How to calculate sample size for an email subject line test with 5 different variants?
Does the number of variants matter? I can do a sample size calculator but I'm not sure if that just works for simple A/B testing.
For example, we have 100k email list. Using this tool: http://www.macorr.com/sample-size-calculator.htm, my sample size is 6373 for 90% confidence with 1% margin of error. Does that mean I send 6373x5 or does that number only work for a 50/50 send?