Why is the Confusion matrix generated by Performance Vector and the Predictive model is different?

glybentta
glybentta New Altair Community Member
edited November 2024 in Community Q&A

I am using Gradient Boosted Trees for my dataset. The process output shows the Performance Vector which gives the accuracy and confusion matrix, and Gradient Boosted Model which gives the model metrics, Confusion matrix, Variable importance, model summary and scoring history. But both the confusion matrix are different. Which should confusion matrix should I consider to evaluate my model?

Best Answer

  • MartinLiebig
    MartinLiebig
    Altair Employee
    Answer ✓

    Hi,

     

    the confusion matrix in the model are _training_ errors. So you should usually work on the Performance Vector, not the Gradient Boosted Model values. These are sometimes interesting to have a  look on overfitting (e.g. add more complexity or not).

     

    ~Martin

Answers

  • MartinLiebig
    MartinLiebig
    Altair Employee
    Answer ✓

    Hi,

     

    the confusion matrix in the model are _training_ errors. So you should usually work on the Performance Vector, not the Gradient Boosted Model values. These are sometimes interesting to have a  look on overfitting (e.g. add more complexity or not).

     

    ~Martin

  • IngoRM
    IngoRM New Altair Community Member

    > These are sometimes interesting to have a  look on overfitting (e.g. add more complexity or not).

     

    True, but in general I am in the school of "just forget training errors completely".  They create more damage than anything else :smileywink:

     

    Have a nice weekend,

    Ingo