NO is a measure of how long in N's it takes you to win 1 std dev on avg. N is whatever you use (100 hands, hours, etc) also, 4(NO)= 2 std dev. and 9(NO) = 3 std dev., etc.
it's a cool figure, but i don't really understand it, so i mihgt be misrepresenting this some. go to
http://forums.cardplayer.com/viewtop...;postorder=asc
for more links and details about some of the formulas used.