Package: mGSFPCA
Title: Estimate Functional Principal Components from Sparse Data
Version: 0.2.2
Authors@R: 
    c(person("Uche", "Mbaka", , "uche.mbaka@ucd.ie", role = c("aut", "cre"),
           comment = c(ORCID = "0000-0002-1427-6388")), 
      person("Michelle", "Carey", , "michelle.carey@ucd.ie", role = "ctb",
            comment = c(ORCID = "0000-0002-5603-4264"))
      )
Description: Implements functional principal component analysis (FPCA)
        for univariate and multivariate sparse functional data. The
        package estimates eigenfunctions, eigenvalues, and error
        variance simultaneously via maximum likelihood estimation
        (MLE), using a spline basis representation of the
        eigenfunctions. Orthonormality of the estimated eigenfunctions
        is enforced through a modified Gram-Schmidt (MGS)
        orthogonalization procedure applied iteratively during
        estimation, avoiding direct optimization over the Stiefel
        manifold and improving numerical stability. The optimal number
        of basis functions and principal components is selected via an
        Akaike Information Criterion (AIC)-type criterion, supporting
        both a full grid-search strategy and a computationally
        efficient sequential selection approach. Principal component
        scores are estimated by conditional expectation, enabling
        reconstruction of individual trajectories over the entire
        domain from sparse observations. Pointwise confidence intervals
        for reconstructed trajectories are also provided. Methods are
        described in Mbaka, Cao and Carey (2026)
        <doi:10.48550/arXiv.2603.18833> and Mbaka and Carey (2026)
        <doi:10.48550/arXiv.2603.19799>.
License: GPL (>= 3)
Encoding: UTF-8
RoxygenNote: 7.3.2
Depends: R (>= 2.10)
LazyData: true
Imports: fda, pracma, Rcpp, Metrics
LinkingTo: Rcpp, RcppEigen
NeedsCompilation: yes
Packaged: 2026-05-08 17:25:22 UTC; root
Author: Uche Mbaka [aut, cre] (ORCID:
        <https://orcid.org/0000-0002-1427-6388>), Michelle Carey [ctb]
        (ORCID: <https://orcid.org/0000-0002-5603-4264>)
Maintainer: Uche Mbaka <uche.mbaka@ucd.ie>
Repository: https://cran.r-universe.dev
Date/Publication: 2026-05-08 15:55:54 UTC
RemoteUrl: https://github.com/cran/mGSFPCA
RemoteRef: HEAD
RemoteSha: b0f47c5c46647074f2c61fc11ef4a419d780c030