What does +EV mean in betting
What makes a bet mathematically profitable?
A bet is +EV when the price pays more than the true probability warrants. Fair value 57.34% against a price implying less means the difference is yours, on average, over enough bets.
“On average, over enough bets” is doing heavy lifting. Two things decide whether a printed +EV number is real:
Which devig produced it. The same market reads 57.11% to 57.50% depending on method. If the edge only survives the friendliest one, it is not an edge.
Whether you can get on. Expected value you cannot place is worth zero. A 6% edge at a book that pulls its price in four seconds is worth less than a 3% edge still there when you tap it — which is why a screen ranked on raw EV is ranked partly by how stale its own data is.