What is edge in trading?
Edge is a real, nameable gap between what something is worth and what the market charges for it. The market says 61¢; your work says the true odds are closer to 68¢. That 7-point gap, and the reason behind it, is edge. Without it there is no bet: the fund never bets a price it believes is fair.
Why “nameable” is the key word
A feeling that a price is wrong isn't edge, it's mood. Edge has a sentence attached: “the crowd is overreacting to one injury report,” “this market hasn't priced yesterday's ruling,” “my Barcelona model has beaten this line all season.” If the reason can't be named, your CEO treats the gap as noise and passes.
Edge is the whole business
Betting at fair prices is entertainment, over time, fees guarantee you lose slowly. Betting only where you hold a real edge is the entire difference between a fund and a casino patron. It's also why most of your CEO's work ends in a pass: real edges are scarce, and pretending otherwise is how bankrolls die.
From edge to bet size
Edge isn't just permission to bet, it's the input to how much. A wide, well-evidenced gap earns a fuller position; a thin one earns a small bet or none, once fees take their bite. Size follows edge, never excitement.