Does positive expectancy mean I will definitely make money?

No. Expectancy is only an average of past records and does not guarantee the next trade. Even when positive, you can hit a losing streak over a short stretch, and if market conditions change, the past average may not continue. Use it as a trend over a large sample, not as a forecast.

How does expectancy differ from payoff ratio?

Payoff ratio looks only at the size ratio of average win to average loss and ignores win rate. Expectancy multiplies in win rate and loss rate too, showing the average result you can expect per trade. In other words, expectancy is the composite figure that captures both win rate and payoff ratio.

Expectancy: Your Average Expected Result Per Trade

Expectancy is the average result you can expect from a single trade. You calculate it as (win rate × average win) − (loss rate × average loss), folding win rate and payoff ratio into one number. A positive expectancy means your approach leans positive over the long run; a negative one signals it leans the other way.

How to Calculate Expectancy

Expectancy = (win rate × average win) − (loss rate × average loss). For example, with a 50% win rate, an average win of +$200, and an average loss of -$100, you get (0.5 × 200) − (0.5 × 100) = +$50. That means you expect about $50 on average per trade. Even with a low win rate, expectancy can be positive when the average win is large enough relative to the average loss.

How to Use Expectancy

Expectancy bundles win rate, payoff ratio, and trade frequency to show which direction your approach leans over the long run. When positive, cumulative results tend toward profit as the sample grows. But this is only an average summarizing past records, it cannot predict the next single result and does not guarantee the future. With few trades, expectancy itself swings heavily on chance.

Viewing Expectancy in I See Stocks

I See Stocks calculates expectancy per trade automatically from your logged win rate and average results, showing it on one screen with win rate, payoff ratio, and profit factor. Break expectancy down by buy-reason tag and you can confirm, as fact, which reasons performed better on average. This value summarizes past data only and recommends no stocks or trades.

FAQ

Does positive expectancy mean I will definitely make money?: No. Expectancy is only an average of past records and does not guarantee the next trade. Even when positive, you can hit a losing streak over a short stretch, and if market conditions change, the past average may not continue. Use it as a trend over a large sample, not as a forecast.
How does expectancy differ from payoff ratio?: Payoff ratio looks only at the size ratio of average win to average loss and ignores win rate. Expectancy multiplies in win rate and loss rate too, showing the average result you can expect per trade. In other words, expectancy is the composite figure that captures both win rate and payoff ratio.

Related terms

Author's own past trade · Informational only, not investment advice or a recommendation · Self-reported, unverified