Extract most important features (per Class) using mutual_info_classif












0














I'm using mutual_info_classif to determine the most important words for a binary text-classification task as:



mi_score = mutual_info_classif(X, y)


but the above gives an array of feature scores without reference to the corresponding classes



Is there a way to get the most important features per class using MI?



P.s., I've already tried Chi2 but it gives the same feature rank for both classes










share|improve this question



























    0














    I'm using mutual_info_classif to determine the most important words for a binary text-classification task as:



    mi_score = mutual_info_classif(X, y)


    but the above gives an array of feature scores without reference to the corresponding classes



    Is there a way to get the most important features per class using MI?



    P.s., I've already tried Chi2 but it gives the same feature rank for both classes










    share|improve this question

























      0












      0








      0







      I'm using mutual_info_classif to determine the most important words for a binary text-classification task as:



      mi_score = mutual_info_classif(X, y)


      but the above gives an array of feature scores without reference to the corresponding classes



      Is there a way to get the most important features per class using MI?



      P.s., I've already tried Chi2 but it gives the same feature rank for both classes










      share|improve this question













      I'm using mutual_info_classif to determine the most important words for a binary text-classification task as:



      mi_score = mutual_info_classif(X, y)


      but the above gives an array of feature scores without reference to the corresponding classes



      Is there a way to get the most important features per class using MI?



      P.s., I've already tried Chi2 but it gives the same feature rank for both classes







      scikit-learn text-classification






      share|improve this question













      share|improve this question











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      asked Nov 12 at 17:51









      Stan

      4952723




      4952723
























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          Mutual information is a measure of dependence between 2 variables. In your case, between each of the attribute variables and the "Class" variable. The mutual information will give a higher score, when the attribute variable creates a better split of the target variable. This means you only get one score that describes the strength between the attirubte and the class. The most important feature is the one that best distinguishes between all of the classes.



          If you have a class with multiple labels (not a binary class), you can create a new class variable for each label by using dummy variables.
          For example, assume your class name is CLASS, and it holds 3 different labels: "Red", "Green" and "Blue". Create 3 new target variables, the first will be called "Is_Red", and it will hold "Yes" if CLASS=="Red" or "No" Otherwise. In this manner you can see which attribute best distinguish between each specific instance of the class. You will have to run the mutual information per new class variable.






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            Mutual information is a measure of dependence between 2 variables. In your case, between each of the attribute variables and the "Class" variable. The mutual information will give a higher score, when the attribute variable creates a better split of the target variable. This means you only get one score that describes the strength between the attirubte and the class. The most important feature is the one that best distinguishes between all of the classes.



            If you have a class with multiple labels (not a binary class), you can create a new class variable for each label by using dummy variables.
            For example, assume your class name is CLASS, and it holds 3 different labels: "Red", "Green" and "Blue". Create 3 new target variables, the first will be called "Is_Red", and it will hold "Yes" if CLASS=="Red" or "No" Otherwise. In this manner you can see which attribute best distinguish between each specific instance of the class. You will have to run the mutual information per new class variable.






            share|improve this answer


























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              Mutual information is a measure of dependence between 2 variables. In your case, between each of the attribute variables and the "Class" variable. The mutual information will give a higher score, when the attribute variable creates a better split of the target variable. This means you only get one score that describes the strength between the attirubte and the class. The most important feature is the one that best distinguishes between all of the classes.



              If you have a class with multiple labels (not a binary class), you can create a new class variable for each label by using dummy variables.
              For example, assume your class name is CLASS, and it holds 3 different labels: "Red", "Green" and "Blue". Create 3 new target variables, the first will be called "Is_Red", and it will hold "Yes" if CLASS=="Red" or "No" Otherwise. In this manner you can see which attribute best distinguish between each specific instance of the class. You will have to run the mutual information per new class variable.






              share|improve this answer
























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                0






                Mutual information is a measure of dependence between 2 variables. In your case, between each of the attribute variables and the "Class" variable. The mutual information will give a higher score, when the attribute variable creates a better split of the target variable. This means you only get one score that describes the strength between the attirubte and the class. The most important feature is the one that best distinguishes between all of the classes.



                If you have a class with multiple labels (not a binary class), you can create a new class variable for each label by using dummy variables.
                For example, assume your class name is CLASS, and it holds 3 different labels: "Red", "Green" and "Blue". Create 3 new target variables, the first will be called "Is_Red", and it will hold "Yes" if CLASS=="Red" or "No" Otherwise. In this manner you can see which attribute best distinguish between each specific instance of the class. You will have to run the mutual information per new class variable.






                share|improve this answer












                Mutual information is a measure of dependence between 2 variables. In your case, between each of the attribute variables and the "Class" variable. The mutual information will give a higher score, when the attribute variable creates a better split of the target variable. This means you only get one score that describes the strength between the attirubte and the class. The most important feature is the one that best distinguishes between all of the classes.



                If you have a class with multiple labels (not a binary class), you can create a new class variable for each label by using dummy variables.
                For example, assume your class name is CLASS, and it holds 3 different labels: "Red", "Green" and "Blue". Create 3 new target variables, the first will be called "Is_Red", and it will hold "Yes" if CLASS=="Red" or "No" Otherwise. In this manner you can see which attribute best distinguish between each specific instance of the class. You will have to run the mutual information per new class variable.







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Nov 13 at 13:38









                Roee Anuar

                574514




                574514






























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