Robust bootstrap estimates in heteroscedastic semi-varying coefficient models and applications in analyzing Australia CPI data

This article deals with the estimation of the parametric component, which is of primary interest, in the heteroscedastic semi-varying coefficient models. Based on the bootstrap technique, we present a procedure for estimating the parameters, which can provide a reliable approximation to the asymptotic distribution of the profile least-square (PLS) estimator. Furthermore, a bootstrap-type estimator of covariance matrix is developed, which is proved to be a consistent estimator of the covariance matrix. Moreover, some simulation experiments are conducted to evaluate the finite sample performance for the proposed methodology. Finally, the Australia CPI dataset is analyzed to demonstrate the application of the methods.     

空气中多种醛酮液相色谱法侧定的研究

本文研究了空气中多种醛酮的测定。目前国内仅对空气中甲醛的测定研究较多,国外报导的方法需用萃取、浓缩等一系列前处理过程,方法麻烦,易引入杂质造成污染。本文报导的方法系采用2.4—二硝基苯肼的甲醇强酸溶液吸收空气中醛酮直接注入液相色谱仪中进行分离测定。研究表明:本法分离效果好,重复性好,方法简便,速度快,测定的精密度和准确度符合微量分析误差的要求。     

Bayesian bridge-randomized penalized quantile regression estimation for linear regression model with AP(q) perturbation

Bridge penalized regression has many desirable statistical properties such as unbiasedness, sparseness as well as ‘oracle’. In Bayesian framework, bridge regularized penalty can be implemented based on generalized Gaussian distribution (GGD) prior. In this paper, we incorporate Bayesian bridge-randomized penalty and its adaptive version into the quantile regression (QR) models with autoregressive perturbations to conduct Bayesian penalization estimation. Employing the working likelihood of the asymmetric Laplace distribution (ALD) perturbations, the Bayesian joint hierarchical models are established. Based on the mixture representations of the ALD and generalized Gaussian distribution (GGD) priors of coefficients, the hybrid algorithms based on Gibbs sampler and Metropolis-Hasting sampler are provided to conduct fully Bayesian posterior estimation. Finally, the proposed Bayesian procedures are illustrated by some simulation examples and applied to a real data application of the electricity consumption.     

基于统计检验的企业生命周期判定方法比较

文章选取32家中国上市汽车企业作为研究对象,分别用综合指标法和主成分分析法对企业所处生命周期进行判定,再利用Wilcoxon符号秩检验和kappa—致性检验对两种判定结果进行检验对比,从而得出结论:综合指标法和主成分分析法均科学有效,但在具体应用时各有所长.Wilcoxon符号秩检验和kappa—致性检验叠加运用效果较好,且检验结果具有一致性.     

A new confidence interval in errors-in-variables model with known error variance

This paper considers constructing a new confidence interval for the slope parameter in the structural errors-in-variables model with known error variance associated with the regressors. Existing confidence intervals are so severely affected by Gleser–Hwang effect that they are subject to have poor empirical coverage probabilities and unsatisfactory lengths. Moreover, these problems get worse with decreasing reliability ratio which also result in more frequent absence of some existing intervals. To ease these issues, this paper presents a fiducial generalized confidence interval which maintains the correct asymptotic coverage. Simulation results show that this fiducial interval is slightly conservative while often having average length comparable or shorter than the other methods. Finally, we illustrate these confidence intervals with two real data examples, and in the second example some existing intervals do not exist.     

Diagnostics for quasi-likelihood nonlinear models

Quasi-likelihood nonlinear models (QLNMs) are an extension of generalized linear model and include a widen class of models as special cases. This article investigates some diagnostic methods in QLNMs. An equivalency between a case-deletion model and a mean-shift outlier model in QLNM is established. Two simulation study and a real dataset are used to illustrate the proposed diagnostic methods.     

高速铁路桩板结构承载板伸缩温度力研究

以某高速铁路桩板结构路基工程为背景，研究了桩板结构路基单联跨数对承载板体伸缩温度应力的影响规律，提出了桩板结构的结构布置原则；并根据桩板结构路基具体结构特征，推导了计算结构整体升降温引起的承载板体伸缩温度应力计算公式，该解析式与空间有限元法计算结果较好吻合，可方便地计算承载板的伸缩温度应力。     

A dynamic product quality evaluation based pricing model for perishable food supply chains

Waste stemmed from inappropriate quality control and excessive inventories is a major challenge for perishable food management in grocery retail chains. Improvement of visibility and traceability in food supply chains facilitated by tracking and tracing technologies has great potential to improve operations efficiency. This research aims to reduce food spoilage waste and maximise food retailer's profit through a pricing approach based on dynamically identified food shelf life. The proposed model is evaluated through different pricing policies to exploit the benefits from utilising accurate product shelf life information captured through innovated tracking and monitoring technologies. Numerical analysis is conducted in an illustrative case study.     

食品全产业链三维风险评价

为了有效控制食品全产业链风险,降低食品安全事件发生概率和影响程度,文章运用三维风险分析模型构建食品全产业链风险评价模型.从全产业链流程视角分析食品全产业链的各环节风险,从而构建食品全产业链风险评价指标体系.然后,采用熵值法确定食品全产业链风险评价指标重要度,结合现有食品全产业链风险发生可能性统计资料和风险后果划分标准,确定食品全产业链的各环节风险影响因素风险程度.根据风险发生概率、风险指标重要度和风险因素发生后果三维风险评价模型确定的关键因素,寻求相应的食品安全风险控制措施.     

Depletion Effect of Work-Leisure Conflict: A Daily Diary Study

The negative effect of work-leisure conflict has attracted the attention of researchers. However, no previous research has determined the relationship between work-leisure conflict and ego depletion. Therefore, this study explores the relationship between daily work-leisure conflict and ego depletion, as well as the role of individuals’ negative emotions and core self-evaluations in this process based on ego depletion theory. Through the method of daily diary research, 77 employees were tracked for 7 consecutive work days. The results show that work-leisure conflict is positively related to employee ego depletion, that the negative emotions play a mediating role in this relationship and that core self-evaluations moderate the indirect effect of work-leisure conflict on ego depletion through negative emotions. In this study, daily diary method is used to verify the dynamic characteristics of work-leisure conflict, negative emotions and ego depletion, and some new insights into how to reduce employee ego depletion are provided.