Quarterly of Applied Mathematics最新文献_第10页

ESTIMATING DIFFEOMORPHIC MAPPINGS BETWEEN TEMPLATES AND NOISY DATA: VARIANCE BOUNDS ON THE ESTIMATED CANONICAL VOLUME FORM. 估计模板和噪声数据之间的微分同构映射:估计的规范体积形式的方差界。

IF 0.8 4区数学

Quarterly of Applied Mathematics Pub Date : 2019-01-01 Epub Date: 2018-11-20 DOI: 10.1090/qam/1527

Daniel J Tward, Partha P Mitra, Michael I Miller

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引用次数: 6

LOCALIZING DIFFERENTIALLY EVOLVING COVARIANCE STRUCTURES VIA SCAN STATISTICS. 通过扫描统计定位差异演化的协方差结构

IF 0.9 4区数学

Quarterly of Applied Mathematics Pub Date : 2019-01-01 Epub Date: 2018-12-17 DOI: 10.1090/qam/1522

Ronak Mehta, Hyunwoo J Kim, Shulei Wang, Sterling C Johnson, Ming Yuan, Vikas Singh

{"title":"LOCALIZING DIFFERENTIALLY EVOLVING COVARIANCE STRUCTURES VIA SCAN STATISTICS.","authors":"Ronak Mehta, Hyunwoo J Kim, Shulei Wang, Sterling C Johnson, Ming Yuan, Vikas Singh","doi":"10.1090/qam/1522","DOIUrl":"10.1090/qam/1522","url":null,"abstract":"Recent results in coupled or temporal graphical models offer schemes for estimating the relationship structure between features when the data come from related (but distinct) longitudinal sources. A novel application of these ideas is for analyzing group-level differences, i.e., in identifying if trends of estimated objects (e.g., covariance or precision matrices) are different across disparate conditions (e.g., gender or disease). Often, poor effect sizes make detecting the differential signal over the full set of features difficult: for example, dependencies between only a subset of features may manifest differently across groups. In this work, we first give a parametric model for estimating trends in the space of SPD matrices as a function of one or more covariates. We then generalize scan statistics to graph structures, to search over distinct subsets of features (graph partitions) whose temporal dependency structure may show statistically significant group-wise differences. We theoretically analyze the Family Wise Error Rate (FWER) and bounds on Type 1 and Type 2 error. Evaluating on US census data, we identify groups of states with cultural and legal overlap related to baby name trends and drug usage. On a cohort of individuals with risk factors for Alzheimer's disease (but otherwise cognitively healthy), we find scientifically interesting group differences where the default analysis, i.e., models estimated on the full graph, do not survive reasonable significance thresholds.","PeriodicalId":20964,"journal":{"name":"Quarterly of Applied Mathematics","volume":"77 2","pages":"357-398"},"PeriodicalIF":0.9,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8813049/pdf/nihms-1052984.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39893257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evolution partial differential equations with discontinuous data 具有不连续数据的演化偏微分方程

IF 0.8 4区数学

Quarterly of Applied Mathematics Pub Date : 2018-11-28 DOI: 10.1090/QAM/1526

T. Trogdon, G. Biondini

引用次数: 11

A tribute to Ulf Grenander 向Ulf Grenander致敬

IF 0.8 4区数学

Quarterly of Applied Mathematics Pub Date : 2018-11-26 DOI: 10.1090/QAM/1524

D. Mumford

引用次数: 1

Quantitative estimates of the field excited by an emitter in a narrow region between two circular inclusions 两个圆形夹杂物之间狭窄区域内发射器激发场的定量估计