There was no way to know, but in pre market I watch the tension (T) on island (they display the depth of 20 bids and 20 ask, the tension (my own definition) is the difference between the highest bid displayed and the lowest bid displayed divided by the difference between the lowest ask displayed and the highest asked displayed. If T is much larger than 1 and decreasing I sense a turn coming and vice versa. Sometimes, when my other indicators are no "certain", I would use that as a test during the day as well.
Zeev
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