Quick-R: Power AnalysisFor each of these functions, you enter three of the four quantities (effect size, sample size, significance level, power) and the fourth is calculated. The significance level defaults to 0.05. Therefore, to calculate the significance level, given an effect size, sample size, and power, use the option "sig.level=NULL". Specifying an effect size can be a daunting task. ES formulas and Cohen's sugges
