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Tuning parameter selection for nonparametric derivative estimation in random design 随机设计中非参数导数估计的参数选择
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-11-08 DOI: 10.1080/02331888.2023.2278042
Sisheng Liu, Richard Charnigo
AbstractEstimation of a function, or its derivatives via nonparametric regression requires selection of one or more tuning parameters. In the present work, we propose a tuning parameter selection criterion called DCp for nonparametric derivative estimation in random design. Our criterion is general in that it can be applied with any nonparametric estimation method which is linear in the observed outcomes. Charnigo et al. [A generalized Cp criterion for derivative estimation. Technometrics. 2011;53(3):238–253] had proposed a GCp criterion for a similar purpose, assuming values of the covariate to be fixed and constant error variance. Here we consider the setting with random design and non-constant error variance since the covariate values will not generally be fixed and equally spaced in real data applications. We justify DCp in this setting both theoretically and by simulation. We also illustrate use of DCp with two economics data sets.Keywords: Nonparametric derivative estimationempirical derivativetuning parameter selectionrandom covariateheteroskedasticity AcknowledgmentsWe gratefully acknowledge the coding work from Charnigo et al. [Citation3] since some of R code for our simulation study was adapted from their work. We thank the associate editor and two anonymous peer reviewers for constructive suggestions.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingSisheng Liu's research is supported by the Scientific Research Fund of Hunan Provincial Education Department [grant number 22B0037].
摘要通过非参数回归估计函数或其导数需要选择一个或多个调谐参数。在本工作中,我们提出了一种称为DCp的随机设计非参数导数估计的调谐参数选择准则。我们的准则是通用的,因为它可以应用于任何在观测结果中呈线性的非参数估计方法。Charnigo et al.[导数估计的广义Cp准则。]technometics . 2011;53(3): 238-253]提出了一个GCp标准,用于类似的目的,假设协变量的值是固定的,误差方差恒定。这里我们考虑随机设计和非恒定误差方差的设置,因为协变量值在实际数据应用中通常不会是固定的和等间隔的。我们从理论上和仿真上证明了DCp在这种情况下的合理性。我们还用两个经济数据集说明DCp的使用。关键词:非参数导数估计经验导数调整参数选择随机协变量异方差致谢感谢Charnigo等人的编码工作[引文3],因为我们模拟研究的一些R代码改编自他们的工作。我们感谢副主编和两位匿名同行审稿人提出的建设性意见。披露声明作者未报告潜在的利益冲突。刘思生的研究得到湖南省教育厅科研基金资助[批准号:22B0037]。
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引用次数: 0
Generalized log-logistic proportional hazard model: a non-penalty shrinkage approach 广义对数-逻辑比例风险模型:一种非惩罚收缩方法
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-11-08 DOI: 10.1080/02331888.2023.2280072
Quinn Forzley, Shakhawat Hossain, Shahedul A. Khan
AbstractThis paper considers the pretest and shrinkage estimation methods for estimating regression parameters of the generalized log-logistic proportional hazard (PH) model. This model is a simple extension of the log-logistic model, which is closed under the PH relationship. The generalized log-logistic PH model also has attributes similar to those of the Weibull model. We consider this model for right-censored data when some parameters shrink to a restricted subspace. This subspace information on the parameters is used to shrink the unrestricted model estimates toward the restricted model estimates. We then optimally combine the unrestricted and restricted estimates in order to define pretest and shrinkage estimators. Although this estimation procedure may increase bias, it also reduces the overall mean squared error. The efficacy of the proposed model and estimation techniques are shown using a simulation study as well as an application to real data. We also compare the performance of generalized log-logistic, Weibull, and Cox PH models for unimodal and increasing hazards. The shrinkage estimator poses less risk than the maximum likelihood estimator when the shrinkage dimension exceeds two; this is shown through simulation and real data applications.Keywords: Generalized log-logistic distributionWeibull distributionCox proportional hazard modelmaximum likelihoodMonte Carlo simulationshrinkage and pretest estimators2020 Mathematics Subject Classification: 62N02 AcknowledgementsThe authors are thankful to the editor, associate editor, and two referees for their valuable and insightful comments, which have significantly enhanced the quality of this article.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis research work was partially supported by NSERC through Discovery Grants to S Hossain (#419428) and SA Khan (#368532).
