for self-thinning populations is essentially the same as the reciprocal equation assumed in the derivation of the functional relationship between actual and initial population densities. The establishment of the reciprocal equation is supported by the empirical facts that the reciprocal relationship between mean phytomass and population density is discernible in not only nonself-thinning populations but also in self-thinning populations. The present model is expected to systematically interpret underlying mechanisms between the C-D effect, which is observed at a time constant among populations with various initial densities, and self-thinning, which is observed along a time continuum in a given population. Received: August 5, 1998 / Accepted: January 7, 1999     

我国各地区人口与经济协调发展的分类研究

人口与经济的协调发展是我国可持续发展的关键之所在 ,本文利用现代统计分析中的Ward最小方差聚类分析法 ,对我国各省、市、自治区人口与经济协调发展状况进行了全面而深入的分类研究 ,得到了相应的的分类模型和分类结果 ,从而为探讨我国各地区人口与经济协调发展的内在联系和发展模式提供较科学的依据     

我国流动人口基本态势研究

流动人口是一种广义迁移人口,利用四普资料抽样数据和 1995年全国 1％抽样调查资料,本文研究了我国流动人口分类和原因,流入、流出地的分布、流动人口的年龄性别构成、婚姻状态、文化、职业分布等。