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A comment on Gaussian Distributions Are Soap Bubbles. Parent comment

Re:Gaussian Distributions Are Soap Bubbles by conjectures on Saturday November 11, 2017 @01:01PM (#15677313)
On that point my teeth were grinding because it assumes an identity covariance matrix. Ie the bubble needn't even be spherical.

The second is that the squared norm has a chisq distribution. There's no point simulating it. You can just plot the pdf, and have all kinds of facts about its mean, var, entropy etc. Also, iirc Shannon had something to say about this.

However, I do think these facts are worth a reminder.

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Re:Gaussian Distributions Are Soap Bubbles by jjoonathan on Saturday November 11, 2017 @01:27PM (#15677430)
I don't (on the first point). Everyone with the background to understand the problem under discussion and appreciate the explanation already understands that Gaussians are parametrized. I challenge you to find a counterexample. The specifics of non-isotropic parametrizations are even less relevant to the discussion than scalar parametrization.

On the second point, I agree that the approximation deserves a mention.

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