摘要本文研究了广义对数-逻辑比例风险(PH)模型回归参数估计的预检验和收缩估计方法。该模型是逻辑-逻辑模型的简单扩展,在PH关系下是封闭的。广义逻辑-逻辑PH模型也具有与威布尔模型相似的属性。我们考虑了当某些参数收缩到受限子空间时的右截尾数据模型。该参数的子空间信息用于将不受限制的模型估计缩小到受限制的模型估计。然后,我们最优地结合无限制和限制估计,以定义预测试和收缩估计。虽然这种估计过程可能会增加偏差,但它也减少了总体均方误差。通过仿真研究和对实际数据的应用,证明了所提出的模型和估计技术的有效性。我们还比较了广义逻辑逻辑、威布尔和Cox PH模型在单峰和增加危险情况下的性能。当收缩维数大于2时,收缩估计量的风险小于最大似然估计量;通过仿真和实际数据应用证明了这一点。关键词:广义逻辑-逻辑分布;威布尔分布;cox比例风险模型;最大似然;蒙特卡罗模拟;收缩和预检验估计;2020数学学科分类:62N02致谢作者感谢编辑、副编辑和两位审稿人宝贵而深刻的意见,他们大大提高了本文的质量。披露声明作者未报告潜在的利益冲突。本研究工作部分由NSERC通过发现补助金支持S侯赛因(#419428)和SA Khan(#368532)。
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引用次数: 0
Moderate deviations for the mildly stationary autoregressive model with dependent errors 具有相关误差的轻度平稳自回归模型的中等偏差
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-11-06 DOI: 10.1080/02331888.2023.2278034
Hui Jiang, Guangyu Yang, Mingming Yu
In this paper, we consider the normalized least squares estimator of the parameter in a mildly stationary first-order autoregressive (AR(1)) model with dependent errors which are modeled as a mildly stationary AR(1) process. By martingale methods, we establish the moderate deviations for the least squares estimators of the regressor and error, which can be applied to understand the near-integrated second order autoregressive processes. As an application, we also obtain the moderate deviations for the Durbin-Watson statistic.
本文研究了一类具有相关误差的温和平稳一阶自回归(AR(1))模型参数的归一化最小二乘估计,该模型被建模为温和平稳AR(1)过程。利用鞅方法,建立了回归量和误差的最小二乘估计的中等偏差,可用于理解近积分二阶自回归过程。作为应用,我们也得到了Durbin-Watson统计量的中等偏差。
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引用次数: 0
Expectile trace regression via low-rank and group sparsity regularization 期望跟踪回归通过低秩和组稀疏正则化
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-11-03 DOI: 10.1080/02331888.2023.2269588
Ling Peng, Xiangyong Tan, Peiwen Xiao, Zeinab Rizk, Xiaohui Liu
AbstractTrace regression has received a lot of attention due to its ability to account for matrix-type covariates, including panel data, images, and genomic microarrays as special cases. However, most of its existing research focuses on the case of mean regression. In this paper, we consider the expectile trace regression, which can provide a more diversified picture of the regression relationship at different expectiles, via the low-rank and group sparsity regularization. The upper bound for the statistical rate of convergence of the regularized estimator is established under some mild conditions. Some simulations, as well as a real data example, are also provided to illustrate the finite sample performance of the developed expectile trace regression.Keywords: Expectile trace regressionlow-rankupper boundconvergence ratematrix-type covariates2020 Mathematics Subject Classifications: 62J9962H12 AcknowledgementsThe authors thank one anonymous referee and the associate editor for their valuable comments, which have led to many improvements to this paper.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingLing Peng's research was supported by the NSF of China (Grant No. 12201259), Jiangxi Provincial NSF (Grant No. 20224BAB211008), and the Science & Technology research project of the Education Department of Jiangxi Province (Grant No. GJJ2200537). Xiangyong Tan's research was supported by the NSF of China (Grant No. 12201260), Jiangxi Provincial NSF (Grant No. 20212BAB211010), and China Postdoctoral Science Foundation (2022M711425). Xiaohui Liu's research is supported by NSF of China (Grant No. 11971208), the National Social Science Foundation of China (21&ZD152), and the Outstanding Youth Fund Project of the Science and Technology Department of Jiangxi Province (No. 20224ACB211003).
