Calculate Sample Size
Use GLIMMPSE to calculate power or sample size. GLIMMPSE is an open-source online tool for calculating power and sample size. It’s been designed so that researchers and scientists with varying levels of statistical training can have access to reliable power and sample size calculations.
Free Sample Size Class
This free online workshop is offered by the University of Florida: Power and Sample Size for Multilevel and Longitudinal Study Designs.
Learn the principles behind sample size calculations with this free online course.