This test is purely non-parametric, it is based on the characteristic
function evaluated at the data (OK basically their Fourier transform),
following a characterization of independence by A. Renyi, though its actual
implementation depends on pairwise distances and that is something I must
understand better first.

I made a proof of concept creating a X~N(0,1) and Y=X^2. An ideal
non-linear correlation should yield 1, since this is a purely functional
relationship. It is well-known that Pearson's correlation is 0 for this
case. Rizzo and coauthors' coefficient yields 0.49 in my test.

Also, according to their paper "Brownian Distance Covariance", their
p-value is always less than that of the correlation (see the examples
there).



2012/9/3 Gael Varoquaux <[email protected]>

> On Mon, Sep 03, 2012 at 01:54:58AM +0200, Analytic Bastard wrote:
> >    It would be useful to test whether any classification or regression
> >    problem can be tractable. After all, if two variables are
> independent, it
> >    won't be possible to try to classify or do regression with them.
>
> In my experience, such tests are not very powerfull, as they are weakly
> parametric, and thus do not give a good answer to that question.
>
> Do you have an example of the use of these tools on real world problem?
>
> Gael
>
>
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and
> threat landscape has changed and how IT managers can respond. Discussions
> will include endpoint security, mobile security and the latest in malware
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Scikit-learn-general mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/scikit-learn-general
>
------------------------------------------------------------------------------
Live Security Virtual Conference
Exclusive live event will cover all the ways today's security and 
threat landscape has changed and how IT managers can respond. Discussions 
will include endpoint security, mobile security and the latest in malware 
threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
_______________________________________________
Scikit-learn-general mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/scikit-learn-general

Reply via email to