edeltapro is one the few websites that offer options backtesting. you want to act like a twat, get treated like a twat
Abnormal Skew in Delta/Prob of OTM
- Thread starter Atikon
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edeltapro is one the few websites that offer options backtesting. you want to act like a twat, get treated like a twat
You are the one asking an incoherent question.
TOS uses a proprietary formula for Prob of ITM..
FWIW.After a 2 second look,it appears that TOS is relatively consistent in their inconsistencys vs Delta...Look at the respective Delta options(put vs call),and you will see a pattern
Not sure why you care,its simply some proprietary gobbly gook they cam up with
FWIW.After a 2 second look,it appears that TOS is relatively consistent in their inconsistencys vs Delta...Look at the respective Delta options(put vs call),and you will see a pattern
Not sure why you care,its simply some proprietary gobbly gook they cam up with
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It looks like their probability model wasn't built to deal with extremely high IV where you could be seeing:
1) A binary event with minimal skew.
2) very high priced wings relative to the ATM.
Just throwing out some guesses. Try a few more and look at how flat the skew is. Tell us what you find.
1) A binary event with minimal skew.
2) very high priced wings relative to the ATM.
Just throwing out some guesses. Try a few more and look at how flat the skew is. Tell us what you find.
It looks like their probability model wasn't built to deal with extremely high IV where you could be seeing:
1) A binary event with minimal skew.
2) very high priced wings relative to the ATM.
Just throwing out some guesses. Try a few more and look at how flat the skew is. See how it calculates with the commodity etfs with a call skew. Tell us what you find.
1) A binary event with minimal skew.
2) very high priced wings relative to the ATM.
Just throwing out some guesses. Try a few more and look at how flat the skew is. See how it calculates with the commodity etfs with a call skew. Tell us what you find.
So Mistery solved! Heavily scewed Distribution to the downside/right-scewed. The PD is a Implied Probability Density in TOS/derived from Price Action. The other effect is that PD of the Normal Distribution has a fatter tail to the Call Side since the possible upside is unlimited and the Put Side is limited to 0/max loss of -100%. The Call Side effect is exaggerated through higher Implied Volatility. The higher the IV/Std deviation gets, the flatter the Probability Distribution ->the fatter the tails. Since Delta is calculated based on a normal distribution it will have a lot of cum Probability at 0.3 Delta on the Call Side, when the implied PD thinks the true PD/true value is more on the Put Side, hence 0.3 Delta will have a high OTM Prob and vice versa for Put 0.3 Delta
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Nah it's good thinking, I was a bit cofused since both sides had the same Implied Volatility. They (Exchanges) Derive the Probability Density Function from Price Action but calculate the Delta based on a Lognormal Distribution. High IV made it worse.
Look at d1 with a 123% IV and d1 with a 30% IV for AXSM (Price was around 64USD today) and you will see the difference Implied Volatility made in the tails. High IV pushed the Call Delta even further out, taking even more Probability under its wing.
At IV of 30% the slope is steeper, the delta is closer to the ideal Normal Distribution and hence it is possible to approximate it via the Delta. Now if the PD is derived through the market when we just went for a drawdown of 35% the distribution becomes right scewed/ppl are more fearful and think the stock is going to tank. So a 0,30 Delta will have more Probability cought at it's Strike price, since more than 50% of the Probability is located at the Put Side.
The IV pushes the Delta out (look at Delta IV 30%, Delta 0.3 is at around 67 USD where as at IV 123% Delta 0.3 is at around 83 USD /fat tail effect) which worsens the effect by making the distribution flatter.
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Call side vs Put side doesn't exist...talking in terms of percent of spot makes life alot easier..
hahaha, yeah maybe u right, but I attached this graph so I thought it would make more sense that way