摘要痕量回归由于能够解释矩阵型协变量,包括面板数据、图像和基因组微阵列等特殊情况而受到广泛关注。然而,现有的研究大多集中在均值回归的情况下。在本文中,我们考虑期望轨迹回归,它可以提供一个更多样化的图像在不同的期望,通过低秩和群稀疏正则化的回归关系。在一些温和的条件下,给出了正则化估计量的统计收敛率的上界。通过仿真和一个实际数据实例,说明了所开发的期望轨迹回归的有限样本性能。关键词:期望轨迹回归低秩上界收敛率矩阵型协变量2020数学学科分类:62J9962H12致谢作者感谢一位匿名审稿人和副编辑的宝贵意见,他们对本文进行了许多改进。披露声明作者未报告潜在的利益冲突。彭玲的研究得到中国国家自然科学基金(批准号:12201259)、江西省国家自然科学基金(批准号:20224BAB211008)和江西省教育厅科技研究项目(批准号:20224BAB211008)资助。GJJ2200537)。谭湘永的研究得到中国国家自然科学基金(资助号12201260)、江西省国家自然科学基金(资助号20212BAB211010)和中国博士后科学基金(资助号2022M711425)的资助。刘晓辉的研究得到中国国家自然科学基金(资助项目No. 11971208)、国家社会科学基金(No. 21&ZD152)和江西省科技厅杰出青年基金项目(No. 20224ACB211003)的资助。
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引用次数: 0
Uniformly strong consistency and the rates of asymptotic normality for the edge frequency polygons 边频多边形的一致强相合性和渐近正态率
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-10-10 DOI: 10.1080/02331888.2023.2268314
Mengmei Xi, Chunhua Wang, Xuejun Wang
AbstractIn this paper, we primarily focus on the edge frequency polygon estimator of f(x), which represents the probability density function of a sequence of φ-mixing random variables {Xi,i≥1}. We establish the uniformly strong consistency and the convergence rate of asymptotic normality for the edge frequency polygon estimator under suitable conditions. Notably, the convergence rate achieves O(n−1/6), which is more precise compared to the corresponding rate mentioned in the existing literature. Additionally, we present simulation studies to validate the theoretical results.Keywords: Berry–Esseen boundsuniformly strong consistencydensity functionedge frequency polygon estimatorMathematical Subject Classifications: 60E0562G20 AcknowledgementsThe authors are most grateful to the Editor and anonymous referee for carefully reading the manuscript and valuable suggestions which helped in improving an earlier version of this paper.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingSupported by the National Social Science Foundation of China (22BTJ059), the National Natural Science Foundation of China (12201600), and the Natural Science Foundation of Anhui Province (2108085MA06), and the Postdoctoral Science Foundation of China (2022M713056).
