[R] Test for Random Points on a Sphere

[R. Michael Weylandt]

On Fri, Oct 5, 2012 at 5:39 PM, Lorenzo Isella <lorenzo.isella at gmail.com> wrote:
> Dear All,
> I implemented an algorithm for (uniform) random rotations.
> In order to test it, I can apply it to a unit vector (0,0,1) in Cartesian
> coordinates.
> The result is supposed to be a set of random, uniformly distributed, points
> on a sphere (not the point of the algorithm, but a way to test it).
> This is what the points look like when I plot them, but other then
> eyeballing them, can anyone suggest a test to ensure that I am really
> generating uniform random points on a sphere?
> Many thanks
>

Gut says to divide the surface into n bits of equal area and see if
the points appear uniformly in those using something chi-squared-ish,
but I'm not aware of a canonical way to do so.

Cheers,
Michael

> Lorenzo
>
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