From this post https://www.projectoption.com/expected-move-explained/, he uses the following formula to calculate a 1 SD move in the stock:
How do you know which stock option to use for this?
For example, if I want to calculate the expected move in SPX for Feb expiration, what do I use?
SPX is at 2616. Do I use puts or calls?
If puts, should it be 2615 OTM or 2620 ITM? Same question if with calls.
For strikes that are next to each other, it probably doesn't matter which I use, since IVs will be very close. At least for SPX. There could be a bigger difference in IVs for other stocks.
Can someone provide a completed calculation?