在适当的条件下,给出了边频多边形估计的一致强相合性和渐近正态性的收敛速度。值得注意的是,收敛速度达到了O(n−1/6),与已有文献中相应的收敛速度相比,收敛速度更加精确。此外,我们提出了仿真研究来验证理论结果。关键词:Berry-Esseen界均匀强一致性密度函数边缘频率多边形估计数学学科分类:60E0562G20致谢作者非常感谢编辑和匿名审稿人仔细阅读稿件并提出宝贵意见,帮助改进了本文的早期版本。披露声明作者未报告潜在的利益冲突。项目资助:国家社会科学基金项目(22BTJ059)、国家自然科学基金项目(12201600)、安徽省自然科学基金项目(2108085MA06)、中国博士后科学基金项目(2022M713056)。
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引用次数: 0
Asymptotics of lower dimensional zero-density regions 低维零密度区域的渐近性
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-09-25 DOI: 10.1080/02331888.2023.2262665
Hengrui Luo, Steven N. MacEachern, Mario Peruggia
AbstractTopological data analysis (TDA) allows us to explore the topological features of a dataset. Among topological features, lower dimensional ones have recently drawn the attention of practitioners in mathematics and statistics due to their potential to aid the discovery of low dimensional structure in a data set. However, lower dimensional features are usually challenging to detect based on finite samples and using TDA methods that ignore the probabilistic mechanism that generates the data. In this paper, lower dimensional topological features occurring as zero-density regions of density functions are introduced and thoroughly investigated. Specifically, we consider sequences of coverings for the support of a density function in which the coverings are comprised of balls with shrinking radii. We show that, when these coverings satisfy certain sufficient conditions as the sample size goes to infinity, we can detect lower dimensional, zero-density regions with increasingly higher probability while guarding against false detection. We supplement the theoretical developments with the discussion of simulated experiments that elucidate the behaviour of the methodology for different choices of the tuning parameters that govern the construction of the covering sequences and characterize the asymptotic results.Keywords: Topological data analysiscovering constructionzero-density regions AcknowledgmentsWe thank the anonymous referee, whose comments greatly improve the article. We thank the AE for helpful comments and handling.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis material is based upon work supported by the National Science Foundation [grants numbers DMS-1613110, DMS-2015552, and SES-1921523].
拓扑数据分析(TDA)允许我们探索数据集的拓扑特征。在拓扑特征中,低维特征最近引起了数学和统计学从业者的注意,因为它们有可能帮助发现数据集中的低维结构。然而,基于有限样本和使用忽略生成数据的概率机制的TDA方法来检测低维特征通常具有挑战性。本文引入并深入研究了密度函数中作为零密度区域的低维拓扑特征。具体来说,我们考虑用于支持密度函数的覆盖序列,其中覆盖序列由半径缩小的球组成。我们证明,当这些覆盖满足一定的充分条件时,随着样本量趋于无穷,我们可以以越来越高的概率检测到低维、零密度的区域,同时防止误检测。我们用模拟实验的讨论来补充理论发展,这些实验阐明了控制覆盖序列构造和表征渐近结果的调谐参数的不同选择的方法的行为。关键词:结构零密度区域拓扑数据分析致谢感谢匿名审稿人,他的意见对本文的改进有很大的帮助。我们感谢AE提供的有益意见和处理。披露声明作者未报告潜在的利益冲突。本材料基于美国国家科学基金会支持的工作[资助号:DMS-1613110, DMS-2015552和SES-1921523]。
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引用次数: 7
Automatic selection by penalized asymmetric Lq-norm in a high-dimensional model with grouped variables 具有分组变量的高维模型中惩罚非对称lq -范数的自动选择
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-09-03 DOI: 10.1080/02331888.2023.2256948
Angelo Alcaraz, Gabriela Ciuperca
The paper focuses on the automatic selection of the grouped explanatory variables in a high-dimensional model, when the model blue error is asymmetric. After introducing the model and notations, we define the adaptive group LASSO expectile estimator for which we prove the oracle properties: the sparsity and the asymptotic normality. Afterwards, the results are generalized by considering the asymmetric Lq-norm loss function. The theoretical results are obtained in several cases with respect to the number of variable groups. This number can be fixed or dependent on the sample size n, with the possibility that it is of the same order as n. Note that these new estimators allow us to consider weaker assumptions on the data and on the model errors than the usual ones. Simulation study demonstrates the competitive performance of the proposed penalized expectile regression, especially when the samples size is close to the number of explanatory variables and model errors are asymmetrical. An application on air pollution data is considered.
