How can I find the confusion matrix for a three class problem and thenfind specificity, sensitivity and accuracy from them.

How can I find the confusion matrix for a three class problem and then find specificity, sensitivity and accuracy from them.

Answer 1

[Ilya]

If you have Statistics Toolbox, take a look at the confusionmat function. The accuracy is simply the sum of the diagonal elements divided by the sum of all elements in the matrix. Specificity and sensitivity are unambiguously defined for binary classification. You'd have to come up with your definitions for 3 classes.