Definition
Plain language
The little range around a reported number showing how much it might wobble if you measured again.
As stated in the literature
A visual or numeric representation of estimate uncertainty (standard deviation, standard error, or confidence interval); single-seed results carry none, so differences of a few points may be path dependence rather than signal.
Also called: error bar
Why it matters: Without them, small gaps between systems look like real differences when they may just be luck, which quietly corrupts every leaderboard built on them.
For example, reporting a score as "72, give or take 5" tells you that a rival scoring 74 might not actually be better.
Heard on the show
“The Arena has no error bars at all.”Episode 245 — Fifteen Models Ran Football Clubs for Twenty Years, and Size Didn't Decide It