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151.
在劳动力密集的河南省,大量输出劳动力可以迅速促进当地经济的发展和人民生活水平的提高,但人们往往忽视从长远看过量输出导致的非均衡流动却可能束缚输出地经济的发展,笔者通过对河南省信阳市固始县为期13天的调研,对这一问题进行了研究。本文描述了劳动力的大量输出对当地经济发展的促进,着重分析了当地劳动力流动的原因,并分析了非均衡流动给当地经济未来发展带来的三个问题。文章将在前半部分从劳动力流动的环境动力和劳动力流动去向的角度,结合劳动力流动的相关理论,对谷围村劳动力流动情况进行分析,并用"吸出模型"解释劳动力非均衡流动带来的问题和产生的原因。文章后半部分从劳动力大量输出对当地县域经济影响的角度分析了在劳动力密集的固始县企业招工难且劳动力成本高于外地的奇怪现象。最后,文章对固始县为实现劳动力均衡流动而采取的措施进行了研究,总结出劳动力过量输出地区的经济发展模式即"固始模式",并对该模式进行了分析。 相似文献
152.
In event time data analysis, comparisons between distributions are made by the logrank test. When the data appear to contain crossing hazards phenomena, nonparametric weighted logrank statistics are usually suggested to accommodate different-weighted functions to increase the power. However, the gain in power by imposing different weights has its limits since differences before and after the crossing point may balance each other out. In contrast to the weighted logrank tests, we propose a score-type statistic based on the semiparametric-, heteroscedastic-hazards regression model of Hsieh [2001. On heteroscedastic hazards regression models: theory and application. J. Roy. Statist. Soc. Ser. B 63, 63–79.], by which the nonproportionality is explicitly modeled. Our score test is based on estimating functions derived from partial likelihood under the heteroscedastic model considered herein. Simulation results show the benefit of modeling the heteroscedasticity and power of the proposed test to two classes of weighted logrank tests (including Fleming–Harrington's test and Moreau's locally most powerful test), a Renyi-type test, and the Breslow's test for acceleration. We also demonstrate the application of this test by analyzing actual data in clinical trials. 相似文献
153.
THOMAS RICHARDSON 《Scandinavian Journal of Statistics》2003,30(1):145-157
We consider acyclic directed mixed graphs, in which directed edges ( x → y ) and bi-directed edges ( x ↔ y ) may occur. A simple extension of Pearl's d -separation criterion, called m -separation, is applied to these graphs. We introduce a local Markov property which is equivalent to the global property resulting from the m -separation criterion for arbitrary distributions. 相似文献
154.
Malka Gorfine Li Hsu Ross L. Prentice 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2003,65(3):643-661
Summary. In many biomedical studies, covariates are subject to measurement error. Although it is well known that the regression coefficients estimators can be substantially biased if the measurement error is not accommodated, there has been little study of the effect of covariate measurement error on the estimation of the dependence between bivariate failure times. We show that the dependence parameter estimator in the Clayton–Oakes model can be considerably biased if the measurement error in the covariate is not accommodated. In contrast with the typical bias towards the null for marginal regression coefficients, the dependence parameter can be biased in either direction. We introduce a bias reduction technique for the bivariate survival function in copula models while assuming an additive measurement error model and replicated measurement for the covariates, and we study the large and small sample properties of the dependence parameter estimator proposed. 相似文献
155.
The ability to infer parameters of gene regulatory networks is emerging as a key problem in systems biology. The biochemical
data are intrinsically stochastic and tend to be observed by means of discrete-time sampling systems, which are often limited
in their completeness. In this paper we explore how to make Bayesian inference for the kinetic rate constants of regulatory
networks, using the stochastic kinetic Lotka-Volterra system as a model. This simple model describes behaviour typical of
many biochemical networks which exhibit auto-regulatory behaviour. Various MCMC algorithms are described and their performance
evaluated in several data-poor scenarios. An algorithm based on an approximating process is shown to be particularly efficient. 相似文献
156.
余德才 《河北建筑科技学院学报(社会科学版)》2008,(3):64-67
遵循整体观和相对性理念,在“认知思维模式”基础上,提出了一种无学科界面、自然融合型的科学与人文整合模式,从根本上解决了科学与人文长期以来的分割与对立的局面。并依据该模式提出了“‘组织结构’决定‘性能'”法则、“更大层次系统对系统制约的第一性”的“伦理”法则、“子系统之间和谐共存”法则等思想将引导人类走上“天人合一”的和谐永续的文明道路。 相似文献
157.
The elimination or knockout format is one of the most common designs for pairing competitors in tournaments and leagues. In each round of a knockout tournament, the losers are eliminated while the winners advance to the next round. Typically, the goal of such a design is to identify the overall best player. Using a common probability model for expressing relative player strengths, we develop an adaptive approach to pairing players each round in which the probability that the best player advances to the next round is maximized. We evaluate our method using simulated game outcomes under several data-generating mechanisms, and compare it to random pairings, to the standard knockout format, and to two variants of the standard format. 相似文献
158.
王鸿鸣 《山东科技大学学报(社会科学版)》2008,10(4):41-45
有关人权限制的问题,我国宪法不论是文本还是理念,都与国际人权公约存在差异,因而产生两者之间的冲突和协调问题。我国宪法限权条款有待明确化、具体化,违宪审查制度有待建立。 相似文献
159.
Internet环境下的网络教学 总被引:1,自引:0,他引:1
Internet环境下的网络教学已成为人类进行终身教育和创新教育的最佳平台。文章着重论述了Internet环境下的多模式教学———讲授模式、个别辅导模式、讨论学习模式、探索学习模式、协作学习模式 相似文献
160.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations. 相似文献