Trading Edge: Expectancy, Probability and Luck

A trading edge is the one thing every trader claims and few can show. It means a positive expected result per trade, after costs, that persists. Whether you have one cannot be settled by how confident you feel or by last month’s results; it is settled by a record and some arithmetic.

How do you calculate a trading edge?

Expectancy is the average result per trade: the win rate times the average win, less the loss rate times the average loss, less costs. A method that wins 40% of the time can have a large edge; one that wins 80% can have none. The course has you calculate it for real records and for your own.

How can you tell skill from luck in trading?

By asking how likely the record would be if there were no edge at all. The course answers that by simulation in a spreadsheet, so you can see how often pure chance produces a record as good as the one in front of you. Most students find it is more often than they thought.

Who is this course for?

Every trader on the trader path. It is the basis of Evidence-Based Trading in the second semester. No programming is needed.

What you will be able to do

• Calculate the expectancy of a method from its win rate, average win, average loss and costs.
• Estimate how many trades are needed before a record says anything about an edge.
• Simulate losing streaks and drawdowns in a spreadsheet.
• Recognise survivorship, selection and hindsight in trading claims.

Syllabus, module by module

1. Expectancy

   Average result per trade, after costs, from win rate and payoff.

2. Probability without formulas

   Coin flips, dice and card draws as models for trading results, built in a spreadsheet.

3. Variance and streaks

   How far a real record wanders from its expectancy, and how long bad runs last.

4. Sample size

   How many trades it takes to tell an edge from luck, with a rule of thumb you can use.

5. Luck dressed as skill

   Survivorship, cherry-picked records, and the trader who was right three times.

6. Where edges come from

   Risk premia, behaviour, information, speed and structure, and which are open to an individual.

How the certificate is earned

Weekly quizzes and two graded problem sets: an expectancy and sample-size analysis of a published trading record, and a spreadsheet simulation of your own method. On a pass you receive the Course certificate in Trading Edge, issued by the Institute with a verification code. Read how certification works.