SIMR: an R package for power analysis of generalized linear mixed models by simulation

• Published in: Methods in ecology and evolution Vol. 7; no. 4; pp. 493 - 498
• Main Authors: Green, Peter, MacLeod, Catriona J., Nakagawa, Shinichi
• Format: Journal Article
• Language: English
• Published: London John Wiley & Sons, Inc 01-04-2016
• Subjects: Computer simulation; Environmental effects; Environmental monitoring; experimental design; glmm; Learning curves; Monte Carlo; Monte Carlo simulation; random effects; sample size; Statistical models; type II error
• ISSN: 2041-210X; 2041-210X
• DOI: 10.1111/2041-210X.12504

Summary
The r package simr allows users to calculate power for generalized linear mixed models from the lme4 package. The power calculations are based on Monte Carlo simulations.
It includes tools for (i) running a power analysis for a given model and design; and (ii) calculating power curves to assess trade‐offs between power and sample size.
This paper presents a tutorial using a simple example of count data with mixed effects (with structure representative of environmental monitoring data) to guide the user along a gentle learning curve, adding only a few commands or options at a time.