Spower: A General-Purpose Monte Carlo Simulation Power Analysis Program

This article present the software Spower, an R package designed as a general-purpose, Monte Carlo simulation experiment tool to perform power analyses with a unified API. The package includes complete customization capabilities with support for five distinct (expected) power analysis criteria (prospective/post-hoc, a priori, compromise, sensitivity, and criterion analysis), each of which reports the sampling uncertainty associated with the resulting estimates. Researchers may choose to define their own population generating and analysis function for their tailored simulation experiments, or may choose from a selection of the predefined simulation experiments defined within the package. To facilitate comparability and further extensibility, simulation counterparts of the subroutines from the popular stand-alone software G*Power 3.1 (Faul et al., 2009) are included within the package, along with other simulation experiment subroutines.