I use the function auc
in the R
package pROC
to calculate the auc
value in a simulation study. test.y
is the observed response, y_pred_mle
is the predicted response.
> test.y
test.y
1 -1
2 -1
3 -1
4 -1
5 -1
6 -1
7 1
8 1
9 1
10 1
11 1
12 1
> y_pred_mle
[,1]
76 -166.7094
53 -203.4014
52 -220.0880
51 -189.4703
95 -222.5294
72 -207.0304
24 722.8809
44 727.5353
12 770.5053
42 783.7437
27 733.3144
3 773.2688
> out_auc_mle<- auc( test.y, y_pred_mle )
> out_auc_mle
[1] Inf
I wonder how can this generate Inf
value? In my understanding on auc
, the range of auc
should be 0
to 1
. I am not asking an coding question. I just wonder how the auc value can be Inf
. Can anybody explain me about is it possible that the auc
is Inf
? Then how to interpret it?