Image‐Based Empirical Importance Sampling: An Efficient Way of Estimating Intensities

Abstract. Very recently, it has been suggested in the biomedical literature to combine computerized image analysis with non‐uniform sampling to increase the efficiency of estimators of intensities of biological cell populations. We give this ingenious idea of empirical importance sampling a stochastic formulation, using point process theory and modern sampling theory. We develop statistical tools for assessing its efficiency and construct optimal model‐based estimators of intensities. Examples of applications of empirical importance sampling in microscopy are provided.     

试论青藏高原普及九年制义务教育的重要性

为了贯彻党中央提出的“稳定、改革、发展”的战略方针,为了适应我国西部大开发的要求,本文从更深层次上认识青藏高原普及九年义务教育的重要性,对青藏高原地区社会的进步与发展具有重要的现实意义。     

The Gibbs sampler with particle efficient importance sampling for state-space models*

We consider Particle Gibbs (PG) for Bayesian analysis of non-linear non-Gaussian state-space models. As a Monte Carlo (MC) approximation of the Gibbs procedure, PG uses sequential MC (SMC) importance sampling inside the Gibbs to update the latent states. We propose to combine PG with the Particle Efficient Importance Sampling (PEIS). By using SMC sampling densities which are approximately globally fully adapted to the targeted density of the states, PEIS can substantially improve the simulation efficiency of the PG relative to existing PG implementations. The efficiency gains are illustrated in PG applications to a non-linear local-level model and stochastic volatility models.     

浅论讲政治的重要性与必要性

本文论述了我国大搞经济建设时期 ,为什么提倡党员领导干部一定要讲政治 ,阐释了政治与经济的关系 ,讲政治与国家前途命运的关系 ,以及对提高领导干部素质的重要意义。     

高校英语语音教学的探讨

语音教学已经成为高校外语教学中越来越受重视的对象,我们也越来越意识到语音教学是英语教学的重要内容之一。介绍了语音教学的重要性,语音教学的目的和教学重点以及语音教学所面临的种种困难。最后对高校语音教学提出了建议和展望。     

厚尾分布情形下的信用资产组合风险度量

本文研究风险因子多元厚尾分布情形下的信用资产组合风险度量问题.用多元t-Copula分布来描述标的资产收益率分布的厚尾性,同时将三步重要抽样技术发展到基多元t-Copula分布的资产组合模型中,拓宽和丰富了信用资产组合风险度量模型.同时,并运用了非线性优化技术中的Levenberg-Marquardt算法来解决重要抽样技术中风险因子期望向量估计.模拟结果表明该算法比普通Monte Carlo模拟法的计算效率更有效,且能很大程度上减少所要估计的损失概率的方差,从而更精确地估计出信用投资组合损失分布的尾部概率或给定置信度下组合VaR值.     

物业管理专业开设心理学课的必要性

随着房地产市场的发展 ,物业公司纷纷成立 ,随之而来的是物业管理专业人才的大量需求 ,为此 ,各高校陆续开设了物业管理专业。物业管理人才是复合型人才 ,需要跨学科跨专业的知识和能力 ,其中就包括心理学方面的知识和能力 ,尤其是管理心理学方面的知识和能力。所以 ,在物业管理专业课程中应增设心理学课 ,让学生掌握一定的心理学知识与技能 ,以适应社会需要。     

清末民国工商团体创建新式学堂的价值及意义

将所办学堂与所处环境的生产与生活密切联系，使工商团体的兴学活动与教育界呈现出不同的路径；同时，工商团体兴学对官方教育出现的弊端进行适当修正，并积极实践；借助各种机会工商团体将自己的经验及愿望反馈于教育决策部门，积极影响政府对教育的决策。近代工商团体参与新式学堂的创建，不仅推动了近代教育的发展，而且对近代中国经济乃至社会的早期现代化作出积极探索。     

A UNIFIED FRAMEWORK FOR MODELLING WILDLIFE POPULATION DYNAMICS†

This paper proposes a unified framework for defining and fitting stochastic, discrete‐time, discrete‐stage population dynamics models. The biological system is described by a state‐space model, where the true but unknown state of the population is modelled by a state process, and this is linked to survey data by an observation process. All sources of uncertainty in the inputs, including uncertainty about model specification, are readily incorporated. The paper shows how the state process can be represented as a generalization of the standard Leslie or Lefkovitch matrix. By dividing the state process into subprocesses, complex models can be constructed from manageable building blocks. The paper illustrates the approach with a model of the British grey seal metapopulation, using sequential importance sampling with kernel smoothing to fit the model.