带常数项的最优加权组合预测

We propose a model based on the optimal weighted combinational forecasting with constant terms,give formulae of the weights and the average errors as well as a rela- tion of the model and the corresponding model without constant terms,and compare these models.Finally an example was given,which showed that the fitting precision has been enhanced.     

Forecasting daily supermarket sales using exponentially weighted quantile regression

Inventory control systems typically require the frequent updating of forecasts for many different products. In addition to point predictions, interval forecasts are needed to set appropriate levels of safety stock. The series considered in this paper are characterised by high volatility and skewness, which are both time-varying. These features motivate the consideration of forecasting methods that are robust with regard to distributional assumptions. The widespread use of exponential smoothing for point forecasting in inventory control motivates the development of the approach for interval forecasting. In this paper, we construct interval forecasts from quantile predictions generated using exponentially weighted quantile regression. The approach amounts to exponential smoothing of the cumulative distribution function, and can be viewed as an extension of generalised exponential smoothing to quantile forecasting. Empirical results are encouraging, with improvements over traditional methods being particularly apparent when the approach is used as the basis for robust point forecasting.     

A RAPID APPROXIMATION FOR PREDICTING THE HYDROCARBON DISCOVERY RATE: PART 2. IMPROVING THE ACCURACY

In Part 1 of this paper, we noted the systematic errors in the estimates of means and standard deviations produced by a rapid approximation applied to a model of hydrocarbon discovery. In Part 2, we apply regression to predict the approximation errors, as functions of model parameters and approximation output. With the regression model, we can correct much of the error in the approximation, as we illustrate with data from the Nisku-Shelf play of western Canada.     

医院医疗服务质量管理的灰关联分析

将灰关联分析方法应用于医院管理年活动中,分析了影响医疗服务质量的相关因素,并对医院医疗服务质量进行综合评价.     

W-Mo系复合材料的制备及其特性波阻抗

 采用放电等离子烧结技术，在相同的温度（1 473 K）及压力（30 MPa）下，制备出不同配比的致密的W-Mo系复合材料样品。采用高精度超声波脉冲回波重合方法，精确测量了超声波在样品中传播的横、纵波声速，并由此得到样品的特性波阻抗值。对样品的相组成分析及电子探针分析的结果表明，W-Mo系复合材料主要是以W、Mo机械混合的形式通过粘结相获得致密化的。因此，选用混合物模型对其特性波阻抗值进行了理论预测，与实测值的比较表明该模型能对W-Mo系复合材料的特性波阻抗作出比较准确的预测。     

应用线性回归方法对无形资产进行收益预测

无形资产评估对引导列形资产的建立和完善具有重要作用，收益法是常用的无形资产评估方法，而收益的预测是无形资产评估中的一个难题，本文以新疆某上市公司为例，尝试在无形资产评估方法中用多元线性回归进行收益预测。     

区域科技创新能力的灰色关联综合评价研究

采用灰色关联度确定权重的多目标决策方法,根据科技创新能力相关的数据指标集,对我国八大经济区科技创新能力给予了综合评价和排序.这种定量确定权重的方法,为综合评价区域的创新能力提供了一种更为实用、简洁、可操作性的新方法.     

基于预测有效度的组合预测方法冗余信息的判定

基于预测方法有效度的概念 ,建立了考虑预测精度标准差的预测有效度的组合模型 ,提出了几个新的概念 ,给出冗余信息出现的两个判定定理 .并用实例说明判定定理的有效性 .     

基于对数灰关联度的加权几何平均组合预测模型的有效性

基于对数灰关联度的加权几何平均组合预测是一种新的非线性组合预测。针对该方法提出新的优性组合预测、预测方法优超、冗余度等概念,给出优性组合预测存在的充分条件,最后证明冗余预测方法的一个判定定理。     

关联分析理论在航空维修工程中的应用

文章利用灰色系统理论的关联度分析法较好地解决了航空维修质量评价这个问题。通过举例分析，证明了这种分析方法的可行性