A working estimating equation for spatial count data

This paper proposes a working estimating equation which is computationally easy to use for spatial count data. The proposed estimating equation is a modification of quasi-likelihood estimating equations without the need of correctly specifying the covariance matrix. Under some regularity conditions, we show that the proposed estimator has consistency and asymptotic normality. A simulation comparison also indicates that the proposed method has competitive performance in dealing with over-dispersion data from a parameter-driven model.     

求解非线性方程的一个全局收敛算法

首先将求非线性方程的解的问题转化为相应区间上的全局最优化问题,在迭代产生的当前点处通过构建一个辅助函数,并寻求辅助函数的局部极小点,逐步求出非线性方程满足一定精度的解.由此给出了一种求解非线性方程新的全局最优化方法,证明了算法的收敛性,并给出了算法的数值结果.     

算子方程A~nX(A~*)~n=B的解

利用算子矩阵分块技巧,在算子A值域闭的情况下研究了算子方程AnX(A*)n=B的解及正解的存在性,最后给出了正解的一般结构.     

基于GFRP OFBG筋的桥梁缆索索力测量技术研究

基于内嵌光纤Bragg光栅传感器的光纤光栅 玻璃纤维增强塑料复合筋（GFRP OFBG筋）,研究了GFRP OFBG筋自身的应变和温度传感特性,研究结果表明,GFRP OFBG智能筋具有优异的线性传感性能,筋中光栅测量的应变极限达12 000 με以上,波长变化达14 nm;对于用GFRP OFBG筋替换普通钢绞线的中丝而得到的GFRP OFBG智能钢绞线,进行了应变传感、温度敏感和钢绞线松弛试验,试验结果表明,GFRP OFBG智能钢绞线具有优异的线性传感性能和较低的应力松弛率,并可实现钢绞线受载全过     

空间数据分析的发展

空间统计学是研究空间问题的一门学科,它是应用数学快速发展的一个分支。尽管传统的数据分析中有许多很好的方法,但却不能完全地套用于空间数据的分析。空间模型的估计不仅与各种回归形式的假设有关,而且还与空间相关、空间异质的特性有关。从空间模型及推断、适应性估计、非参数回归、空间不相关性检验几个方面研究了空间数据分析方法的发展以及未来的趋势。     

西部地区农民养老模式选择意愿的影响因素分析——基于有序Probit模型和结构方程模型的实证研究

基于微观调查数据,利用有序Probit模型和结构方程模型对影响中国西部地区农民养老模式选择意愿的因素进行了系统分析。研究发现：西部地区农民倾向于选择依靠家庭和自我相结合的养老模式。潜变量个人禀赋、家庭特征、认知程度对农民养老模式选择意愿的影响显著,而社区特征的影响不显著;可观测变量年龄、健康状况、文化程度、从事职业、家庭男孩数、家庭生活水平、是否听说过新农保、是否听说过商业养老保险等对农民养老模式选择意愿的影响显著,而性别、婚姻状况、个人年收入、家庭人口数、家庭女孩数、家庭劳动力数、家庭承包土地数、离最近公路距离、离最近县城距离等变量对农民养老模式选择意愿并无显著影响。     

A multivariate time series model for the analysis and prediction of carbon monoxide atmospheric concentrations

We use a Bayesian multivariate time series model for the analysis of the dynamics of carbon monoxide atmospheric concentrations. The data are observed at four sites. It is assumed that the logarithm of the observed process can be represented as the sum of unobservable components: a trend, a daily periodicity, a stationary autoregressive signal and an erratic term. Bayesian analysis is performed via Gibbs sampling. In particular, we consider the problem of joint temporal prediction when data are observed at a few sites and it is not possible to fit a complex space–time model. A retrospective analysis of the trend component is also given, which is important in that it explains the evolution of the variability in the observed process.     

Spatial prediction and temporal backcasting for environmental fields having monotone data patterns

The authors develop a methodology for predicting unobserved values in a conditionally lognormal random spatial field like those commonly encountered in environmental risk analysis. These unobserved values are of two types. The first come from spatial locations where the field has never been monitored, the second, from currently monitored sites which have been only recently installed. Thus the monitoring data exhibit a monotone pattern, resembling a staircase whose highest step comes from the oldest monitoring sites. The authors propose a hierarchical Bayesian approach using the lognormal sampling distribution, in conjunction with a conjugate generalized Wishart distribution. This prior distribution allows different degrees of freedom to be fitted for individual steps, taking into account the differential amounts of information available from sites at the different steps in the staircase. The resulting hierarchical model is a predictive distribution for the unobserved values of the field. The method is demonstrated by application to the ambient ozone field for the southwestern region of British Columbia.     

走向边缘的精神之旅──论李伯元的思想倾向及其演进过程

晚清时期 ,中国新型的知识分子开始出现。由于受到特殊历史情境的制约 ,他们的人生道路和思想倾向大多带有强烈的政治色彩。然而 ,也有部分人由社会中心逐渐走向了社会的边缘 ,以独立的批判者形象显示着自身的价值 ,这些人可谓中国最初的自由主义者 ,李伯元就是其中一个重要的代表。李伯元思想意识的演进过程 ,呈现出旧思想的蜕变、新思想的萌生和主导思想的成型三个阶段。通过对他独特的心路历程的揭示 ,可以为我们重新审视这位谴责小说大家的文学创作提供前提     

一类刚性常微分方程组初值问题中 Gear算法的应用

本文以Gear算法理论为基础,将其推广为适用于变维,初始值分段加入的 一类刚性常微分方程组的数值计算,并将其应用于有前置分流回路的线圈炮系统 方程.计算结果表明,Gear算法及其推广对此类刚性常微分方程组的计算是适宜 的与有效的.