Model Free Approach to Quantifying Surrogacy R package OptimalSurrogate version 1.0 Identifies an optimal transformation of a surrogate marker such that the proportion of treatment effect explained can be inferred based on the transformation of the surrogate and nonparametrically estimates two model-free quantities of this proportion. Details are described in Wang et al (2020) <doi:10.1093/biomet/asz065>. Software Depends: R (>= 3.0) Imports: splines, MASS, stats Layla Parast <parast@austin.utexas.edu> Comprehensive R Archive Network (CRAN) Xuan Wang [aut], Layla Parast [aut, cre], Ming Yang [aut], Lu Tian [aut], Tianxi Cai [aut] GPL-3 2022-09-27 application/tgz https://CRAN.R-project.org/package=OptimalSurrogate doi:10.32614/CRAN.package.OptimalSurrogate