Quote from ssrrkk:
I am not so sure about this. Let's say you ran 1000 OOS tests while optimizing a parameter in your system. Out of those 1000, I think you can still expect around 100 of them to make money due to shear chance. Again, if your performance metric is significant beyond p<0.05, then you have slightly more confidence, I think.
Instead, say you ran just 1 OOS test having optimized your system In Sample, and that your OOS test produces 100x as many trades as In Sample.
If that 1 and only OOS test produced performance as good as in Sample, that would be a good sign, no?
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