社会工作视野下的城市少数民族流动人口问题

城市少数民族流动人口问题正逐渐成为社会关注的一大热点,文章主要对城市少数民族流动人口的现状、特点,对城市发挥的积极功能和城市少数民族流动人口问题的具体表现作一概述,并从社会工作这一新的视角分析了城市少数民族流动人口问题的成因,在此基础上就社会工作如何介入此问题提出一些建议.     

浅析中国土族人口分布格局及其社会发展

人口分布格局,既是人在空间分布上呈现出来的地理状态,又是许多附着于分布环境上的社会人文变量的外在表现,因此对其进行研究具有探索自然和认识社会的双重意义。本文就中国土族人口的分布格局进行探讨,从历史和现实两方面分析了形成这种分布的原因,并在此基础上探讨了与人口分布格局密切相关的人口城市化、人口流动、人口素质提高、区域经济发展等社会热点问题,以期为政府政策的制定提供可靠的依据。     

Consistent Probabilistic Social Choice

Two fundamental axioms in social choice theory are consistency with respect to a variable electorate and consistency with respect to components of similar alternatives. In the context of traditional non‐probabilistic social choice, these axioms are incompatible with each other. We show that in the context of probabilistic social choice, these axioms uniquely characterize a function proposed by Fishburn (1984). Fishburn's function returns so‐called maximal lotteries, that is, lotteries that correspond to optimal mixed strategies in the symmetric zero‐sum game induced by the pairwise majority margins. Maximal lotteries are guaranteed to exist due to von Neumann's Minimax Theorem, are almost always unique, and can be efficiently computed using linear programming.     

Nonparametric Estimation of the Number of Drug Users in Hong Kong Using Repeated Multiple Lists

We update a previous approach to the estimation of the size of an open population when there are multiple lists at each time point. Our motivation is 35 years of longitudinal data on the detection of drug users by the Central Registry of Drug Abuse in Hong Kong. We develop a two‐stage smoothing spline approach. This gives a flexible and easily implemented alternative to the previous method which was based on kernel smoothing. The new method retains the property of reducing the variability of the individual estimates at each time point. We evaluate the new method by means of a simulation study that includes an examination of the effects of variable selection. The new method is then applied to data collected by the Central Registry of Drug Abuse. The parameter estimates obtained are compared with the well known Jolly–Seber estimates based on single capture methods.     

老龄化背景下社会养老服务体系需求研究 ——以滁州市为例

已有的以“居家为基础、社区为依托、机构为支撑”的社会养老服务体系实际运行中未达到预期效果,存在目标人群模糊, 核心功能不清等问题。通过滁州市居民养老服务需求的调查,构建需求=意愿×能力的模式,研究老人养老服务意愿,支付养 老服务的能力,提出以照护为核心,在居家养老基础上对空巢、独居老人加强社区综合平台的作用,突出高龄、失能、半失能老 人机构养老的支撑作用,引进社会力量,以满足老年人群多样化多层次需求     

Visualization for Large‐scale Gaussian Updates

In geostatistics and also in other applications in science and engineering, it is now common to perform updates on Gaussian process models with many thousands or even millions of components. These large‐scale inferences involve modelling, representational and computational challenges. We describe a visualization tool for large‐scale Gaussian updates, the ‘medal plot’. The medal plot shows the updated uncertainty at each observation location and also summarizes the sharing of information across observations, as a proxy for the sharing of information across the state vector (or latent process). As such, it reflects characteristics of both the observations and the statistical model. We illustrate with an application to assess mass trends in the Antarctic Ice Sheet, for which there are strong constraints from the observations and the physics.     

Diagnostics in elliptical regression models with stochastic restrictions applied to econometrics

We propose an influence diagnostic methodology for linear regression models with stochastic restrictions and errors following elliptically contoured distributions. We study how a perturbation may impact on the mixed estimation procedure of parameters in the model. Normal curvatures and slopes for assessing influence under usual schemes are derived, including perturbations of case-weight, response variable, and explanatory variable. Simulations are conducted to evaluate the performance of the proposed methodology. An example with real-world economy data is presented as an illustration.     

Choosing summary statistics by least angle regression for approximate Bayesian computation

Bayesian statistical inference relies on the posterior distribution. Depending on the model, the posterior can be more or less difficult to derive. In recent years, there has been a lot of interest in complex settings where the likelihood is analytically intractable. In such situations, approximate Bayesian computation (ABC) provides an attractive way of carrying out Bayesian inference. For obtaining reliable posterior estimates however, it is important to keep the approximation errors small in ABC. The choice of an appropriate set of summary statistics plays a crucial role in this effort. Here, we report the development of a new algorithm that is based on least angle regression for choosing summary statistics. In two population genetic examples, the performance of the new algorithm is better than a previously proposed approach that uses partial least squares.     

不同城市的房价是否具有相同的人口集聚效应——基于35个大中城市PVAR模型的实证分析

人口集聚会引起房价上涨,但不同类型的城市由于集聚人口的教育程度不同,房价上涨也具有不同的效应。首先建立人口流动理论模型分析人口集聚对房价上涨的影响,然后通过建立房价、人口集聚、房地产投资和人均可支配收入的PVAR模型进行实证分析。结论表明,一类城市人口集聚对房价上涨具有正效应,二类城市为平效应,三类城市为负效应;三类城市的房价上涨主要是房地产投资和人均收入提高所推动的。     

基于文献关键词统计分析的我国开放与远程教育研究现状探析

以中国知网（CNKI）为平台,利用共词分析方法,对2006年1月至2015年6月间公开发表在开放与远程教育领域期刊论文的关键词进行统计分析,结合SATI软件和UCINET软件进行数据处理,探讨高频关键词之间的内在联系,揭示我国开放与远程教育研究的主题结构和核心领域。结果表明：此间我国开放与远程教育领域主要存在七大研究主题;远程学习、网络课程、学习支持服务、学习者是该领域的研究核心;移动学习、内容分析、学习科学和远程学习者将成为未来的研究热点。