has anyone done a study to find which stocks/etfs/futures usually have realized - implied greater than 0? For example, low beta stocks usually have much higher IV than what is realized.
Not a hard study to do, but for equites, you have to decide what data to use. Do you include just before and after events like earning and other binary events?
Here is a simple TOS study that compares the 30-day. "http://tos.mx/bSxZQr"
A slow moving average of the difference is provided with the actual data.