On NYSE, I have it set at +/-800 and +/-1000. It looks like the Nasdaq extremes are smaller. about +/- 300?
Probably depends on your definition of extreme, I like something in the +770/-720 area. Your correct that the numbers do tend to be less than NYSE. I get those from a 3 min chart and a 3 standard deviation BB.
note also that a tick extreme varies for the day type on a heavy selling day, a positive extreme might be 800, but a negative extreme might be -1100 and vice versa for a strong buying day -1000 and +1000 work well for neutral days also note that tick USED to be slightly positively skewed, but that is largely gone since the elimination of the uptick rule ime these are for NYSE:TICK don't use NASD:TICK so, not sure about that