What about life span (instead of time frame) of trade assuming your bet is small with no stop loss (meaning you can let it go against for a wide max pain point)? If you trade both long and short positions, then at some point in time an opportunity will present itself to profit. it may be one day or 10 years
Ok, you have an idea, a feeling, a simple or complex indicator that tells you to enter a trade.
Whatever the reason is you can test its validity by checking MFE (maximum favorable excursion) and MAE (maximum adverse excursion) results. You can create almost unlimited time or volume segmentations to test over - 1 minute, 1 hour, 1 day, 1 week, 1 month, etc or via volume/shares traded.
Favorable moves vs adverse moves from your entrance need to be statistically significant across some time or volume traded period otherwise your entrance signal is just random.
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