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Related papers: Functional Models for Time-Varying Random Objects

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The advent of data science has provided an increasing number of challenges with high data complexity. This paper addresses the challenge of space-time data where the spatial domain is not a planar surface, a sphere, or a linear network, but…

Methodology · Statistics 2022-08-09 Emilio Porcu , Philip A. White , Marc G. Genton

Time-varying non-Euclidean random objects are playing a growing role in modern data analysis, and periodicity is a fundamental characteristic of time-varying data. However, quantifying periodicity in general non-Euclidean random objects…

Methodology · Statistics 2025-10-22 Jiazhen Xu , Andrew T. A. Wood , Tao Zou

We propose nonparametric methods for functional linear regression which are designed for sparse longitudinal data, where both the predictor and response are functions of a covariate such as time. Predictor and response processes have smooth…

Statistics Theory · Mathematics 2016-08-16 Fang Yao , Hans-Georg Müller , Jane-Ling Wang

The semivarying coefficient models are widely used in the application of finance, economics, medical science and many other areas. The functional coefficients are commonly estimated by local smoothing methods, e.g. local linear estimator.…

Methodology · Statistics 2020-01-01 Heng Peng , Chuanlong Xie , Jingxin Zhao

This paper considers an estimation of semiparametric functional (varying)-coefficient quantile regression with spatial data. A general robust framework is developed that treats quantile regression for spatial data in a natural…

Statistics Theory · Mathematics 2014-02-06 Zudi Lu , Qingguo Tang , Longsheng Cheng

The functional linear model extends the notion of linear regression to the case where the response and covariates are iid elements of an infinite dimensional Hilbert space. The unknown to be estimated is a Hilbert-Schmidt operator, whose…

Statistics Theory · Mathematics 2016-12-22 Tung Pham , Victor Panaretos

Although large-scale visual foundation models (VFMs) achieve remarkable performance in semantic understanding, they still underperform in instance-aware dense prediction tasks. They exhibit different biases in representation: for instance,…

Computer Vision and Pattern Recognition · Computer Science 2026-05-19 Yachan Guo , JoseLuis Gomez Zurita , Danna Xue , Yi Xiao , AntonioManuel Lopez Pena

In the era of big data, integrating multi-source functional data to extract a subspace that captures the shared subspace across sources has attracted considerable attention. In practice, data collection procedures often follow…

Methodology · Statistics 2025-10-16 Chi Zhang , Peijun Sang , Yingli Qin

This paper develops a framework for the estimation of the functional mean and the functional principal components when the functions form a random field. More specifically, the data we study consist of curves $X(\mathbf{s}_k;t),t\in[0,T]$,…

Statistics Theory · Mathematics 2013-12-12 Siegfried Hörmann , Piotr Kokoszka

Rapid developments in satellite remote-sensing technology have enabled the collection of geospatial data on a global scale, hence increasing the need for covariance functions that can capture spatial dependence on spherical domains. We…

Methodology · Statistics 2022-08-17 Jian Cao , Jingjie Zhang , Zhuoer Sun , Matthias Katzfuss

This paper studies linear reconstruction of partially observed functional data which are recorded on a discrete grid. We propose a novel estimation approach based on approximate factor models with increasing rank taking into account…

Statistics Theory · Mathematics 2024-05-22 Maximilian Ofner , Siegfried Hörmann

This paper introduces a novel uncertainty quantification framework for regression models where the response takes values in a separable metric space, and the predictors are in a Euclidean space. The proposed algorithms can efficiently…

Statistics Theory · Mathematics 2024-05-09 Gábor Lugosi , Marcos Matabuena

In scientific applications, multivariate observations often come in tandem with temporal or spatial covariates, with which the underlying signals vary smoothly. The standard approaches such as principal component analysis and factor…

Statistics Theory · Mathematics 2019-10-15 Mark Koudstaal , Dengdeng Yu , Dehan Kong , Fang Yao

Fr\'echet regression extends the principles of linear regression to accommodate responses valued in generic metric spaces. While this approach has primarily focused on exploring relationships between Euclidean predictors and non-Euclidean…

Statistics Theory · Mathematics 2026-02-25 Chang Jun Im , Jeong Min Jeon

A median-radius framework for assessing centrality in multivariate data using median distances is proposed. Based on the proposed framework, a scale invariant measure of radial dispersion is defined and used to establish a depth function…

Methodology · Statistics 2026-05-14 Elsayed Elamir

We develop the basic building blocks of a frequency domain framework for drawing statistical inferences on the second-order structure of a stationary sequence of functional data. The key element in such a context is the spectral density…

Statistics Theory · Mathematics 2013-05-10 Victor M. Panaretos , Shahin Tavakoli

This work aims at performing Functional Principal Components Analysis (FPCA) with Horvitz-Thompson estimators when the observations are curves collected with survey sampling techniques. One important motivation for this study is that FPCA…

Statistics Theory · Mathematics 2009-12-19 Hervé Cardot , Mohamed Chaouch , Camelia Goga , Catherine Labruère

To infer eigenvalues of the infinite-dimensional Koopman operator, we study the leading eigenvalues of the autocovariance matrix associated with a given observable of a dynamical system. For any observable $f$ for which all the time-delayed…

Optimization and Control · Mathematics 2022-04-06 Yicun Zhen , Bertrand Chapron , Etienne Memin , Lin Peng

Assessing brain development for small infants is important for determining how the human brain grows during the early period of life when the rate of brain growth is at its peak. The development of MRI techniques has enabled the…

Applications · Statistics 2018-06-27 Alexander Petersen , Sean Deoni , Hans-Georg Müller

Human mortality patterns and trajectories in closely related populations are likely linked together and share similarities. It is always desirable to model them simultaneously while taking their heterogeneity into account. This paper…

Methodology · Statistics 2024-12-30 Ka Kin Lam , Bo Wang