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A theoretic study of a distance-based regression model

Science China Mathematics 2019年第5期62卷 979-998页

作者： Jialu Li Wei Zhang Sanguo Zhang Qizhai Li School of Mathematics and Statistics Beijing Institute of Technology Biostatistics and Bioinformatics Branch National Institute of Child Health and Human Development School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of Sciences LSC NCMIS Academy of Mathematics and Systems Science Chinese Academy of Sciences

The distance-based regression model has many applications in analysis of multivariate response regression in various ?elds, such as ecology, genomics, genetics, human microbiomics, and neuroimaging. It yields a pseudo F test statistic that assesses the relation between the distance(dissimilarity) of the subjects and the predictors of interest. Despite its popularity in recent decades, the statistical properties of the pseudo F test statistic have not been revealed to our knowledge. This study derives the asymptotic properties of the pseudo F test statistic using spectral decomposition under the matrix normal assumption, when the utilized dissimilarity measure is the Euclidean or Mahalanobis distance. The pseudo F test statistic with the Euclidean distance has the same distribution as the quotient of two Chi-squared-type mixtures. The denominator and numerator of the quotient are approximated using a random variable of the form ξχ_d^2+ η, and the approximate error bound is given. The pseudo F test statistic with the Mahalanobis distance follows an F distribution.In simulation studies, the approximated distribution well matched the "exact" distribution obtained by the permutation procedure. The obtained distribution was further validated on H1N1 in?uenza data, aging human brain data, and embryonic imprint data.

关键词： distance-based regression Euclidean pseudo F test statistic Mahalanobis

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Comparison of Analyses of Genetic Structure among Chinese Indigenous Chicken Breeds using distance-based and Model-based Methods

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畜牧兽医学报 2009年第S1期40卷 8-12页

作者： LI Hui-fang CHEN Kuan-wei HAN Wei ZHANG Xue-yu GAO Yu-shi CHEN Guo-hong ZHU Yun-fen WANG Qiang Institute of Poultry Science Chinese Academy of Agricultural Sciences

The Nei's improved genetic distance(DA)and gene flow(Nm)were measured using sixteen microsatellite markers.Dendograms based on DA genetic distance using the neighbor-joining(NJ)method and STRUCTURE program were constructed to analyze the genetic structure and relationship among 10 Chinese indigenous chicken breeds.The results showed that dendograms of DA genetic distance using the NJ method divided the 10 chicken breeds into two main clusters;one consisted of breeds of low weight body(CHA,TTB,XIA,GUS and BAI),the other contained heavier breeds(LAN,DAG,YOU,XIS and LUY).In the lighter breeds,TIB and CHA clustered together,as did XIA and GUS.In the heavier breeds,XIS and LUY was clustered together in one branch,but LAN,DAG and YOU clustered in independent branches.The results were consistent with Nm estimates among the 10 indigenous chicken breeds.The STRUCTURE program properly inferred the presence of genetic structure despite not pre-defining the origin of individuals.The genetic cluster inferred by STRUCTURE was basically the same as that from the DA distance clustering method.An advantage of the STRUCTURE program was its ability to identify the migrants and admixed individuals in the 10 chicken populations;this could not be achieved by use of the DA distance clustering method.

关键词： microsatellite Chinese chicken breeds distance-based clustering method Model-based clustering method

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Creating Effective Self-Management for Older Adults with Type 2 Diabetes and Cognitive Impairment

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Advances in Aging Research 2015年第2期4卷 33-41页

作者： Cameron J. Camp Kathleen Fox Michael J. Skrajner Vincent Antenucci Jessica Haberman Center for Applied Research Solon USA Hearthstone Alzheimer’s Care Woburn USA Cleveland State University Cleveland USA

