Semi-Parametric Shape-Restricted Fixed/Mixed Effect(s) Regression Spline R package SRMERS version 0.1.1 Select the most suitable shape to describe the relationship between the exposure and the outcome among increasing, decreasing, convex, and concave shapes (Yin et al. (2021) <DOI:10.1007/s13571-020-00246-7>); estimate the direct and indirect effects with prior knowledge on the relationship between the mediator and the outcome with binary exposure (Yin et al. (2024) <DOI:10.1007/s13571-024-00336-w>); estimate the direct and indirect effects using linear regression-based approach (VanderWeele (2015, ISBN:9780199325870)). Software Depends: R (>= 4.4.0) Imports: splines2, stats, lme4, nloptr, dplyr, MASS, coneproj, Matrix Suggests: knitr, rmarkdown, testthat (>= 3.0.0) Qing Yin <qiy25@pitt.edu> Comprehensive R Archive Network (CRAN) Qing Yin [aut, cre], Shyamal Das Peddada [aut], Jennifer Joan Adibi [aut], Jong-Hyeon Jeong [aut] GPL-3 2026-01-13 application/tgz https://CRAN.R-project.org/package=SRMERS doi:10.32614/CRAN.package.SRMERS