Lesson
Doubling down
By Thomas Jamais (Backtestd) · Published · Updated
In short
Doubling down instead of taking the stop raised the win rate from 33% to 46%.
But profit per trade fell from plus 0.16 R to plus 0.02 R. You win more often, but you earn less.
A win rate tells you how often you win, not what one loss costs.
The numbers
| Group | Value |
|---|---|
| Take the stop · Win rate | 33% |
| Double down · Win rate | 46% |
| Take the stop · R per trade | +0.160 R |
| Double down · R per trade | +0.020 R |
How we measured it
Every number comes from the lab's database: — strategy versions with at least 100 trades each, tested on crypto perpetual futures from 2022 to 2025 with fees, slippage and funding. One version = one strategy with one set of settings. Results are in R (the amount risked per trade).
What to do instead
- Decide the maximum loss of a trade before you enter, and keep it.
- Judge a method by its result per trade (in R), not its win rate.
- Look at the worst loss, not the average: one doubled loss can erase months.
Verify it yourself
- Write the rule exactly (below: our specification and every setting we tried).
- Get free data: Binance's public archive (data.binance.vision) has years of candles; OKX and most exchanges offer an API.
- Include costs: fees on both sides, slippage, and funding for perpetual futures.
- Count results in R (risk per trade), not in %, and look at the typical version, not the best one.
- Split your data in two and keep a part you never look at until the end.
- Compare with simply holding the market over the same days.
Disclaimer
Educational content based on historical backtests. Not financial advice. Past results do not predict future results. Trading leveraged products can lose more than you invest.