2013/10/15 Olivier Grisel <olivier.gri...@ensta.org>:
> 2013/10/15 Alexandre Gramfort <alexandre.gramf...@telecom-paristech.fr>:
>>> I did find the part in coordinate_descent.py where alpha_max is chosen, but
>>> I don't fully understand the reasoning behind it:
>>>
>>> alpha_max = np.abs(Xy).max() / (n_samples * l1_ratio)
>>
>> it can be derived from the KKT optimality conditions of the Lasso problem.
>
> Would be great to add a link to an online reference or the derivation
> somewhere in the doc.

Also is it impacted by the lack of greedy data-centering in the sparse
case? It seems it does to me.


-- 
Olivier
http://twitter.com/ogrisel - http://github.com/ogrisel

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