Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-10-19 Thread Lars Buitinck
2013/10/19 Andreas Mueller : > The multi-class documentation says > "You don’t need to use these estimators unless you want to experiment > with different multiclass strategies: > all classifiers in scikit-learn support multiclass classification > out-of-the-box. Below is a summary of the classifie

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-10-18 Thread Andreas Mueller
On 09/25/2013 05:31 AM, Lars Buitinck wrote: > 2013/9/25 Luca Cerone : >> I am sorry, but I went into the user documentation for logistic regression >> and multiclass classification and didn't find any information about it > Hm, maybe we should put this in a more prominent place like the > tutorial

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Luca Cerone
On 25 September 2013 13:55, Olivier Grisel wrote: > 2013/9/25 Luca Cerone : > >> > (this is not explained in the user guide > >> > > >> > > http://scikit-learn.org/stable/modules/linear_model.html#logistic-regression > , > >> > though). > >> > >> All our classifiers support multiclass classificat

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Olivier Grisel
2013/9/25 Luca Cerone : >> > (this is not explained in the user guide >> > >> > http://scikit-learn.org/stable/modules/linear_model.html#logistic-regression, >> > though). >> >> All our classifiers support multiclass classification and this is >> documented in various places. > > > I am sorry, but

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Vlad Niculae
>> There are still a few things that are not clear to me from the >> documentation. Can you customize the classifier to perform a different >> decision function? > > You can subclass it and override the decision_function method. While true, this can be misleading. You're just changing the final st

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Lars Buitinck
2013/9/25 Luca Cerone : > I am sorry, but I went into the user documentation for logistic regression > and multiclass classification and didn't find any information about it Hm, maybe we should put this in a more prominent place like the tutorial. I'll check the docs if I have time. > for the pen

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Luca Cerone
> > > (this is not explained in the user guide > > > http://scikit-learn.org/stable/modules/linear_model.html#logistic-regression > , > > though). > > All our classifiers support multiclass classification and this is > documented in various places. > I am sorry, but I went into the user documentat

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Lars Buitinck
2013/9/25 Luca Cerone : > This morning I checked the source for LogisticRegression in > sklearn/linear_model/logistic.py and realized that by default it performs > multiclass classification > (this is not explained in the user guide > http://scikit-learn.org/stable/modules/linear_model.html#logisti

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Luca Cerone
Dear Olivier, thanks for your reply. On 25 September 2013 10:39, Olivier Grisel wrote: > LogisticRegression is a already multiclass classifier by default using > the One vs Rest / All strategy by default (as implemented internally > by liblinear which LogisticRegression is a wrapper of). So you

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-25 Thread Olivier Grisel
LogisticRegression is a already multiclass classifier by default using the One vs Rest / All strategy by default (as implemented internally by liblinear which LogisticRegression is a wrapper of). So you don't need to use OneVsRest in this case. If you want more info on multiclass reductions here i

Re: [Scikit-learn-general] Multiclass Logistic Regression.

2013-09-24 Thread Luca Cerone
Ok training a OneVsAll classifier it was actually easy. To inspect the individual classifier I can use the .estimators_ attribute? Do the estimators in it correspond to the .classes_ that is the estimators_[0] is trained to recognize .classes_[0] vs the other and so on? Is there a way to check how

[Scikit-learn-general] Multiclass Logistic Regression.

2013-09-24 Thread Luca Cerone
Dear all, I am practising with scikit-learn to solve multiclass classification problems. As an exercise I am trying to build a model to predict the digits dataset available with scikit-learn. Ideally I would like to solve this using logistic regression, building a predictor for each digit (one v