The primary objective of the study was to determine whether a distanced-based educational in-tervention would result in positive health outcomes for persons with both DM and cognitive impairment. Older adults with Type 2 diabetes (Diabetes Mellitus—DM) who also have cognitive impairment such as Mild Cognitive Impairment (MCI) or early stage dementia are both challenged and at risk when attempting to live independently. The ability to effectively monitor blood glucose levels and diet and exercise regimens often is severely constrained by the combination of DM and the presence of Mild Cognitive Impairment (MCI) or early stage dementia. We describe an exploratory study funded by the National Institute of Diabetes Digestive and Kidney Diseases (NIDDK) in which Certified Diabetic Educators (CDEs) were linked with 40 older adult with DM and cognitive impairment using iPads and the internet. CDEs presented personalized education sessions to participants, and 18 of the participants also received a cognitive intervention called Spaced Retrieval (SR), which is designed to train the effective use of strategies to enhance medication compliance and reach other goals. Blood glucose and cholesterol measures were assessed at baseline and at 2-, 4-, and 6-month post intervention. Hemoglobin A1c (HbA1c) levels initially declined from baseline after treatment but returned to baseline levels after 6 months. For low-density lipoprotein (LDL) cholesterol, a significant interaction effect was found for the Group × Time interaction. LDL levels increased from baseline after treatment for the control group, but showed decline after baseline in the SR group. Goals that were initially learned were retained, in general, at short-term follow-up, and self-efficacy increased significantly after training. Results show the need for follow-up and support after initial treatment, as well as the need to see if the effects produced by SR can be replicated and sustained with continued contact.

关键词： Type 2 Diabetes Cognitive Impairment distance-based Intervention Educational Intervention Spaced-Retrieval

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一种支持基于内容的图像检索的多维索引结构

一种支持基于内容的图像检索的多维索引结构

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第十八届全国数据库学术会议

作者：曹奎冯玉才袁芳华中科技大学计算机学院

1.引言多维索引结构是基于内容的图像检索(Content-based Image Retrieval,CBIR)研究的一个基本问题。由于图像特征的表示一般均是高维向量,并且图像的距离度量也不仅限于距离,因此相似检索可视为在高维特征空间中寻找与指定点距离最近... 详细信息

1.引言多维索引结构是基于内容的图像检索(Content-based Image Retrieval,CBIR)研究的一个基本问题。由于图像特征的表示一般均是高维向量,并且图像的距离度量也不仅限于距离,因此相似检索可视为在高维特征空间中寻找与指定点距离最近的一组点的问题。我们注意到图像数据库一般都非常大(十万或百万

关键词： High-dimensional Index structure Similarity retrieval Metric space distance function distance-based

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Varying-coefficient based Distributed Formation Control of Multiple UAVs

Varying-coefficient Based Distributed Formation Control of M...

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第40届中国控制会议

作者： Zhang Hepeng Di Jian Yan Han Wang Xinghu Ji Haibo Department of Automation University of Science and Technology of China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control Engineering

This paper considers formation control of multiple unmanned aerial vehicles（UAVs） specified by Crazyflies. based on the inter-vehicle distance dynamics, a varying-coefficient distributed controller is developed that can preserve the noncollinearity and achieve globally exponentially convergence to the desired formation pattern. An experiment is done to illustrate the effectiveness of the developed varying-coefficient distributed controller. The experiment comparison with respect to the fixed-coefficient distributed controller is also provided, indicating that our method assures accurate formation. A video demo of the experiment is available at https://***/video/BV1iy4y1J74q.

关键词： Varying-coefficient distance-based Formation control Crazyflies

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一种改进的基于距离的离群挖掘算法

一种改进的基于距离的离群挖掘算法

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第二十四届中国数据库学术会议

作者：连凤娜吴锦林薛永生厦门大学信息科学与技术学院

引言Frawley定义数据挖掘为:"Data mining isdefined as the non-trivial extraction of implicit,previously unknown,and potentially useful informationfrom data."。现有的研究中大多主要集中

关键词： Outliers Data mining Intentional knowledge distance-based Frequent itemset

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