logistic regression - number of coefficients

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logistic regression - number of coefficients

Sridevi Parise

I am using the logistic regression in Weka on a training dataset
containing 42 attributes where one of the columns is the class label. When
I get the model, the number of coeficients displayed is 40 plus an
intercept rather than 41 plus an intercept. What could be the reason for
the missing coefficient?

Also when I train by removing, say, around 10 attributes, it gives the
correct number of coefficients.

Thanks for any help,

Sridevi


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Re: logistic regression - number of coefficients

Thomas G. Dietterich
Logistic regression removes all features that provide no information
about the class (e.g., all features that have constant values).  It
would be nice if it would display the names of the features next to
the coefficients (and/or display all features but just assign 0
coefficients to the useless features).

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Thomas G. Dietterich, Professor   Voice: 541-737-5559
School of Electrical Engineering  FAX:   541-737-3014
  and Computer Science            URL:   http://www.cs.orst.edu/~tgd
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>>>>> "SP" == Sridevi Parise <[hidden email]> writes:

    SP> I am using the logistic regression in Weka on a training dataset
    SP> containing 42 attributes where one of the columns is the class label. When
    SP> I get the model, the number of coeficients displayed is 40 plus an
    SP> intercept rather than 41 plus an intercept. What could be the reason for
    SP> the missing coefficient?

    SP> Also when I train by removing, say, around 10 attributes, it gives the
    SP> correct number of coefficients.

    SP> Thanks for any help,

    SP> Sridevi


    SP> _______________________________________________
    SP> Wekalist mailing list
    SP> [hidden email]
    SP> https://list.scms.waikato.ac.nz/mailman/listinfo/wekalist


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