Asymptotic properties of a generalized regression-type predictor of a finite population variance in probability sampling

A system of predictors for estimating a finite population variance is defined and shown to be asymptotically design-unbiased (ADU) and asymptotically design-consistent (ADC) under probability sampling. An asymptotic mean squared error (MSE) of a generalized regression-type predictor, generated from the system, is obtained. The suggested predictor attains the minimum expected variance of any design-unbiased estimator when the superpopulation model is correct. The generalized regression-type predictor and the predictor suggested by Mukhopadhyay (1990) are compared.     

"假象"背后的均衡及信息的代价研究

通过库诺特模型可以说明,“假象”的存在将改变均衡结果:如果信息获取是无成本的,那么“假象”将使信息占优一方的均衡利润增加,其对手的均衡利润可能减少,也可能增加;如果获取对手的信息是有代价的,根据我们给出的信息投资的边界条件,当获取信息的代价大于这一边界条件时,获取对手信息是有必要的,反之,应该放弃对信息的投资。     

Modeling the demand reduction input-output (I-O) inoperability due to terrorism of interconnected infrastructures.

Interdependency analysis in the context of this article is a process of assessing and managing risks inherent in a system of interconnected entities (e.g., infrastructures or industry sectors). Invoking the principles of input-output (I-O) and decomposition analysis, the article offers a framework for describing how terrorism-induced perturbations can propagate due to interconnectedness. Data published by the Bureau of Economic Analysis Division of the U.S. Department of Commerce is utilized to present applications to serve as test beds for the proposed framework. Specifically, a case study estimating the economic impact of airline demand perturbations to national-level U.S. sectors is made possible using I-O matrices. A ranking of the affected sectors according to their vulnerability to perturbations originating from a primary sector (e.g., air transportation) can serve as important input to risk management. For example, limited resources can be prioritized for the "top-n" sectors that are perceived to suffer the greatest economic losses due to terrorism. In addition, regional decomposition via location quotients enables the analysis of local-level terrorism events. The Regional I-O Multiplier System II (RIMS II) Division of the U.S. Department of Commerce is the agency responsible for releasing the regional multipliers for various geographical resolutions (economic areas, states, and counties). A regional-level case study demonstrates a process of estimating the economic impact of transportation-related scenarios on industry sectors within Economic Area 010 (the New York metropolitan region and vicinities).     

集团军山地进攻作战减员预计模型

收集了我军以往作战军减员的经验数据,建立军减员率的时间序列模型,提出计算机模拟的方法。在此基础上,着重分析影响减员的多种因素,对交战双方武器装备数量及技术等级,作战地区的地形和气候条件等因素进行了定量描述。运用专家咨询方法筛选了社会经济行为等"软"指标,用群体层次分析法确定各指标的权重,建立了量化指标体系,并运用该指标体系对我军今后主要作战对象进行了量化。结合以上因素对计算机模拟生成的数据进行修正,建立相应的调整算法。     

灰色动态预测模型在货币供应量预测中的应用

在对金融系统中货币供应量的预测进行相关研究的基础上,介绍了符合金融系统预测规律的灰色系统动态预测法,并根据中国货币供应量的实际数据进行了实证的预测检验。结果显示,这种方法简单,不需要借助于其他任何时间序列数据,需要数据量少,预测精确度高,对于近期预测尤其准确,也可进行中长期预测;实证预测结果也符合我国金融系统中货币供应量预测的实际。     

制约民间投资增长的问题及对策

我国投资运行的实践证明,民间投资在推动经济发展,促进产业结构调整,吸纳劳动力,缓解就业压力等方面,对国民经济和社会发展的作用非同一般。然而,由于投融资体制和政策环境的不完善,近年来民间投资的增长出现了一系列的结构失衡,投资增长速度相对趋缓。通过增强政府投资的"带动效应",加速金融创新,推广先进合理的融资模式等举措可以有效拉动民间投资的增长。     

金元之际诗人房皞探微

房是金末元初的重要诗人,"河汾诸老"之一。他追随元好问积极参与开创"以唐人为指归"的诗歌创作局面。史料散佚是其生平、思想、创作和地位长期以来隐而不显的主要原因。对有关史料的考稽辨析,对房文学思想、成就、贡献和地位的探赜发微,有助于从特定侧面揭示金末元初诗坛风尚和诗学思潮。     

商业银行对中小企业"惜贷"的原因及对策

我国商业银行在中小企业贷款问题上存在明显的"惜贷"倾向.其直接原因是中小企业普遍经济效益较差、信用不良、信息不透明,使银行无法保证预期收益.内部原因是两类激励相容问题,一是利率法定、企业缺乏抵押担保等客观因素所导致的商业银行与中小企业之间的激励不相容;二是内部制度不完善所导致的商业银行所有者与各级经营者之间的激励不相容.要从根本上解决这一难题,必须加快商业银行现代企业制度建设,推进信用担保资源社会化和利率自由化进程,同时也有待于中小企业整体经济效益的好转、社会信用及法制的完善和经济体制市场化改革的持续深入.     

打造我国“航母”级证券商的思路

我国的证券市场尽管只有12年的历史,其发展却极为迅速,但是,它仍未摆脱一些新兴市场的特点,突出表现为规模小、业务范围窄、抗风险能力差。我国证券商面临着极为严峻的内外竞争的压力。为此,我国证券商应当进行机构重组、资本重组、业务创新,打造我国自己的“航母”级证券商,应对面临的内忧外患。     

Marginal Means/Rates Models for Multiple Type Recurrent Event Data

Recurrent events are frequently observed in biomedical studies, and often more than one type of event is of interest. Follow-up time may be censored due to loss to follow-up or administrative censoring. We propose a class of semi-parametric marginal means/rates models, with a general relative risk form, for assessing the effect of covariates on the censored event processes of interest. We formulate estimating equations for the model parameters, and examine asymptotic properties of the parameter estimators. Finite sample properties of the regression coefficients are examined through simulations. The proposed methods are applied to a retrospective cohort study of risk factors for preschool asthma.