I need to identify the diffetent outputs of confusionmat

Hello!

I`m using the funtion confusionmat and I need to know the position of true positives and true negatives in this matrix.

For example

ans=

156 30

40 79

In this case, which are the true positives and true negatives if this is the output of confusionmat?

[muhammad]

hello i am also facing the same situation ..Did you get the solution?

Answer 1

[Tom Lane]

The matrix is the count of actual and predicted values for each class. You can use the second output to get the class names. For example:

load fisheriris
tree = fitctree(meas,species);
[c,a] = confusionmat(species,predict(tree,meas))
c =
    50     0     0
     0    47     3
     0     0    50
a = 
    'setosa'
    'versicolor'
    'virginica'

You could compute true negatives and positives from this information, but they are not returned directly.

[muhammad]

my C is like this as shown in below

0 670

181 10909

and a(order) is

1

2

please let me know how to find the TP,TN,Fp,Fn.