The gold standard is to provide a formal power analysis, which determines the sample size required to achieve a pre-specified level of statistical power, given an effect size of interest. One widely-cited review article on this topic is by Maxwell, Kelley, and Rausch (1988), and several book-length treatments of power analysis are also available (e.g., Aberson, 2019, Cohen, 2013). We recognize that power analysis has become more complex in the context of mixed-effects models, often requiring