Both theta and IV get decidedly "lumpy" between ~3:30pm and 9:50am, regardless of weekend or not. Does the weekend *increase* this lumpiness? In my *opinion*, yes, but only from observation -- I can't quote you a study -- which would be pretty hard, as it's news events and threat NON-events that all get balanced.![]()

Did that in '90-'91.
Every Monday - poppin' vol back up. Very un-smooth. Me likey smooth. Built trading day model which treated weekends as 1 day. Much smoother.
Peace!


!!
Heh! Come to think of it, this reminds me of a thread from not too long ago -- maybe since you arrived here at ET, Wheezooo? The general question was how long a year was, for Black Scholes Merton methods, and I gave my vague recollection as 365 if you're an academic, and 252 if you're a practitioner, and that when I built my own stuff, 252 seemed to work with much less questionable outcomes than 365... (If I recall all of this correctly...)