Varying-coefficient single-index measurement error model

This paper proposes a varying-coefficient single-index measurement error model, which consists of measurement error in the index covariates. We combine the simulation-extrapolation technique, the local linear regression and the weighted least-squares method to estimate the unknowns of the current model, and develop the asymptotic properties of the resulting estimators under some conditions. A simulation study is conducted to evaluate the proposed methodology, and a real example is also studied to illustrate our given methodology.     

A comparison of alternative methods to construct confidence intervals for the estimate of a break date in linear regression models

This article considers constructing confidence intervals for the date of a structural break in linear regression models. Using extensive simulations, we compare the performance of various procedures in terms of exact coverage rates and lengths of the confidence intervals. These include the procedures of Bai (1997 Bai, J. (1997). Estimation of a change point in multiple regressions. Review of Economics and Statistics 79:551–563.[Crossref], [Web of Science ®] , [Google Scholar]) based on the asymptotic distribution under a shrinking shift framework, Elliott and Müller (2007 Elliott, G., Müller, U. (2007). Confidence sets for the date of a single break in linear time series regressions. Journal of Econometrics 141:1196–1218.[Crossref], [Web of Science ®] , [Google Scholar]) based on inverting a test locally invariant to the magnitude of break, Eo and Morley (2015 Eo, Y., Morley, J. (2015). Likelihood-ratio-based confidence sets for the timing of structural breaks. Quantitative Economics 6:463–497.[Crossref], [Web of Science ®] , [Google Scholar]) based on inverting a likelihood ratio test, and various bootstrap procedures. On the basis of achieving an exact coverage rate that is closest to the nominal level, Elliott and Müller's (2007 Elliott, G., Müller, U. (2007). Confidence sets for the date of a single break in linear time series regressions. Journal of Econometrics 141:1196–1218.[Crossref], [Web of Science ®] , [Google Scholar]) approach is by far the best one. However, this comes with a very high cost in terms of the length of the confidence intervals. When the errors are serially correlated and dealing with a change in intercept or a change in the coefficient of a stationary regressor with a high signal-to-noise ratio, the length of the confidence interval increases and approaches the whole sample as the magnitude of the change increases. The same problem occurs in models with a lagged dependent variable, a common case in practice. This drawback is not present for the other methods, which have similar properties. Theoretical results are provided to explain the drawbacks of Elliott and Müller's (2007 Elliott, G., Müller, U. (2007). Confidence sets for the date of a single break in linear time series regressions. Journal of Econometrics 141:1196–1218.[Crossref], [Web of Science ®] , [Google Scholar]) method.     

A new policy for designing acceptance sampling plan based on Bayesian inference in the presence of inspection errors

The purpose of this article is to present a new policy for designing an acceptance sampling plan based on the minimum proportion of the lot that should be inspected in the presence of inspection errors. It is assumed that inspection is not perfect and every defective item cannot be detected with complete certainty. The Bayesian method is used for obtaining the probability distribution function of the number of defective items in the lot. To design this model, two constraints of producer risk and consumer risk are considered during the inspection process by using two specified points on operating characteristic curve. In order to illustrate the application of the proposed model, an example is presented. In addition, a sensitivity analysis is performed to analyze the model performance under different scenarios of process parameters and the results are elaborated. Finally, the efficiency of the proposed model is compared with the sampling method of Spencer and Kevan de Lopez (2017) at the same conditions.     

公共决策失误的界定及表现

公共决策失误是指公共决策主体在处理公共事务、实行公共管理的过程中,由于主体或情境因素的影响导致决策不当,给公共利益造成损失或造成其他不良后果的决策行为.评判公共决策失误既要进行理论评判,又要进行效果评估,还要考虑决策成本.决策失误的表现形式有决策错误、决策失效与决策和机会失误.     

基于离差最大化的组合评价方法研究

本文提出了一种基于离差最大化的组合评价方法,该方法首先利用多个单一评价方法对决策对象评价值之间的总离差达到最大的思想将各单一的评价值组合起来,得到各决策方案的组合评价结果并对其进行排序;其次,设计并采用组合误差平方和对组合评价的效果进行度量。最后结合实例,将本文提出的组合评价方法与平均值组合法、模糊Borda组合法进行对比分析,结果表明该组合评价方法的组合误差更小,有效性更强。     

Heteroskedasticity‐Robust Standard Errors for Fixed Effects Panel Data Regression

The conventional heteroskedasticity‐robust (HR) variance matrix estimator for cross‐sectional regression (with or without a degrees‐of‐freedom adjustment), applied to the fixed‐effects estimator for panel data with serially uncorrelated errors, is inconsistent if the number of time periods T is fixed (and greater than 2) as the number of entities n increases. We provide a bias‐adjusted HR estimator that is ‐consistent under any sequences (n, T) in which n and/or T increase to ∞. This estimator can be extended to handle serial correlation of fixed order.     

音误现象的学理分析

从方言到外语、从古音到今音相互印证,通过个案,对音误进行描写,并作出学理上的分析.描写的是音误背后的动因,分析的是音误存在的合理性,但在有些情况下,规定应大于描写.     

交织和BCH编码对蓝牙2.0数据传输性能的改善

蓝牙2.0+EDR规范新增DH分组没有有效的纠错机制,其抗干扰能力差。通过在新规范中加入BCH编码和交织编码,以改善蓝牙的数据传输吞吐量及抗干扰能力。对于新增的数据分组,根据蓝牙标准协议,推导了相应的分组特性;建立了GE信道下数据传输速率与信道突发错误水平的关系模型;获得了在不同信道突发错误水平下的数据传输吞吐量。结果表明,在蓝牙2.0+EDR新规范中加入BCH编码和交织编码,在较高突发错误水平的信道中,其数据传输吞吐量提高了一倍以上,明显改善了数据传输的抗干扰能力。     

浅析影响汉语旅游宣传资料英译的因素

本文从旅游宣传资料的定义、分类、功能以及语言特点入手,分析了汉语旅游宣传资料英译中出现的问题。通过分析发现：中西方巨大的文化差异是造成旅游宣传资料汉英翻译失误的主要原因,而文化上的差异导致中西方语言上的不同,因而译者不但要掌握语言知识,更应具有跨文化意识。     

大学入学新生英语口语错误调查分析报告--以单、双向口语任务小样本为例

运用功能语法的相关理论了解大学生语言交际过程中产生的语言错误,同时进一步进行相关分析以了解错误的根源及可用纠错策略.研究表明加强词汇知识运用以及交际策略的训练、针对不同的对象进行课堂语言操练等方法可以有效提高学生语言交际的成功率.此研究对大学口语教学将有所帮助.