http://www.nasdaq.com/symbol/uso/option-chain It's fairly liquid and widely held (high OIs for near the money options). Also the calculation is using midpoint of Bid/Ask, and as long as bid/ask are comparatively OK (otherwise arbs will step in), the IV should not be way too off.
IMHO: I have not tried to analyze IV intraday, so may be missing something important. However, I think what you are observing should be expected behavior. Note: the diversion is mean reverting seeming to merely indicate the buying/selling pressure is not instantaneously uniform (you would not expect it to be), but is likely closely uniform over longer duration. May indicate either buying or selling pressure at a specific strike that subsequently seems to also appear in other strikes and expirations. It may be more visible if you produce a complete volatility surface including the expirations of interest, and observe the outliers to correlate to the graphs you are producing. This should help to pinpoint the source.
Hi stepandfetchit I understand what you mean by reversion to mean, but the way the two ratios are moving in opposite direction, may be something unique to USO. I have not seen it in other ETFs of different assets (such as TLT, GLD, SPY, etc). Regarding the complete volatility surface plot, I will probably need some work on my side, as I dont have the infrastructure to do that. Hopefully in the weekend.
So I can't even plot the 15 day vol properly, but it does look that you've observed some sort of a persistent movement, as the 1M vol outperforms both the short-dated and the 3M vol over the recent few days. I really don't know what might be behind it, although I can see that the 1M vol was also the relatively "beaten down" one prior to the recent moves.
I see your point about the USO IV30 itself. I can see it's sitting at a 3 month low. It has been beaten down a lot (this is google chart of OVX index for 3 months). Also attaching the chart from May 11 onwards, which shows how the OVX has spiked up both days, which may have caused the behavior I observed.
So, like I mentioned, I can't plot the shorter-dated vol properly, but at least you can observe what seems like a move in the 1M vs 3M since the 10th.
So the spread is all over the place, from +1 to -1 and now again 0.5. Ideally, the spread should be negative (1M-3M) since 3M vol is usually higher than 1M vol. But oil being so volatile, I guess people are taking bets all over the place.
Well, there's definitely some directional component to this vol spread, as you can see from the long-term plot. Not sure what specific conclusion you may be able to draw from it.
I am more looking from intraday point of view in short term to take some sort of swing trades based on how different IVs are moving. Normally, IV Short/Term rises when the underlying is falling and vice versa. But looks like oil behaves differently.