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1.
The aim of this paper is to measure the effects on household composition of changes in demographic events, e.g. mortality, fertility, marriage, divorce. British household data are taken from the General Household Survey and aged by simulation to 2001 using a ‘Most Likely’ model. Subsequently different assumptions of each demographic event are taken from 1991 so that the effects of perturbations within each event can be studied. Special features of the simulation model are the differentiations between cohabitation and marriage and separation and divorce, and the detailed breakdowns of household types such as lone parents into single and previously married women and men with children aged 0–4, 5–15 and 16 and over.  相似文献   
2.
本文提出了圆锥轴受扭时静、动力的传递矩阵。该方法简便实用,适于工程技术人员在微机上应用。  相似文献   
3.
Huber's estimator has had a long lasting impact, particularly on robust statistics. It is well known that under certain conditions, Huber's estimator is asymptotically minimax. A moderate generalization in rederiving Huber's estimator shows that Huber's estimator is not the only choice. We develop an alternative asymptotic minimax estimator and name it regression with stochastically bounded noise (RSBN). Simulations demonstrate that RSBN is slightly better in performance, although it is unclear how to justify such an improvement theoretically. We propose two numerical solutions: an iterative numerical solution, which is extremely easy to implement and is based on the proximal point method; and a solution by applying state-of-the-art nonlinear optimization software packages, e.g., SNOPT. Contribution: the generalization of the variational approach is interesting and should be useful in deriving other asymptotic minimax estimators in other problems.  相似文献   
4.
发展可再生能源对保障能源安全、调整能源结构、保护生态环境、实现可持续发展具有重大意义。但我国在发展可再生能源过程中还存在着认识不足、成本太高、技术水平较低、市场不稳定和政策法律体系不完善等诸多障碍。本文对这些障碍进行了具体分析,并有针对性地提出了相应的政策建议。  相似文献   
5.
As we recognize how taxing our profession can be, therapist's self‐care has become a salient topic in mental health. However, we are still discerning how to promote self‐care in our practice and in training. In this paper, we present a study on the personal gains that MFT students experienced after participating in the Person‐of‐the‐Therapist Training (POTT). We propose that the reported changes (better understanding of self, change to self, relational changes, and change as a process) constitute improvements in the trainees’ well‐being, and can therefore be considered self‐caring behaviors and practices. We state that models like POTT, that focus on embracing our vulnerability, can help clinicians be more caring toward ourselves. We conclude this paper by presenting clinical and training recommendations.  相似文献   
6.
对于马基雅维里,评论家们往往忽视了其复杂性.在马基雅维里的思想中,道德和政治存在着明显的差异,我们称之为"道德-政治"的二元对立.我们可以发现这种二元对立是基于现实主义的考虑.马基雅维里既如同前期人文主义者,在<君主论>中大谈君主的美德;但是同时又宣称君主可以为了目的而不择手段,这正是他与前期人文主义者的最大相异之处.马基雅维里也因此陷入了"道德-政治"的二元对立之中.马基雅维里的这种二元对立,也给予了我们一种多元的启示.  相似文献   
7.
The additive hazards model is one of the most commonly used regression models in the analysis of failure time data and many methods have been developed for its inference in various situations. However, no established estimation procedure exists when there are covariates with missing values and the observed responses are interval-censored; both types of complications arise in various settings including demographic, epidemiological, financial, medical and sociological studies. To address this deficiency, we propose several inverse probability weight-based and reweighting-based estimation procedures for the situation where covariate values are missing at random. The resulting estimators of regression model parameters are shown to be consistent and asymptotically normal. The numerical results that we report from a simulation study suggest that the proposed methods work well in practical situations. An application to a childhood cancer survival study is provided. The Canadian Journal of Statistics 48: 499–517; 2020 © 2020 Statistical Society of Canada  相似文献   
8.
In this study, we propose a prior on restricted Vector Autoregressive (VAR) models. The prior setting permits efficient Markov Chain Monte Carlo (MCMC) sampling from the posterior of the VAR parameters and estimation of the Bayes factor. Numerical simulations show that when the sample size is small, the Bayes factor is more effective in selecting the correct model than the commonly used Schwarz criterion. We conduct Bayesian hypothesis testing of VAR models on the macroeconomic, state-, and sector-specific effects of employment growth.  相似文献   
9.
Lin  Tsung I.  Lee  Jack C.  Ni  Huey F. 《Statistics and Computing》2004,14(2):119-130
A finite mixture model using the multivariate t distribution has been shown as a robust extension of normal mixtures. In this paper, we present a Bayesian approach for inference about parameters of t-mixture models. The specifications of prior distributions are weakly informative to avoid causing nonintegrable posterior distributions. We present two efficient EM-type algorithms for computing the joint posterior mode with the observed data and an incomplete future vector as the sample. Markov chain Monte Carlo sampling schemes are also developed to obtain the target posterior distribution of parameters. The advantages of Bayesian approach over the maximum likelihood method are demonstrated via a set of real data.  相似文献   
10.
石板坡大桥主跨由钢箱梁与预应力混凝土箱梁组成。针对该桥钢箱梁桥面板局部受力复杂的情况,运用ANSYS软件建立了钢箱梁结构分析的空间有限元模型,分析了钢箱梁在车载作用下局部应力的分布特点。  相似文献   
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