Quote from newwurldmn:
WRONG.
EDIT: Just saw this post, yes that is probably the best idea. Only problem is I can only remodel things down to day by day, I need to know spesifically how gamma changes from minute to minute, this is especially important the last couple hours on friday.Quote from newwurldmn:
why not just remodel the option with a new time to expiry?
Quote from Martinghoul:
Firstly, I would recommend you get this book:
http://www.amazon.com/Complete-Guide-Option-Pricing-Formulas/dp/0071389970
Secondly, if you scroll down in the very same Wikipedia article, you will see the actual formula you're looking for (rather than the definition as a partial derivative, which is what you have above).
Quote from TskTsk:
Im curious if anyone has any formula / paper / etc. that shows how gamma changes with time? I'm trying to run some simple simulations. Say I have 10 options with 0.03 gamma. How will that gamma look in 10 days from now? It will have increased, but how much?
Quote from Kevin Schmit:
A simplified version of the formula, good for "in your head" or back of the envelope calcs is:
-(1-d1*d2)*n(d1)/(2*S*vol)
This assumes zero interest rate, zero dividends, and vol is time adjusted (vol = annualized_vol * sqrt(time)).
The full formula is available in most options texts. However the above is a pretty good approximation for stocks that do not pay dividends.
Edit: for a slightly better approximation substitute the forward price for S