研究了高维模型中蓝误差不对称情况下分组解释变量的自动选择问题。在引入模型和符号之后,我们定义了自适应群LASSO期望估计量,并证明了其稀疏性和渐近正态性。然后,通过考虑非对称lq -范数损失函数,推广了结果。在若干情况下,得到了关于变量群数目的理论结果。这个数字可以是固定的,也可以依赖于样本大小n,它可能与n具有相同的阶数。请注意,这些新的估计器允许我们考虑对数据和模型误差的较弱假设,而不是通常的假设。仿真研究表明,当样本量接近解释变量数量和模型误差不对称时,所提出的惩罚期望回归具有较好的竞争性能。考虑了空气污染数据的应用。
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引用次数: 0
On asymptotic properties of spacings 关于间隔的渐近性质
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-09-03 DOI: 10.1080/02331888.2023.2260037
Alexandre Berred, Alexei Stepanov
AbstractIn this work, we investigate spacings based on order statistics obtained from continuous distribution functions. At the beginning of the paper, we present distributional results for spacings and a method of classification of distributions according to their tails. Then we use this method to derive asymptotic results for spacings. By applying some special versions of Borel–Cantelli lemma, we obtain their strong limit results. At the end of the paper, we present some illustrative examples.Keywords: Order statisticsspacingslimit resultsMSC2020-Mathematical Sciences Classification System: 6062 AcknowledgmentsThe authors are deeply indebted to the two anonymous Reviewers for their interesting comments and remarks. The work of the second author was supported by the Ministry of Science and Higher Education of the Russian Federation (agreement no. 075-02-2021-1748).Disclosure statementNo potential conflict of interest was reported by the author(s).
摘要在本文中,我们研究了基于连续分布函数的阶统计量的间隔。在本文的开头,我们给出了间隔的分布结果和一种根据其尾部对分布进行分类的方法。然后利用该方法得到了间隔的渐近结果。利用Borel-Cantelli引理的一些特殊版本,得到了它们的强极限结果。在论文的最后,我们给出了一些说明性的例子。关键词:序统计量;间距;限制结果;smsc2020 -数学科学分类系统:6062致谢作者非常感谢两位匿名审稿人的有趣评论和意见。第二作者的工作得到了俄罗斯联邦科学和高等教育部的支持(协议号:075-02-2021-1748)。披露声明作者未报告潜在的利益冲突。
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引用次数: 0
Integrated partially linear model for multi-centre studies with heterogeneity and batch effect in covariates 具有协变量异质性和批效应的多中心研究的部分线性综合模型
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-09-03 DOI: 10.1080/02331888.2023.2258429
Lei Yang, Yongzhao Shao
AbstractMulti-centre study is increasingly used for borrowing strength from multiple research groups to obtain reproducible study findings. Regression analysis is widely used for analysing multi-group studies, however, some of the regression predictors are nonlinear and/or often measured with batch effects. Also, the group compositions are potentially heterogeneous across different centres. The conventional pooled data analysis can cause biased regression estimates. This paper proposes an integrated partially linear regression model (IPLM) to account for predictor's nonlinearity, general batch effect, group composition heterogeneity, and potential measurement-error in covariates simultaneously. A local linear regression-based approach is employed to estimate the nonlinear component and a regularization procedure is introduced to identify the predictors' effects. The IPLM-based method has estimation consistency and variable-selection consistency. Moreover, it has a fast computing algorithm and its effectiveness is supported by simulation studies. A multi-centre Alzheimer's disease research project is provided to illustrate the proposed IPLM-based analysis.Keywords: Multi-centre studydata harmonizationpartially linear regression modelgeneral batch effectsgroup composition heterogeneity AcknowledgementsThe authors would like to thank the reviewers and the associate editor for careful reading and for many constructive suggestions. The authors would like to thank Drs. Mony de Leon, Ricardo Osorio, and Elizabeth Pirraglia for sharing with us the NYU Alzheimer's disease data sets used in Section 5 for the illustration of our proposed model and analysis. The NYU study data are available from figshare (https://figshare.com/s/16d233d4822b810bcd9b, DOI: 10.6084/m9.figshare.5758554). One part of the data used in the preparation of the example in Section 5 of this article was obtained from the Alzheimers Disease Neuroimaging Initiative (ADNI) database (http://adni.loni.usc.edu/data-samples/access-data/). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in the design, analysis or writing of this report. A complete list of ADNI investigators is at: http://adni.loni.usc.edu/wpcontent/uploads/how to apply/ADNI Acknowledgement List.pdf.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis research was partially supported by the United States National Institute of Health grants (NIA grants P30AG066512, P01AG060882, NCI grants P50CA225450, P30CA016087) and Center for Disease Control and Prevention (CDC) grant U01OH012486.
