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Open AccessJournal ArticleDOI

Functional Data Analysis

TLDR
In this article, the authors provide an overview of FDA, starting with simple statistical notions such as mean and covariance functions, then covering some core techniques, the most popular of which is functional principal component analysis (FPCA).
Abstract
With the advance of modern technology, more and more data are being recorded continuously during a time interval or intermittently at several discrete time points. These are both examples of functional data, which has become a commonly encountered type of data. Functional data analysis (FDA) encompasses the statistical methodology for such data. Broadly interpreted, FDA deals with the analysis and theory of data that are in the form of functions. This paper provides an overview of FDA, starting with simple statistical notions such as mean and covariance functions, then covering some core techniques, the most popular of which is functional principal component analysis (FPCA). FPCA is an important dimension reduction tool, and in sparse data situations it can be used to impute functional data that are sparsely observed. Other dimension reduction approaches are also discussed. In addition, we review another core technique, functional linear regression, as well as clustering and classification of functional d...

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Citations
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Journal ArticleDOI

Adaptive LASSO estimation for functional hidden dynamic geostatistical models

TL;DR: In this paper , a model selection algorithm based on a penalized maximum likelihood estimator for functional hidden dynamic geostatistical models (f-HDGM) is proposed, which employs a classic mixed-effect regression structure with embedded spatio-temporal dynamics to model georeferenced data observed in a functional domain.

Bayesian functional linear regression estimation. Extension to scalar and categorical covariates

TL;DR: Grollemund et al. as mentioned in this paper extend the Bliss method to a more general model that also contains categorical and scalar covariates, and propose an extension of the Bliss model and how to estimate the parameters in an interpretable way.
Journal ArticleDOI

Single-index partially functional linear quantile regression

TL;DR: In this paper , a single-index partially functional linear quantile regression is proposed, and B-splines are used to estimate the unknown link function and unknown slope function in the single index component and the unknown linear component, respectively.
Journal ArticleDOI

Curve Fitting Algorithm of Functional Radiation-Response Data Using Bayesian Hierarchical Gaussian Process Regression Model

TL;DR: In this paper , a nonparametric Bayesian hierarchical (NBH) model and a variational approximation (VA) algorithm for the curve fitting of the functional radiation response data are presented.
Journal ArticleDOI

Bi-Smoothed Functional Independent Component Analysis for EEG Artifact Removal

TL;DR: In this article, the spectral decomposition of the kurtosis operator of a smoothed principal component expansion is used to obtain the smoothed basis for the independent component model, and a discrete roughness penalty is introduced in the orthonormality constraint of the covariance eigenfunctions.
References
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Dynamic programming algorithm optimization for spoken word recognition

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Generalized Additive Models

TL;DR: The class of generalized additive models is introduced, which replaces the linear form E fjXj by a sum of smooth functions E sj(Xj), and has the advantage of being completely auto- matic, i.e., no "detective work" is needed on the part of the statistician.