Package: stagelife
Type: Package
Title: Random Number Generation and Inferences for Two-Stage
        Life-Testing Data
Version: 0.1.0
Authors@R: person("Vikas Kumar", "Sharma", email = "vksharma@bhu.ac.in", role = c("aut", "cre"))
Description: Provides random number generation, estimation, and hypothesis
    testing for two-stage life-testing experiments in which units begin on
    a baseline stress and, at a fixed or random change point, some or all
    surviving units move to an elevated stress ("stage life testing"),
    following the cumulative-exposure model of Laumen and Cramer (2019),
    "Stage life testing", <doi:10.1002/nav.21874>. Twelve baseline lifetime
    distributions are supplied (Weibull, Power Lindley, Exponentiated Lindley,
    Exponentiated Exponential, Marshall-Olkin Exponential, Lomax,
    Exponentiated Teissier, Log-Logistic, Chen, Log-normal, Gamma, and Power
    Muth/Power Teissier) together with three parameter-sharing cases
    (common, shape1, shape11). The package implements data simulation
    under both the fixed-proportion (typeP) and fixed-count (typeM) rules
    and the simple-step-stress special case, maximum likelihood estimation
    using a hybrid Nelder-Mead and BFGS optimisation routine, asymptotic
    (Wald) and non-parametric/parametric bootstrap confidence
    intervals (including log-scale variants that guarantee a positive
    interval), a stage-1-observation planning probability, Kolmogorov-Smirnov
    goodness-of-fit testing with a parametric-bootstrap correction for
    estimated parameters, likelihood-ratio and information criteria for
    nested/non-nested model comparison, and diagnostic plots comparing
    fitted and empirical distributions, including the cumulative
    distribution function (CDF), survival function, probability-probability
    (P-P), and quantile-quantile (Q-Q) plots.
License: MIT + file LICENSE
Encoding: UTF-8
LazyData: true
Depends: R (>= 4.1.0)
Imports: compiler, ggplot2, graphics, lamW, parallel, stats
Suggests: knitr, rmarkdown, testthat (>= 3.0.0)
VignetteBuilder: knitr
Config/testthat/edition: 3
URL: https://github.com/vksharma-bhu/stagelife
BugReports: https://github.com/vksharma-bhu/stagelife/issues
Config/roxygen2/version: 8.1.0
NeedsCompilation: no
Packaged: 2026-10-16 16:05:32 UTC; root
Author: Vikas Kumar Sharma [aut, cre]
Maintainer: Vikas Kumar Sharma <vksharma@bhu.ac.in>
Repository: CRAN
Date/Publication: 2026-11-03 12:00:02 UTC
