Quote from Rationalize:
Back testing is absolutely necessary for debugging, & back testing can be useful when used correctly, for verifying stat arb strategies.
Stats arb is primary application of back-testing.
When doing INITIAL BACKTESTING of stats arb...
One simplifies, simplifies, simplifies...
I use ETFs, not Forex/futures ticks, at first...
To look at basic correlations.
Once you are actually trading...
One can optimize with more detailed data.
It's ALL ABOUT EXECUTION anyway...
Your strategy is 10% of equation...
EXECUTION is 90% of equation.
And the whole idea of tick data and bars...
Is a sinister invention to sell you shit for $$$...
Imagine if your doctor divided your life into 5 min bars...
You would think he's insane...
Just like the people who divide the market into 5 min bars.
It's a fucking continuum.