Package: powerutilities
Title: Power Analysis for Linear and Generalized Linear Mixed Models
Description: Prospective power analysis and design planning using the
        "plug-in" approach described by Piepho et al. (2022)
        <doi:10.1017/S0021859622000466> and Stroup, Ptukhina and Garai
        (2024) <doi:10.1201/9780429092060-24>. Expected treatment means
        and the proposed experimental design are encoded in an
        artificial data set, and a model is "fit" to it with random
        effect variances, correlations and residual dispersion fixed at
        user-specified values rather than being estimated. The
        resulting standard errors are used to compute the power of
        F-tests and user-defined contrasts, as well as Type S (sign)
        and Type M (magnitude) error rates (Gelman and Carlin, 2014
        <doi:10.1177/1745691614551642>). Models are fit with 'glmmTMB',
        so the approach accommodates non-normal responses,
        heteroscedasticity, nested and crossed random effects,
        correlated random slopes, and structured covariances such as
        AR(1) and spatial correlation. Helper functions convert
        standard deviations and correlations into the internal
        parameterization of 'glmmTMB' and report the order in which
        random effect parameters must be supplied. Denominator degrees
        of freedom can be computed by the Kenward-Roger, residual or
        asymptotic methods (or can be specified by users), and
        contrasts are specified through 'emmeans'. Vignettes cover
        estimated marginal means, contrast specification, and worked
        examples for common agricultural designs.
Version: 0.7.1
Authors@R: 
    person("Simon", "Riley", email = "ssriley@protonmail.com", role = c("aut", "cre"), comment = c(ORCID = "0000-0002-4833-2026"))
Depends: R (>= 4.1.0)
Imports: dplyr, emmeans, glmmTMB (>= 1.1.14), pbkrtest,
        reformulas,retrodesign, rlang
Suggests: agridat, knitr, rmarkdown, testthat (>= 3.0.0), tidyr
License: BSD_3_clause + file LICENSE
URL: https://github.com/SimonShamusRiley/powerutilities/tree/main
BugReports: https://github.com/SimonShamusRiley/powerutilities/issues
Encoding: UTF-8
Roxygen: list(markdown = TRUE)
VignetteBuilder: knitr
LazyData: true
Config/roxygen2/version: 8.1.0
Config/testthat/edition: 3
Config/pak/sysreqs: cmake make libicu-dev
Repository: https://simonshamusriley.r-universe.dev
Date/Publication: 2026-10-13 08:13:06 UTC
RemoteUrl: https://github.com/simonshamusriley/powerutilities
RemoteRef: HEAD
RemoteSha: 1cc2ac973428ccb02fb5e07cfa275a0326813e95
NeedsCompilation: no
Packaged: 2026-10-22 10:18:10 UTC; root
Author: Simon Riley [aut, cre] (ORCID: <https://orcid.org/0000-0002-4833-2026>)
Maintainer: Simon Riley <ssriley@protonmail.com>