中国门巴族未来人口预测与民族地区经济发展研究

根据“五普”数据显示,我国少数民族人口为106430000人,占全国总人口的8.41%。虽然少数民族整体人数相对较少,但对少数民族地区的社会、经济发展起着重要的作用。本文采用因素法模型对我国人口数量较少的门巴族未来人口进行预测,分析未来50年门巴族人口的发展状况以及对民族地区经济发展的影响,对少数民族人口可持续发展,以及对民族地区社会经济发展有着重要的意义,为国家制定少数民族尤其是人口数量较少的少数民族人口发展规划提供政策依据,也有利于少数民族地区人口、社会与经济的和谐发展。     

宁夏人口死亡率成因分析

宁夏人口死亡率自2000年以来连续7年低于5‰,为全国最低水平。本文从建国以来宁夏人口死亡率的变化特征、从经济社会发展水平、人们的生活方式、人口的年龄构成等方面对宁夏人口死亡率偏低原因进行深入的分析,为各级领导决策提供科学的政策理论依据。     

人口红利与人口负债:数量界定、经验观察与理论思考

本文对人口红利与人口负债的概念、由来与数量界定进行了必要的理论阐述,构建了人口红利与人口负债的判别标准,对法国、日本与中国人口红利与人口负债演变的历史、现状与未来前景进行了比较分析,最后对人口红利与人口负债相关问题进行了理论上的探讨。     

Population, nutrition and agriculture

The human carrying capacity of the world or a country is considered as a function of food consumption per capita. A method of assessing carrying capacity is described, and it is shown that the world’s population currently exceeds the global carrying capacity, that the population of the less-developed countries (LDCs) exceeds their carrying capacity, and that this situation cannot be expected to change more than marginally in the period up to 2050. It is also shown that a major increase in the global consumption of nitrogen fertilizer will be necessary if world crop production per capita is to be maintained at the current inadequate level.     

中小企业的云创新流程研究

中小企业是我国国民经济和社会发展的重要基础,创新是其获得竞争优势和实现可持续发展的关键。然而,由于规模小、资金少、人才少等问题使其创新受到严重的阻碍。云创新作为一种更加开放的创新模式,在一定程度上可以促进中小企业创新。基于此,以组织流程为切入点,对中小企业的云创新流程进行了梳理。研究表明,中小企业的云创新要经过收集信息并界定问题、选择云平台和征集方案、参与者提供方案、筛选创新方案、反馈和优化满意方案,以及实施云创新方案等步骤,云创新流程的研究对中国中小企业健康发展有一定指导意义。     

A Conditionally Unbiased Estimator for the Equal-Catchability Model

ABSTRACT

In this article we reconsider an estimator of population size previously advocated for use when sampling from a population subdivided into different types. We show that it may be usefully adopted in the simple equal-catchability model used in mark-recapture. Unlike the commonly used maximum likelihood estimator, this conditionally unbiased estimator is always finite-valued. Except in situations in which the data contain little relevant information, its performance, in terms of bias and precision, is seen to be at least as good as that of the maximum likelihood estimator. Two estimators of the standard deviation of the conditionally unbiased estimator are considered.     

APPROXIMATION OF EXCEEDANCE PROCESSES IN LARGE POPULATIONS

We consider a population of n individuals. Each of these individuals generates a discrete time branching stochastic process. We study the number of ancestors S(n,t) whose offspring at time t exceeds level θ(t), where θ(t) is some positive valued function. It is proved that S(n,t) may be approximated as t → ∞ and n → ∞ by some stochastic processes with independent increments.

     

中国人口年龄结构与居民医疗保健消费

本文借助中国2001—2010年的省级面板数据,运用动态面板GMM估计方法,考察了中国人口年龄结构(少儿和老年抚养系数)变化对居民医疗保健消费支出的影响。结果发现,中国少儿抚养系数对居民医疗保健消费支出的影响不显著;老年抚养系数对居民医疗保健消费支出有正影响,即老年抚养系数的上升会带动居民人均医疗保健消费支出的增加。此外,本文还发现,医疗保健消费支出的滞后一期系数都为正,系统GMM两步估计系数为0.51,表明居民医疗保健消费支出存在较强的惯性;人均收入增长对居民医疗保健消费支出有正向的显著影响。     

Effects of Rotation Group Bias on Estimation of Unemployment

Previous analysis of rotation group bias in the Current Population Survey has concluded that if the biases are additive, the ratio and composite estimators of month-to-month change in unemployment are unbiased. This article shows that if the biases contain a multiplicative aspect, both estimators of change are then biased. The article also presents some empirical results that cast doubt on the validity of a purely additive model.     

面向数据流的土地适宜性评价系统设计与实现

土地适宜性评价是将评价原始资料进行分析处理得到土地相对于特定用途的适宜程度。针对土地适宜性评价必须按照一定的流程展开工作的特点,文章将面向数据流的系统分析和设计方法运用于土地适宜性评价中,通过对土地适宜性评价系统数据分析,结构设计,最终采用全组件式G IS软件SuperM ap Ob jects2003实现土地适宜性评价系统,从而提高了土地适宜性评价的效率和准确性。