A team rated four points better than its opponent does not cover a 3.5-point spread four times out of five, or even close. Turning a rating into NFL cover probability takes one more step: a distribution of possible margins. This lesson walks that step, then sets the result next to the break-even rate at -110 so you can tell whether a price has value or just looks friendly. Along the way you meet the problem with smooth bell curves in a sport where games land on 3 and 7 all the time, and why pushes on whole-number spreads need their own estimate. Expect to leave knowing how to question your own number before you trust it with money.
Learning objectives
Explain the technique, compute the illustrative example, test assumptions, and identify failure modes.
