Maximum Likelihood Estimation for k-Out-of-n System Data R package kofn version 0.4.0 Maximum likelihood estimation of component lifetime parameters from system-level observations of k-out-of-n systems. Supports exponential and Weibull component distributions under multiple observation schemes: Scheme 0 (system lifetime only), Scheme 1 (periodic inspection), and Scheme 2 (complete monitoring). Provides an EM algorithm for Weibull parallel systems and Fisher information comparison across schemes. The k-out-of-n framework unifies series (k=1) and parallel (k=m) systems as a censoring problem on component lifetimes. Conforms to the 'likelihood.model' generics and returns fitted objects compatible with 'algebraic.mle'. The data-generating process and topology infrastructure (system survival, density, signature, structure function, importance measures) are delegated to the 'dist.structure' package; 'kofn' focuses exclusively on inference for the k-out-of-n family. Software Depends: R (>= 4.1.0) Imports: stats, numDeriv, likelihood.model, compositional.mle, generics, dist.structure, algebraic.dist, flexhaz (>= 0.5.2) Suggests: algebraic.mle, maskedcauses, testthat (>= 3.0.0), knitr, rmarkdown Alexander Towell <lex@metafunctor.com> Comprehensive R Archive Network (CRAN) Alexander Towell [aut, cre] (ORCID: <https://orcid.org/0000-0001-6443-9897>) MIT + file LICENSE (https://CRAN.R-project.org/package=kofn/LICENSE) 2026-06-19 application/tgz https://CRAN.R-project.org/package=kofn doi:10.32614/CRAN.package.kofn