# ggplotting power curves from simr package

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The R package `simr`

has greatly facilitated power analysis for mixed-effects models using Monte Carlo simulation (i.e., hundreds or thousands of tests under slight variations of the data). The `powerCurve`

function is used to estimate the statistical power for various sample sizes in one go. Since it runs serially, it can take a VERY long time to finish; approximately, the time it takes to run the model supplied once (say, a few hours) *times* the number of simulations (`nsim`

, which should be higher than 200) *times* the number of different sample sizes examined. While there isn’t a built-in parallel method, the power curves for different sample size can be run separately, and the results can be combined (see tutorial). The power curves produced by `simr`

are so good they deserve `ggplot2`

rendering. So, here’s a function for it.