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1.
伊尹作为中国历史上第一位贤相,其突出的个人素质表现在精于至味之理、精通耕作之道、创制治病汤液几方面,即懂得如何吃饭、种地和治病。这正是广大民众最为关心的事情,也是治理内政极其关键的因素,只有这三件事做得好,才可能完成"祀与戎"等国家大事。如此全面素质的形成,与其丰富的人生经历和勤于思索有关。  相似文献   
2.
系统总结了在伸展构造背景下,导致反映构造特征的地层倾角模式复杂化的多种因素。沉积相的不同、岩性变化、井眼状况和测井作业时间等多种因素都可能使地层倾角资料复杂化。进一步指出在拉张盆地中,进行倾角资料的构造解释,必须了解其构造样式的多样性和复杂性,解释存在的多解性。重点解剖了铲式断层在横剖面情况下,对于不同构造位置下的倾角模式。详细分析了一个倾角模式对应多种构造样式的倾角构造解释实例。倾角资料的构造解释应是综合解释,既要综合井筒的相关地质资料,又要综合测井与地质知识,还必须考虑综合地震资料。  相似文献   
3.
商业银行个人金融服务的国际比较   总被引:1,自引:0,他引:1  
目前,我国商业银行以代发工资、代收费等业务为突破口,已开发了近40个品种的个人金融服务业务。谁能提供更快捷、方便的金融服务,谁就会拥有更多的客户。进一步的对外开放,个人金融服务的巨大市场是中外银行竞争的焦点。个人金融服务市场从以往简单地通过银行储蓄存款获得利息并保障安全,已跳跃到支付结算、外汇买卖、临时透支、贷款融资、经营投资和综合理财等全方位、多层次的服务。这些对国内各家商业银行拓展个人金融服务提出了巨大的机遇和挑战。  相似文献   
4.
提出了一种基于小波变换的管理数据处理方法,把公司管理上的数据看成一个非平稳的时间序列,利用小渡函数将该时间序列分解到不同的频率通道上,然后将分解后的信号当作近似的平稳时间序列,用一些传统的统计方法进行预测,同时对中国足球彩票若干期的销售量数据进行了处理和预测,并将结果与实际销量以及用传统的AR模型的预测值进行了比较。  相似文献   
5.
档案信息利用服务网络化现状的思考   总被引:1,自引:0,他引:1  
在社会信息化的趋势下,档案信息化已被高度关注。档案信息利用服务网络化是新形势下档案利用的一种新方式。由于诸多因素的制约,使得基于Internet平台的B S模式的网络利用服务明显滞后。本文从档案信息利用服务网络化的现状、产生的原因及对策三个方面做出分析。  相似文献   
6.
Olive Oil Consumption in Greece: A Microeconometric Analysis   总被引:2,自引:1,他引:1  
In this paper, the factors affecting at-home demand for three types of oils and fats in Greece, with emphasis on olive oil, are investigated using the linear approximation of the Almost Ideal Demand System and family budget survey data. To overcome the econometric problem created with the existence of zero expenditure, a generalization of the two-stage Heckman procedure is employed. In order to investigate the role of self-consumption, two different samples were used. The first includes all households; the second excludes those that acquire olive oil only from own production. According to the results, there are important differences in the first stage of the decision process between the two samples. Unlike the first stage, the second stage of the decision process found no important differences between the results for the two samples.  相似文献   
7.
The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SEΔ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SEΔ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SEΔ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
8.
A test of congruence among distance matrices is described. It tests the hypothesis that several matrices, containing different types of variables about the same objects, are congruent with one another, so they can be used jointly in statistical analysis. Raw data tables are turned into similarity or distance matrices prior to testing; they can then be compared to data that naturally come in the form of distance matrices. The proposed test can be seen as a generalization of the Mantel test of matrix correspondence to any number of distance matrices. This paper shows that the new test has the correct rate of Type I error and good power. Power increases as the number of objects and the number of congruent data matrices increase; power is higher when the total number of matrices in the study is smaller. To illustrate the method, the proposed test is used to test the hypothesis that matrices representing different types of organoleptic variables (colour, nose, body, palate and finish) in single‐malt Scotch whiskies are congruent.  相似文献   
9.
Maximum likelihood estimation and goodness-of-fit techniques are used within a competing risks framework to obtain maximum likelihood estimates of hazard, density, and survivor functions for randomly right-censored variables. Goodness-of- fit techniques are used to fit distributions to the crude lifetimes, which are used to obtain an estimate of the hazard function, which, in turn, is used to construct the survivor and density functions of the net lifetime of the variable of interest. If only one of the crude lifetimes can be adequately characterized by a parametric model, then semi-parametric estimates may be obtained using a maximum likelihood estimate of one crude lifetime and the empirical distribution function of the other. Simulation studies show that the survivor function estimates from crude lifetimes compare favourably with those given by the product-limit estimator when crude lifetimes are chosen correctly. Other advantages are discussed.  相似文献   
10.
Summary.  As a part of the EUREDIT project new methods to detect multivariate outliers in incomplete survey data have been developed. These methods are the first to work with sampling weights and to be able to cope with missing values. Two of these methods are presented here. The epidemic algorithm simulates the propagation of a disease through a population and uses extreme infection times to find outlying observations. Transformed rank correlations are robust estimates of the centre and the scatter of the data. They use a geometric transformation that is based on the rank correlation matrix. The estimates are used to define a Mahalanobis distance that reveals outliers. The two methods are applied to a small data set and to one of the evaluation data sets of the EUREDIT project.  相似文献   
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