The precision starts with, how the systems analysis potential trades.

 

Before a trade can be taken place, there must be a signal.

 

The system differs between a open to buy signal and open to execute signal.

 

Before an actual trade execution can taken place, the buy a signal has to be appeared.

 

In practice, the system analysis in the back test window the data do a certain date. If at this date a signal is generated, the underlying security is then bought at the next open.