SVI, SABR, or parabola on AAPL?
In a previous post, I took a look at least squares spline and parabola fits on AAPL 1m options market volatilities. I would have imagined SVI to fit even better since it has 5 parameters, and SABR to do reasonably well.
It turns out that the simple parabola has the lowest RMSE, and SVI is not really better than SABR on that example.
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SVI, SABR, least squares parabola fitted to AAPL 1m options
Note that this is just one single example, unlikely to be representative of anything, but I thought this was interesting that in practice, a simple parabola can compare favorably to more complex models.