StavrosK, I'm delighted to see you post this; I was hoping you'd do so! If people are interested in calculating the sample size before running an A/B test, I'd

StavrosK, I'm delighted to see you post this; I was hoping you'd do so! If people are interested in calculating the sample size before running an A/B test, I'd recommend tools such as the following (to which I have no connection): http://www.danielsoper.com/statcalc/calc01.aspx http://www.danielsoper.com/statcalc/calc01.aspx