AlGee57 - I agree. It would seem obvious that the net buy/sell balance is the driving force behind a tick up if the balance was "buying" and a tick down if the balance was "selling".
Beyond that, it is not clear what else can be known. The statistics on day trading success/failure is abysmal and those folks make a vocation of trading on the information "read" from the L2 (among many other factors)...LOL.
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