论新的安全观

新世纪以来，国际安全形势所呈现出的新特征对人类安全与可持续发展提出了新的挑战。传统以意识形态为主导的旧安全观经历着向新安全观的历史转变。新的安全观以资源安全为基点。以环境安全为保障，重点处理好经济安全与政治安全、军事安全等的关系，实现经济社会的可持续发展。树立新的安全观是实现可持续发展的内在要求。我国树立新的安全观，需要建立相应制度保障，主要包括：国家资源战略储备制度、政府危机管理的新型应急机制和资源环境国际合作机制等。     

A nonparametric test to compare survival distributions with covariate adjustment

Summary.  The analysis of covariance is a technique that is used to improve the power of a k -sample test by adjusting for concomitant variables. If the end point is the time of survival, and some observations are right censored, the score statistic from the Cox proportional hazards model is the method that is most commonly used to test the equality of conditional hazard functions. In many situations, however, the proportional hazards model assumptions are not satisfied. Specifically, the relative risk function is not time invariant or represented as a log-linear function of the covariates. We propose an asymptotically valid k -sample test statistic to compare conditional hazard functions which does not require the assumption of proportional hazards, a parametric specification of the relative risk function or randomization of group assignment. Simulation results indicate that the performance of this statistic is satisfactory. The methodology is demonstrated on a data set in prostate cancer.     

A Unified Approach to a Class of Stochastic Carcinogenesis Models

Survival and hazard functions play a pivotal role in carcinogenesis modeling. This paper provides a unified approach to computing these two quantities by classifying a large class of carcinogenesis models from a computational point of view, and prescribes specific computational recipes according to this classification.     

加快建立多层次的农村社会保障体系——义乌市东河经济社会发展研究分报告之三

本文在对义乌市东河农村社会保障现状评价的基础上,提出了建立东河农村社会保障体系的目标与重点,及其加强农村最低生活保障制度、医疗保险制度、养老保险制度和敬老院建设的对策与建议.     

Bayesian incidence analysis of animal tumorigenicity data

Statistical inference about tumorigenesis should focus on the tumour incidence rate. Unfortunately, in most animal carcinogenicity experiments, tumours are not observable in live animals and censoring of the tumour onset times is informative. In this paper, we propose a Bayesian method for analysing data from such studies. Our approach focuses on the incidence of tumours and accommodates occult tumours and censored onset times without restricting tumour lethality, relying on cause-of-death data, or requiring interim sacrifices. We represent the underlying state of nature by a multistate stochastic process and assume general probit models for the time-specific transition rates. These models allow the incorporation of covariates, historical control data and subjective prior information. The inherent flexibility of this approach facilitates the interpretation of results, particularly when the sample size is small or the data are sparse. We use a Gibbs sampler to estimate the relevant posterior distributions. The methods proposed are applied to data from a US National Toxicology Program carcinogenicity study.     

Non-homogeneous Markov models in the analysis of survival after breast cancer

A cohort of 300 women with breast cancer who were submitted for surgery is analysed by using a non-homogeneous Markov process. Three states are onsidered: no relapse, relapse and death. As relapse times change over time, we have extended previous approaches for a time homogeneous model to a non omogeneous multistate process. The trends of the hazard rate functions of transitions between states increase and then decrease, showing that a changepoint can be considered. Piecewise Weibull distributions are introduced as transition intensity functions. Covariates corresponding to treatments are incorporated in the model multiplicatively via these functions. The likelihood function is built for a general model with k changepoints and applied to the data set, the parameters are estimated and life-table and transition probabilities for treatments in different periods of time are given. The survival probability functions for different treatments are plotted and compared with the corresponding function for the homogeneous model. The survival functions for the various cohorts submitted for treatment are fitted to the mpirical survival functions.     

论政府社会保障政策能力建设

我国目前的社会保障形势非常严峻,为此必须大力加强政府社会保障政策能力建设。政府社会保障政策能力是指政府科学制定社会保障政策和执行社会保障政策的能力。为了切实提高政府社会保障政策能力,我们必须完善政府的社会保障政策问题发现机制、社会保障政策民主参与机制、社会保障政策执行机制、社会保障政策评估机制、社会保障政策决策者责任追究机制和社会保障政策调整机制,等等。     

改革开放以来我国社会保障问题研究的主要特点

改革开放以来,我国学术界对于社会保障问题的研究呈现出鲜明的时代特点,主要表现在:研究的起步较晚,内容上的极不均衡性,质量上的相对低劣性,对外研究上的自闭性与偏向性,发展上的趋热性和迅猛性等。国家相关政策法规的推动与社会发展的要求催生了社会保障研究的上述基本特点,同时也为社会保障研究的进一步发展奠定了制度基础与社会土壤。      

新生代农民工社会保障供求探析及协调解决——基于福州市258名新生代农民工的调查

从需求与供给双重视角对福建省福州市258名新生代农民工社会保障状况所进行的调查显示：新生代农民工对于社会保障有着较为强烈的需求,与此同时,近年来农民工社会保障供给状况也有了较大改善。但是,调查也表明：无论是新生代农民工社会保障的需求面还是供给面都受到多种因素的影响和制约,目前新生代农民工社会保障供需之间仍然存在着十分尖锐的矛盾,突出地表现在数量上的供不应求和性质上的供需脱节。要解决新生代农民工的社会保障问题,需要将新生代农民工社会保障的需求状况与供给状况相联系、相结合,理顺各种制约性要素,畅通供给渠道,创新供给模式,提高供给能力和供给效率。     

农民工收入地域差异对留守老人养老保障的影响

西部农民工选择到经济发达的东部城市务工以期获得理想的收入．用以改善家庭生活。然而就业地域的不同选择所引致的收入反差，使农民工不得不考虑其选择务工地区的距离和自身的成本。文章通过对以广东、安徽、甘肃三省为代表的在东、中、西三地区务工农民工收入的比较研究。结果表明西部地区农民工为获得理想的高收入而选择东部城市务工，实际中却是在东部城市务工收入要低于在中、西部城市的收入。并重点对这一困境如何对留守老人养老造成影响进行分析。