摘要多中心研究越来越多地利用多个研究小组的力量来获得可重复的研究结果。回归分析被广泛用于分析多组研究,然而,一些回归预测因子是非线性的,并且/或者经常用批效应来测量。此外,在不同的中心,群体组成可能是异质的。传统的汇总数据分析可能导致偏倚回归估计。本文提出了一种综合部分线性回归模型(IPLM),以同时考虑预测因子的非线性、一般批效应、群体组成异质性和协变量中潜在的测量误差。采用基于局部线性回归的方法来估计非线性分量,并引入正则化过程来识别预测因子的影响。基于iplm的方法具有估计一致性和变量选择一致性。此外,该方法具有快速的计算算法,仿真研究证明了其有效性。提供了一个多中心阿尔茨海默病研究项目来说明所提出的基于iplm的分析。关键词:多中心研究数据协调部分线性回归模型一般批效应组组成异质性致谢作者感谢审稿人和副编辑的认真阅读和许多建设性的建议。作者们要感谢dr。mondeleon, Ricardo Osorio和Elizabeth piraglia与我们分享了第5节中使用的纽约大学阿尔茨海默病数据集,用于说明我们提出的模型和分析。纽约大学的研究数据可从figshare (https://figshare.com/s/16d233d4822b810bcd9b, DOI: 10.6084/m9.figshare.5758554)获得。本文第5节中准备示例所使用的部分数据来自阿尔茨海默病神经影像学倡议(ADNI)数据库(http://adni.loni.usc.edu/data-samples/access-data/)。因此,ADNI内部的调查人员参与了ADNI的设计和实施和/或提供了数据,但未参与本报告的设计、分析或撰写。ADNI研究人员的完整名单可在:http://adni.loni.usc.edu/wpcontent/uploads/how申请/ADNI确认名单。pdf.披露声明作者未报告潜在的利益冲突。本研究得到了美国国立卫生研究院拨款(NIA拨款P30AG066512, P01AG060882, NCI拨款P50CA225450, P30CA016087)和疾病控制与预防中心(CDC)拨款U01OH012486的部分支持。
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引用次数: 0
An optimization method for change-point monitoring in finite samples sequence 有限样本序列变点监测的优化方法
4区 数学 Q2 STATISTICS & PROBABILITY Pub Date : 2023-09-03 DOI: 10.1080/02331888.2023.2258249
Dong Han, Fugee Tsung, Jinguo Xian
AbstractThis article proposes a method of optimizing control chart (sequential test) to detect an abnormal change in a sequence of finite or even small samples with the unknown change-point and the unknown post-change probability distribution. We not only introduced a performance measure for a given charting statistic to evaluate the detection effect of a control chart, but also constructed an optimal control chart under the measure. The effect of optimization method was illustrated by numerical simulations of three optimized Shewhart, CUSUM and EWMA control charts, and a real data example.Keywords: Optimization of control chartchange-point detectionfinite samplesMSC 2010 Subject Classifications: Primary 62L10secondary 62L15 AcknowledgmentsWe sincerely thank the two reviewers for their precious comments on the manuscript.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work is supported by RGC Competitive Earmarked Research Grants and National Natural Science Foundation of China (11531001).
摘要本文提出了一种优化控制图(序列检验)的方法,用于检测具有未知变化点和未知变化后概率分布的有限甚至小样本序列的异常变化。引入了给定图表统计量的性能度量来评价控制图的检测效果,并在此度量下构造了最优控制图。通过优化后的Shewhart控制图、CUSUM控制图和EWMA控制图的数值仿真,以及一个实际数据算例,说明了优化方法的效果。关键词:控制图优化变点检测有限样本msc 2010主题分类:初级62l10次级62L15致谢我们衷心感谢两位审稿人对稿件的宝贵意见。披露声明作者未报告潜在的利益冲突。项目资助:中国国家自然科学基金(11531001)。
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引用次数: 0
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