Confusion Matrix Results Sensitivity

How do I calculate the sensitivity and specificity with the confusionmat command? What is the position of TP, FP, FN, TN in the confusion matrix provided by matlab? I use the "confusionmat".

Answer 1

[YT]

Just use the following.

[cm, order] = confusionmat(real_values,predicted_values)

You can check it here ( https://www.mathworks.com/help/stats/confusionmat.html ).

Assuming your confusionmatrix is 2x2, it will look like this:

    %CONFUSIONMAT OUTPUT
    %%%%%%%%%%%%%%%%%%%%%%
    %          predicted
    %         | 0     1
    %    r  -----------
    %    e  0 | TN   FP
    %    a  1 | FN   TP
    %    l
    %%%%%%%%%%%%%%%%%%%%%%

*EDIT

confusionmat() does not calculate sensitivity, accuracy, F-score and those kind of derivations for you, you need to do them yourself. Just check this out, it's pretty easy.

[Gledson Melotti]

Thanks a lot for the help.

[Gledson Melotti]

Matlab does not calculate the measures (Fscore, TNR, TPR). So why does it provide the following command: accuracy = mean (diag (confMat))?