Package: MultiSpline
Type: Package
Title: Spline-Based Nonlinear Modeling for Multilevel and Longitudinal
        Data
Version: 0.3.0
Authors@R: person(given = "Subir",
                  family = "Hait",
                  email = "haitsubi@msu.edu",
                  role = c("aut", "cre"),
                  comment = c(ORCID = "0009-0004-9871-9677"))
Description: Provides a unified framework for fitting, predicting, and
    interpreting nonlinear relationships in single-level, multilevel, and
    longitudinal regression models. Flexible functional forms are supported
    using natural cubic splines ('splines'), B-splines ('splines'), and GAM
    smooths ('mgcv'). Supports two-way and nested clustering via 'lme4',
    automatic knot selection by AIC or BIC, multilevel R-squared
    decomposition (marginal and conditional R-squared of Nakagawa and
    Schielzeth (2013) <doi:10.1111/j.2041-210x.2012.00261.x>, extended to
    random slopes as in Johnson (2014) <doi:10.1111/2041-210X.12225>, with
    level-specific variance partitioning), a postestimation suite
    returning first and second derivatives with confidence bands, turning
    points and inflection regions, and a model comparison workflow
    contrasting linear, polynomial, and spline fits by AIC, BIC, and
    likelihood-ratio tests. Cluster heterogeneity in nonlinear effects is
    supported via random-slope spline terms. Any 'lme4' random-effects
    structure can be supplied, and population-averaged (marginal) curves
    are available for generalized linear mixed models.
Depends: R (>= 4.2.0)
Imports: stats, lme4, mgcv, dplyr, ggplot2, rlang, splines
Suggests: lmerTest, knitr, rmarkdown, reformulas, numDeriv, patchwork,
        testthat (>= 3.0.0)
Config/testthat/edition: 3
License: GPL-3
Encoding: UTF-8
Language: en-US
URL: https://github.com/subirhait/MultiSpline
BugReports: https://github.com/subirhait/MultiSpline/issues
NeedsCompilation: no
Packaged: 2026-10-11 00:38:59 UTC; subir
Author: Subir Hait [aut, cre] (ORCID: <https://orcid.org/0009-0004-9871-9677>)
Maintainer: Subir Hait <haitsubi@msu.edu>
Config/roxygen2/version: 8.0.0
Repository: CRAN
Date/Publication: 2026-10-11 02:30:02 UTC
