Strategy Expectancy Modeling

Strategy expectancy modeling is the mathematical calculation of the average profit or loss a trader can expect per trade based on historical win rates and the average size of wins versus losses. It provides a statistical framework to determine if a trading system has a positive mathematical edge over the long term.

By multiplying the probability of a win by the average win amount and subtracting the probability of a loss multiplied by the average loss amount, traders can quantify their potential performance. In derivatives trading, this model must also incorporate the probability of extreme events, such as liquidation or flash crashes, which can drastically alter the outcome.

This forward-looking approach allows for better position sizing and risk management, ensuring that the strategy remains sustainable despite inevitable losing streaks.