hard20 pts · first answer countsexperimentationstatistics
How long will the test take
Baseline conversion is 5%. You want to detect a 10% relative lift (5.0% to 5.5%) with about 80% power at 5% significance. A rule of thumb gives n per variant = 16 x p(1 - p) / delta squared. Your page gets 2,000 visitors a day split evenly. About how long must the test run?