Stop

Written in advance, this is the condition that ends the inquiry: the date, sample size, or spend at which you quit collecting and decide with what you have. It also names what would reopen the question later.

Written in advance, this is the condition that ends the inquiry: the date, sample size, or spend at which you quit collecting and decide with what you have. It also names what would reopen the question later.

Example

"We read the number once, on March 31, at 8,000 signups, and decide that day. No extra month, no second cut of the data. We reopen only if a later cohort drops below the 4 percent floor for two straight months."