Thinking Stuff's ATM

Automated Trading Machine (ATM) makes it simple to remove fear and greed from your trading. Automated trading is no longer just for the rich or nerdy. Our revolutionary software runs on your computer, using your trading rules, but none of your emotions. There's just one requirement - you know how to use a mouse.  Learn more...

Thinking Stuff's ATE

Automated Trading Execution (ATE) is where we run your trading systems for you on our servers. Your system can be exported from ATM, or written in plain English and we'll make it for you. We'll even backtest and suggest improvements if you want us to. This service essentially automates your automated trading.  Learn more...

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PWB#6 - The Forward Look

I heard a common mistake when creating a backtesting program, is to use the close price of a bar for decision making during that same bar.

The problem is, until that bar is finished, you don't know what the close price will be. You know it while backtesting because it's historical data. But not in real-time trading, and real-time trading is what backtesting is trying to emulate.

And it might not be so obvious that this is going on. If you're explicitly using the close price, then sure, it's obvious. But if you're using an indicator value that is calculated from the close, you might not realise.

Anything related to the close of the bar, can only be acted upon in the next bar.

Thanks to Trader Eyal for this one.