Thanks that helped.

But i just can't get an higher accuracy then 45%... don't now why. also
with logicstic regression and so on..

Is there a way to combine for example an SVM with a decision tree?

Herb

On 2 June 2015 at 11:19, Michael Eickenberg <michael.eickenb...@gmail.com>
wrote:

> Some configurations are not implemented or difficult to evaluate in the
> dual. Setting dual=True/False doesn't change the result, so please don't
> vary it as you would vary other parameters. It can however sometimes yield
> a speed-up. Here you should try setting dual=False as a first means of
> debugging.
>
> Michael
>
> On Tue, Jun 2, 2015 at 11:04 AM, Herbert Schulz <hrbrt....@gmail.com>
> wrote:
>
>> Does anyone know why this failure occurs?
>>
>> ValueError: Unsupported set of arguments: loss='l1' and
>> penalty='squared_hinge'are not supported when dual=True, Parameters:
>> penalty='l1', loss='squared_hinge', dual=True
>>
>> I'm using a Linear SVC ( in andreas example code).
>>
>>
>> On 1 June 2015 at 13:38, Herbert Schulz <hrbrt....@gmail.com> wrote:
>>
>>> Cool, thx for that!
>>>
>>>
>>> Herb
>>>
>>> On 1 June 2015 at 12:16, JAGANADH G <jagana...@gmail.com> wrote:
>>>
>>>> Hi
>>>>
>>>> I have listed sklearn feature selection with minimal examples here
>>>>
>>>>
>>>> http://nbviewer.ipython.org/github/jaganadhg/data_science_notebooks/blob/master/sklearn/scikit_learn_feature_selection.ipynb
>>>>
>>>> Jagan
>>>>
>>>> On Thu, May 28, 2015 at 10:14 PM, Herbert Schulz <hrbrt....@gmail.com>
>>>> wrote:
>>>>
>>>>> Thank's to both of you!!! I realy appreciate it! I will try everything
>>>>> this weekend.
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Herb
>>>>>
>>>>> On 28 May 2015 at 18:21, Sebastian Raschka <se.rasc...@gmail.com>
>>>>> wrote:
>>>>>
>>>>>> I agree with Andreas,
>>>>>> typically, a large number of features also shouldn't be a big problem
>>>>>> for random forests in my experience; however, it of course depends on the
>>>>>> number of trees and training samples.
>>>>>>
>>>>>> If you suspect that overfitting might be a problem using
>>>>>> unregularized classifiers, also consider "dimensionality
>>>>>> reduction"/"feature exctraction" techniques to compress the feature 
>>>>>> space,
>>>>>> e.g., linear or kernel PCA, or other methods listed in the manifold
>>>>>> learning section on the scikit-website.
>>>>>>
>>>>>> However, there are scenarios where you'd want to keep the "original"
>>>>>> features (in contrast to e.g., principal components), and there are
>>>>>> scenarios where linear methods such as LinearSVC(penalty='l1') may not 
>>>>>> work
>>>>>> so well (e.g., for non-linear problems). The optimal solution would be to
>>>>>> exhaustively test all feature combinations to see which works best,
>>>>>> however, this can be quite costly. For demonstration purposes, I
>>>>>> implemented "sequential backward selection" (
>>>>>> http://rasbt.github.io/mlxtend/docs/sklearn/sequential_backward_selection/)
>>>>>> some time ago; a simple greedy alternative to the exhaustive search, 
>>>>>> maybe
>>>>>> you are lucky and it works well in your case? . When I find time after my
>>>>>> summer projects, I am planning to implement some genetic algos for 
>>>>>> feature
>>>>>> selection...
>>>>>>
>>>>>> Best,
>>>>>> Sebastian
>>>>>>
>>>>>>
>>>>>> On May 28, 2015, at 11:59 AM, Andreas Mueller <t3k...@gmail.com>
>>>>>> wrote:
>>>>>>
>>>>>>  Hi Herbert.
>>>>>> 1) Often reducing the features space does not help with accuracy, and
>>>>>> using a regularized classifier leads to better results.
>>>>>> 2) To do feature selection, you need two methods: one to reduce the
>>>>>> set of features, another that does the actual supervised task
>>>>>> (classification here).
>>>>>>
>>>>>> Have you tried just using the standard classifiers? Clearly you tried
>>>>>> the RF, but I'd also try a linear method like 
>>>>>> LinearSVC/LogisticRegression
>>>>>> or a kernel SVC.
>>>>>>
>>>>>> If you want to do feature selection, what you need to do is something
>>>>>> like this:
>>>>>>
>>>>>> feature_selector = LinearSVC(penalty='l1')  #or maybe start with
>>>>>> SelectKBest()
>>>>>> feature_selector.train(X_train, y_train)
>>>>>>
>>>>>> X_train_reduced = feature_selector.transform(X_train)
>>>>>> X_test_reduced = feature_selector.transform(X_test)
>>>>>>
>>>>>> classifier = RandomForestClassifier().fit(X_train_reduced, y_train)
>>>>>>
>>>>>> prediction = classifier.predict(X_test_reduced)
>>>>>>
>>>>>>
>>>>>> Or you use a pipeline, as here:
>>>>>> http://scikit-learn.org/dev/auto_examples/feature_selection/feature_selection_pipeline.html
>>>>>> Maybe we should add a version without the pipeline to the examples?
>>>>>>
>>>>>> Cheers,
>>>>>> Andy
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 05/28/2015 08:32 AM, Herbert Schulz wrote:
>>>>>>
>>>>>> Hello,
>>>>>> I'm using scikit-learn for machine learning.
>>>>>> I have 800 samples with 2048 features, therefore i want to reduce my
>>>>>> features to get hopefully a better accuracy.
>>>>>>
>>>>>> It is a multiclass problem (class 0-5), and the features consists of
>>>>>> 1's and 0's:  [1,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0,0....,0]
>>>>>>
>>>>>> I'm using the Randfom Forest Classifier.
>>>>>>
>>>>>> Should i just feature select the training data ? And is it enough if
>>>>>> I'm using this code:
>>>>>>
>>>>>>     X_train, X_test, y_train, y_test = train_test_split(X, y,
>>>>>> test_size=.3)
>>>>>>
>>>>>>
>>>>>> clf=RandomForestClassifier(n_estimators=200,warm_start=True,criterion='gini',
>>>>>> max_depth=13)
>>>>>>     clf.fit(X_train, y_train).transform(X_train)
>>>>>>
>>>>>>     predicted=clf.predict(X_test)
>>>>>>     expected=y_test
>>>>>>     confusionMatrix=metrics.confusion_matrix(expected,predicted)
>>>>>>
>>>>>> Cause the accuracy didn't get higher. Is everything ok in the code or
>>>>>> am I doing something wrong?
>>>>>>
>>>>>> I'll be very grateful for your help.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> ------------------------------------------------------------------------------
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Scikit-learn-general mailing 
>>>>>> listScikit-learn-general@lists.sourceforge.nethttps://lists.sourceforge.net/lists/listinfo/scikit-learn-general
>>>>>>
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>>>>>
>>>>>
>>>>> ------------------------------------------------------------------------------
>>>>>
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>>>>
>>>>
>>>> --
>>>> **********************************
>>>> JAGANADH G
>>>> http://jaganadhg.in
>>>> *ILUGCBE*
>>>> http://ilugcbe.org.in
>>>>
>>>>
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