Question 1

What is a trading edge in simple terms?

Accepted Answer

A trading edge is a measurable reason to expect a positive result over many trades after costs. It is not a promise about any single trade, just a small statistical advantage that shows up across a large sample.

Question 2

What is expectancy?

Accepted Answer

Expectancy is the average amount you would expect to win or lose per trade over the long run. It combines how often you win with how big the wins and losses are, so it is more honest than win rate alone.

Question 3

Why does variance make it hard to know if an edge is real?

Accepted Answer

Variance is the random swing in results from trade to trade. Over a small number of trades, that swing can be larger than the edge itself, so a real edge can look like a loser and a lucky run can look like skill. Only a large sample starts to separate the two.