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151.
An economic two-stage screening procedure based on a dichotomous performance variable T and a continuous screening variable X is proposed. X is measured first to decide whether an item should be accepted, rejected, or additional observations should be taken. If no terminal decision is reached, T is then observed to classify the undecided items. Two models are considered; (i) the logistic model, where P(T = 1|X = x) is assumed to be a logistic function of x, and (ii) the normal model, where X given T is assumed to be normally distributed. A simple economic model based on inspection and misclassification costs is constructed. Optimal cutoff values on the screening variable are obtained by minimizing the expected cost subject to the constraint that the average outgoing quality attains a pre-specified level. Solutions are provided for both known-parameter and unknown-parameter cases. © 1995 John Wiley & Sons, Inc. 相似文献
152.
GM(1,1)模型与指数回归模型的比较与研究 总被引:3,自引:0,他引:3
GM(1,1)模型与指数回归模型都是对具有指数或近似指数规律的系列数据建立的数学模型。通过对两种模型进行比较与研究,发现一方面,利用数据列的灰指数特性建立指数回归模型,可以简单地实现数据列的预测过程;另一方面,利用指数回归模型可以对灰色理论的GM(1,1)模型进行控制和优化。 相似文献
153.
首先提出了视情工作间隔时间的确定方法,然后根据故障率的不同情况,分析了间隔时间的相应变化,最后进行了实际应用方面的讨论. 相似文献
154.
Fulfillment by Amazon versus fulfillment by seller: An interpretable risk-adjusted fulfillment model
With dual-channel choices, E-retailers fulfill their demands by either the inventory stored in third-party distribution centers, or by in-house inventory. In this article, using data from a wedding gown E-retailer in China, we analyze the differences between two fulfillment choices—fulfillment by Amazon (FBA) and fulfillment by seller (FBS). In particular, we want to understand the impact of FBA that will bring to sales and profit, compared to FBS, and how the impact is related to product features such as sizes and colors. We develop a risk-adjusted fulfillment model to address this problem, where the E-retailer's risk attitude to FBA is incorporated. We denote the profit gaps between FBA and FBS as the rewards for this E-retailer fulfilling products using FBA, our goal is to maximize the E-retailer's total rewards using predictive analytics. We adopt the generalized linear model to predict the expected rewards, while controlling for the variability of the reward distribution. We apply our model on a set of real data, and develop an explicit decision rule that can be easily implemented in practice. The numerical experiments show that our interpretable decision rule can improve the E-retailer's total rewards by more than 35%. 相似文献
155.
Economic screening procedures based on a continuous screening variable X in place of a dichotomous performance variable T are presented. Optimal critical values on the screening variable minimizing the expected cost are obtained for two models; it is assumed that X given T is normally distributed in normal model and P[T = 1|X] is a logistic function of X in the logistic model, and that costs are incurred by screening inspection and misclassification errors. Cases where some parameters are unknown are also considered. 相似文献
156.
本文论述了红军长征中左右两路军北上过程中的指挥系统、指挥班子、通讯系统、通讯队伍及其左右两路军的关系等重要问题。 相似文献
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随着武警部队三级综合通信网络的不断完善和功能拓展,基层执勤部队信息化人才的选拔培养和使用管理效益,已成为影响和制约信息化平台功能有效发挥的重要因素。 相似文献
160.