COMMENT "QUANT"
Win rate is a trap: test before you trust ($10k to $10,770)
A strategy won 11 of 15 trades, a 73% win rate, and still barely finished up, because one bad trade cut it almost in half along the way. The lesson: a high win rate means nothing if your losers are huge. What matters is the worst drop (the drawdown). Here's how to test any strategy for free before risking a dollar. Most people lose money trading, so this is not financial advice.
01Quick steps
- 1Free tool: github.com/vnpy/vnpy (vn.py).
- 2Test your idea on past data before any real money.
- 3Look at the WORST drop it ever had, not the win rate.
- 4A smaller worst-drop beats a higher win rate almost every time.
02Your ready to use prompt
I ran a trading strategy and got these results: [paste win rate, final balance, and max drawdown]. In plain English, is this strategy actually good or just lucky? Focus on the worst drawdown, not the win rate, and tell me the single biggest weakness.
03Full tutorial
A 73% win rate looks amazing, but if the few losses are huge, the account still bleeds. The number everyone brags about hides the real risk.
vn.py (github.com/vnpy/vnpy) is a free, open-source platform with about 46,000 stars that lets you test a strategy on years of past data.
Follow the repo's setup guide to install vn.py on your computer (it runs on Python). The README walks through it step by step.
Point it at historical price data for the market you care about, so it can replay what would have happened.
This is called backtesting: the tool plays your rules against the past and shows every trade it would have made.
Find the max drawdown, the worst drop from a high point. If a 'winning' strategy nearly got cut in half, it's fragile and will scare or wipe you out in real life.
Between two strategies, the one with the smaller worst-drop usually wins long term, even with a lower win rate.
Once a strategy survives the past, run it on fake money live for a few weeks before you ever risk a real dollar.
A screenshot of wins tells you almost nothing. Judge a strategy by its worst drop. Not financial advice.