失业与就业:一个世界性的难题

在世界经济日益一体化的今天,综观全球,人们会惊奇地发现,失业———这一伴随资本主义生产方式和市场经济的产生而出现的社会现象,已经成为一个困扰许多国家经济和社会发展的严重问题。从西欧到东欧,从北美到南美,从发达国家到发展中国家,失业与就业成为人们关注的焦点,“创造就业机会”、“制定反失业对策”成为各国经济政策的首要目标。可以毫不夸张地说,当今世界几乎所有的国家,都不得不面对失业与就业这一世界性的难题。本文试图从宏观的角度,对世界各国不同类型的失业,以及主要资本主义国家治理失业与贫困问题的社会政策,进行分析与考察,从中总结出一些带有普遍性规律性的问题,为我国实施再就业工程提供决策思路和有益借鉴     

正确认识和大力发展个体私营经济

改革开放以来,个体私营经济从计划经济坚硬的土地上崭露头角,显示了较强的生命力。文章试从个体私营经济存在和发展的必然性及其曲折的发展过程入手,论述了其在国民经济发展中的作用,并提出个体私营等非公有制经济发展中存在的主要问题及对策     

盐度对尖鳍鲤(Cyprinus acutidorsalis)早期发育的影响

尖鳍鲤是一种能长期适应咸淡水生活的鲤科鱼类, 其受精、孵化可在０ ～１２５ ‰盐度范围内进行, 最适盐度为２５ ‰～７５ ‰; 卵黄囊仔鱼能适应１５０ ‰的盐度, 适宜的盐度是２５ ‰～７５ ‰; 在７５ ‰的盐度下生长最好, 存活率最高, 卵黄的吸收最快; 经每级２５ ‰的盐度梯度（ 范围０ ～３０ ‰） 驯化一周, 尖鳍鲤仔鱼最高能适应２５０ ‰的盐度, 比野鲤适应盐度的范围高（ 野鲤仔鱼最高为６０ ‰）     

我国消费、投资、净出口与经济增长

 消费、投资与出口通常并称为拉动经济增长的三驾马车,对经济增长产生重要作用。同时,经济增长也影响着它们的规模。针对这种情况,本文通过建立联立方程模型以及脉冲响应函数,对我国经济1978-2006年的历史数据进行实证分析,揭示我国改革开放以来它们之间的关系。     

Analysis of microtubule dynamics using growth curve models

Microtubules are part of the structural network within a cell's cytoplasm, providing structural support as well as taking part in many of the cellular processes. A large body of data provide evidence that dynamics of microtubules in a cell is reponsible for the performance of many critical cellular functions such as cell division. In this article, we study the effect of four different isoforms of a protein tau on microtubule dynamics using growth curve models. The results show that a linear growth curve model is sufficient to explain the data. Moreover, we find that a mutated version of a 3-repeat tau protein has a similar effect as a 4-repeat tau protein on microtubule dynamics. The latter findings conform with the biological understanding of the effect of the protein tau on microtubule dynamics.     

Large sample estimation and prediction for explosive growth curve models

Asymptotic distributions of maximum likelihood estimators for the parameters in explosive growth curve models are derived. Limit distributions of prediction errors when the parameters are estimated are also obtained. The growth curve models are viewed as multivariate time-series models, and the usual time-series methods are used for prediction. Estimation constrained by a hypothesis of homogeneity of growth rates is also considered.     

Considerations for optimal nonparametric regression under a generalizederror structure

Nonparametric smoothing, such as kernel or spline estimation, has been examined extensively under the assumption of uncorrelated errors. This paper addresses the effects of potential correlation on consistency and other asymptotic properties in a repeated-measures model, using directly optimized linear smoothers of the replicate means. Unrestricted optimal weights, with respect to squared error loss, are used to confirm a lack of consistency for all linear estimators in an autocorrelated errors model. The results indicate kernel methods that work well for an uncorrelated errors model may not have the ability to perform satisfactorily when correlation is introduced, due to an asymmetry in the optimal weights, which disappears for an uncorrelated errors model. These would include data-driven bandwidth selection methods, adjustments of the bandwidth to accommodate correlation, higher-order kernels, and related bias reduction techniques. The analytic results suggest alternative approaches, not considered here in detail, which have shown merit.     

Classification procedures using principal component analysis and stepwise discriminant function

Classification procedures are examined in the case when the dimensionality exceeds the sample size. Two particular suggestions are (i) Principal components analysis and (ii) Two-step discriminant analysis. Comparisons are made in the two sample and the several sample cases. Extensions to growth curve model are investigated using the two stage discriminant analysis.     

四川民族地区经济发展与社会稳定战略的实现途径

民族地区的社会稳定与经济发展息息相关。区域资源综合开发和整体开发资源是经济发展和社会稳定的血脉和基础,因此民族地区要要立足特色优势资源,全面落实科学发展观,加强资源整合与综合利用,发展资源节约型和环境友好型产业,构建特色优势产业体系,才能最终促进四川民族地区经济与社会的可持续发展。“十二五”期间,四川民族地区将进入经济发展与社会稳定的重要阶段,本文从加强民族地区整合优势资源,构建优势产业体系出发,阐述了推进传统特色农牧业向现代特色农牧业跨越,以及维护社会稳定的具体措施。