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Related papers: Sparse Functional Boxplots for Multivariate Curves

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Covariance function estimation is a fundamental task in multivariate functional data analysis and arises in many applications. In this paper, we consider estimating sparse covariance functions for high-dimensional functional data, where the…

Statistics Theory · Mathematics 2022-07-15 Qin Fang , Shaojun Guo , Xinghao Qiao

Functional data analysis is ubiquitous in most areas of sciences and engineering. Several paradigms are proposed to deal with the dimensionality problem which is inherent to this type of data. Sparseness, penalization, thresholding, among…

Methodology · Statistics 2018-09-05 Rodney V. Fonseca , Aluísio Pinheiro

Inversion codes are numerical tools used for the inference of physical properties from the observations. Despite their success, the quality of current spectropolarimetric observations and those expected in the near future presents a…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. Asensio Ramos , J. de la Cruz Rodriguez

Nonparametric estimation of the mean and covariance functions is ubiquitous in functional data analysis and local linear smoothing techniques are most frequently used. Zhang and Wang (2016) explored different types of asymptotic properties…

Statistics Theory · Mathematics 2025-01-28 Shaojun Guo , Dong Li , Xinghao Qiao , Yizhu Wang

In this paper we introduce a micro-clustering strategy for Functional Boxplots. The aim is to summarize a set of streaming time series splitted in non overlapping windows. It is a two step strategy which performs at first, an on-line…

Methodology · Statistics 2012-12-13 Elvira Romano , Antonio Balzanella

Functional time series analysis, whether based on time of frequency domain methodology, has traditionally been carried out under the assumption of complete observation of the constituent series of curves, assumed stationary. Nevertheless,…

Methodology · Statistics 2020-04-02 Tomáš Rubín , Victor M. Panaretos

The direction of outlyingness is crucial to describing the centrality of multivariate functional data. Motivated by this idea, we generalize classical depth to directional outlyingness for functional data. We investigate theoretical…

Methodology · Statistics 2018-04-24 Wenlin Dai , Marc G. Genton

In this paper, we propose a functional analysis of a set of individual space-speed profiles corresponding to speed as function of the distance traveled by the vehicle from an initial point. This functional analysis begins with a functional…

Applications · Statistics 2014-01-21 Cindie Andrieu , Guillaume Saint Pierre , Xavier Bressaud

We propose a computationally simple framework for clustering functional data based on Gaussian-process-generated random projections. In this approach, each curve is first projected onto a large collection of independent Gaussian process…

Methodology · Statistics 2026-05-22 Sourav Chakrabarty , Anirvan Chakraborty , Shyamal K. De

We present the FuSSO, a functional analogue to the LASSO, that efficiently finds a sparse set of functional input covariates to regress a real-valued response against. The FuSSO does so in a semi-parametric fashion, making no parametric…

In this paper, we address the problem of conducting statistical inference in settings involving large-scale data that may be high-dimensional and contaminated by outliers. The high volume and dimensionality of the data require distributed…

Machine Learning · Statistics 2022-11-30 Emadaldin Mozafari-Majd , Visa Koivunen

Deep neural networks have emerged as powerful tools for learning operators defined over infinite-dimensional function spaces. However, existing theories frequently encounter difficulties related to dimensionality and limited…

Machine Learning · Computer Science 2026-05-12 Jianfei Li , Shuo Huang , Han Feng , Ding-Xuan Zhou , Gitta Kutyniok

We aim to develop simultaneous inference tools for the mean function of functional data from sparse to dense. First, we derive a unified Gaussian approximation to construct simultaneous confidence bands of mean functions based on the…

Methodology · Statistics 2024-02-01 Leheng Cai , Qirui Hu

Particulate matter data now include various particle sizes, which often manifest as a collection of curves observed sequentially over time. When considering 51 distinct particle sizes, these curves form a high-dimensional functional time…

Methodology · Statistics 2025-10-03 Han Lin Shang , Israel Martinez Hernandez

We consider functional linear regression models where functional outcomes are associated with scalar predictors by coefficient functions with shape constraints, such as monotonicity and convexity, that apply to sub-domains of interest. To…

Methodology · Statistics 2025-05-09 Kyunghee Han , Yeonjoo Park , Soo-Young Kim

The classification of multivariate functional data is an important task in scientific research. Unlike point-wise data, functional data are usually classified by their shapes rather than by their scales. We define an outlyingness matrix by…

Methodology · Statistics 2018-04-24 Wenlin Dai , Marc G. Genton

This paper applies conformal prediction techniques to compute simultaneous prediction bands and clustering trees for functional data. These tools can be used to detect outliers and clusters. Both our prediction bands and clustering trees…

Machine Learning · Statistics 2013-02-27 Jing Lei , Alessandro Rinaldo , Larry Wasserman

Multivariate functional data from a complex system are naturally high-dimensional and have complex cross-correlation structure. The complexity of data structure can be observed as that (1) some functions are strongly correlated with similar…

Machine Learning · Statistics 2018-04-12 Chen Zhang , Hao Yan , Seungho Lee , Jianjun Shi

We consider inference for misaligned multivariate functional data that represents the same underlying curve, but where the functional samples have systematic differences in shape. In this paper we introduce a new class of generally…

Applications · Statistics 2023-01-23 Niels Lundtorp Olsen , Bo Markussen , Lars Lau Rakêt

We propose a new method to visualize and detect shape outliers in samples of curves. In functional data analysis we observe curves defined over a given real interval and shape outliers are those curves that exhibit a different shape from…

Computation · Statistics 2013-10-01 Ana Arribas-Gil , Juan Romo