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Related papers: Addressing Phase Discrepancies in Functional Data:…

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Image data are increasingly encountered and are of growing importance in many areas of science. Much of these data are quantitative image data, which are characterized by intensities that represent some measurement of interest in the…

Elastic Riemannian metrics have been used successfully in the past for statistical treatments of functional and curve shape data. However, this usage has suffered from an important restriction: the function boundaries are assumed fixed and…

Methodology · Statistics 2021-05-19 Darshan Bryner , Anuj Srivastava

Consistent experiment data are crucial to adjust parameters of physics models and to determine best estimates of observables. However, often experiment data are not consistent due to unrecognized systematic errors. Standard methods of…

Nuclear Theory · Physics 2018-03-05 Georg Schnabel

Functional data analysis almost always involves smoothing discrete observations into curves, because they are never observed in continuous time and rarely without error. Although smoothing parameters affect the subsequent inference,…

Methodology · Statistics 2025-04-07 Sunny G. W. Wang , Valentin Patilea , Nicolas Klutchnikoff

We present a Bayesian approach for modeling multivariate, dependent functional data. To account for the three dominant structural features in the data--functional, time dependent, and multivariate components--we extend hierarchical dynamic…

Methodology · Statistics 2019-07-02 Daniel R. Kowal , David S. Matteson , David Ruppert

Functional data analysis deals with data recorded densely over time (or any other continuum) with one or more observed curves per subject. Conceptually, functional data are continuously defined, but in practice, they are usually observed at…

Methodology · Statistics 2023-01-20 Chengqian Xian , Camila de Souza , John Jewell , Ronaldo Dias

Functional data are defined as realizations of random functions (mostly smooth functions) varying over a continuum, which are usually collected with measurement errors on discretized grids. In order to accurately smooth noisy functional…

Methodology · Statistics 2016-12-13 Jingjing Yang , Dennis D. Cox , Jong Soo Lee , Peng Ren , Taeryon Choi

A characteristic feature of functional data is the presence of phase variability in addition to amplitude variability. Existing functional regression methods do not handle time variability in an explicit and efficient way. In this paper we…

Methodology · Statistics 2014-04-22 Daniel Gervini

We propose modeling raw functional data as a mixture of a smooth function and a highdimensional factor component. The conventional approach to retrieving the smooth function from the raw data is through various smoothing techniques.…

Methodology · Statistics 2021-02-05 Yuan Gao , Han Lin Shang , Yanrong Yang

Bayesian methods have been very successful in quantifying uncertainty in physics-based problems in parameter estimation and prediction. In these cases, physical measurements y are modeled as the best fit of a physics-based model…

Data Analysis, Statistics and Probability · Physics 2015-02-06 Dave Higdon , Jordan D. McDonnell , Nicolas Schunck , Jason Sarich , Stefan M. Wild

In this work, a novel approach to Bayesian model calibration routines is developed which reinterprets the traditional definition of model discrepancy as defined by Kennedy and O'Hagan (KOH). The novelty lies in the integration of…

Methodology · Statistics 2026-03-13 Liam Myhill , Enrique Martinez Saez , Sez Russcher

Objective: Organ deformation models have the potential to improve delivery and reduce toxicity of radiotherapy, but existing data-driven motion models are based on either patient-specific or population data. We propose to combine population…

Time warping function provides a mathematical representation to measure phase variability in functional data. Recent studies have developed various approaches to estimate optimal warping between functions and provide non-Euclidean models.…

Methodology · Statistics 2022-04-15 Yijia Ma , Xinyu Zhou , Wei Wu

The analysis of multivariate functional curves has the potential to yield important scientific discoveries in domains such as healthcare, medicine, economics and social sciences. However, it is common for real-world settings to present…

Methodology · Statistics 2024-07-23 Tui Nolan , Sylvia Richardson , Hélène Ruffieux

Functional data often exhibit both amplitude and phase variation around a common base shape, with phase variation represented by a so called warping function. The process removing phase variation by curve alignment and inference of the…

Methodology · Statistics 2018-06-26 Eric Fu , Nancy Heckman

We introduce a novel geometric framework for separating the phase and the amplitude variability in functional data of the type frequently studied in growth curve analysis. This framework uses the Fisher-Rao Riemannian metric to derive a…

Statistics Theory · Mathematics 2015-03-19 Anuj Srivastava , Wei Wu , Sebastian Kurtek , Eric Klassen , J. S. Marron

The use of mathematical models to make predictions about tumor growth and response to treatment has become increasingly more prevalent in the clinical setting. The level of complexity within these models ranges broadly, and the calibration…

Quantitative Methods · Quantitative Biology 2021-12-28 Allison L. Lewis , Kathleen M. Storey , Heyrim Cho , Anna C. Zittle

High-dimensional data with hundreds of thousands of observations are becoming commonplace in many disciplines. The analysis of such data poses many computational challenges, especially when the observations are correlated over time and/or…

Computation · Statistics 2011-08-05 Sylvie Tchumtchoua , David B. Dunson , Jeffrey S. Morris

In multivariate functional data analysis, different functional covariates often exhibit homogeneity. The covariates with pronounced homogeneity can be analyzed jointly within the same group, offering a parsimonious approach to modeling…

Methodology · Statistics 2024-10-24 Shuhao Jiao , Ngai-Hang Chan

This work introduces a Bayesian smoothing approach for the joint graduation of mortality rates across multiple populations. In particular, dynamical linear models are used to induce smoothness across ages through structured dependence,…