Probe

The specific observation you commit to making before you look: what gets measured, on whom, over what window, by what method. It has to be able to tell your claim apart from the rival, not merely confirm the claim.

The specific observation you commit to making before you look: what gets measured, on whom, over what window, by what method. It has to be able to tell your claim apart from the rival, not merely confirm the claim.

Example

For the newsletter: the next four sends get split 50/50 between short and long subject lines, and opens are counted only among the 6,200 readers who subscribed before the podcast aired, so the traffic wave cannot inflate either arm.