Data Envelopment Analysis R package DEA version 1.0.0 Nonparametric efficiency measurement by data envelopment analysis. Provides radial (Charnes-Cooper-Rhodes and Banker-Charnes-Cooper) technical efficiency under constant, variable, non-increasing and non-decreasing returns to scale, the slacks-based measure of Tone (2001), the additive model of Charnes and others (1985), and the directional distance function of Chambers, Chung and Fare (1996), all through one interface and one result object. Efficiency estimates are accompanied by peers, slacks, returns-to-scale classification, scale efficiency and the optimal multipliers, and by bias-corrected estimates and confidence intervals from the smoothed homogeneous bootstrap of Simar and Wilson (1998). Where prices are known, cost, revenue and Nerlovian profit efficiency separate the technical component from the allocative one; where they are not, cross-efficiency with the secondary goals of Doyle and Green (1994) ranks units that a self-appraisal leaves tied. This package succeeds the archived 'DEA' package of Diaz-Martinez and Fernandez-Menendez (2008). Software Depends: R (>= 4.0.0) Imports: lpSolveAPI, stats, graphics, utils Suggests: knitr, rmarkdown, testthat (>= 3.0.0), Benchmarking, DJL, parallel, grDevices David Bernstein <davebernstein1@gmail.com> Comprehensive R Archive Network (CRAN) David Bernstein [aut, cre] (ORCID: <https://orcid.org/0000-0002-2267-5741>), Zuleyka Diaz-Martinez [aut], Jose Fernandez-Menendez [aut] GPL (>= 2) 2026-09-10 application/tgz https://CRAN.R-project.org/package=DEA doi:10.32614/CRAN.package.DEA en-US