Quote from ben111:
Hello,
is there any possibility or strategy to profit just from a steepening skew? So that neither theta nor gamma/delta plays a role and you can capitalize just on the behavior of the skew (e.g. SPY, SPY skew).
Thanks
Buy lower strikes and sell higher strikes at a ratio that makes you gamma neutral, then even up your deltas by buying/selling the underlying. Now you're long the skew and gamma and delta neutral. The ratio doesn't have to be 1 by 2 or 1 by 3 or anything even. Let the relative gammas of the two strikes dictate the ratio.
Keep in mind that you won't stay gamma neutral as the underlying moves. When the underlying goes up, you will get short gamma. When the underlying goes down, you will get long gamma.
That's advantageous btw because when the underlying goes up and you get short gamma you will also get short vega as, conveniently, implied volatility undoubtedly falls. As the underlying goes down you will get long vega which is nice because volatility will rise.
You can take advantage of that phenomenon to "scalp out" of your position like this: when SPY goes up you will get short vega and volatility will drop. You can buy in your now-cheaper higher strike, realizing a profit and evening up your gammas and vegas. When SPY goes down you will get long vegas and volatility will rise. You can now sell some of your now-more-expensive lower strike, again evening up your gammas and vegas and realizing a profit.
The downside of this whole approach is that since you paid a higher volatility for the lower strike, there is more theta in your long strike than in your short strike. So time works against you.
One more thing to keep in mind - the closer you get to expiration, the more "unstable" the gamma neutrality of your position becomes. That is to say, the closer to expiration, the more your overall position gamma changes as the underlying moves. With a lot of time remaining, the gammas are very stable - your overall position gamma changes very little as the underlying moves. Within a week or two of expiration, the position gamma changes drastically with each move of the underlying and it becomes difficult or impossible to manage the position gamma neutral. And once the gamma neutrality is lost, the delta neutrality is lost as well