1. ROC Curve Demo

2. |<-logits of the 1s->| |
Say 1
Say
%1s 1
| |
%0s
|<-logits of the 1s->| |
|<-logits of the 0s->|

3. Say 1
Say

4. Say 1
Say

5. Say 1
Say

6. Say 1
Say

7. Say 1
Say

8. Say 1
Say

9. Say 1
Say

10. Example 2
Say 1 2 18 8 12 15 5
Say 0
X=10
X=13
X=16
1 - specificity

11. 2 18 8 12 15 5 Example 2 0 1 X=10 Say 1 X=13 Say 0 X=16 (2/25, 18/35) 2 18 8 12 15 5
X=10
X=13
X=16
Say 1
Say 0
(2/25, 18/35)
1 - specificity

12. Example 2 2 18 8 12 15 5
X=10
X=13
X=16
(10/25, 30/35)
(2/25, 18/35)
Say 1
Say 0
1 - specificity

13. Example 2 2 18 8 12 15 5
X=10
X=13
X=16
(10/25, 30/35)
(1, 1)
(2/25, 18/35)
Say 1
Say 0
1 - specificity

14. 2 18 8 12 15 5 Example 2 0 1 X=10 Tie Tie Say 1 X=13 Say 0 X=16 2 18 8 12 15 5
X=10
X=13
X=16
Tie Tie
Say 1
Say 0
18 x 23
1 - specificity

15. 2 18 8 12 15 5 Example 2 0 1 X=10 X=13 X=16 Tie Tie 15 x 12 Tie 2 18 8 12 15 5
X=10
X=13
X=16
Tie Tie
15 x 12
Tie
Tie Tie
Say 1
Say 0
18 x 23
Tie
1 - specificity

16. 2 18 8 12 15 5 Example 2 0 1 X=10 X=13 X=16 15x5/2 Tie Tie 8x12/2 Tie 2 18 8 12 15 5
X=10
X=13
X=16
15x5/2
Tie Tie
8x12/2
Tie
15 x 12
Tie
Tie Tie
2x18/2
18 x 23
Tie Tie
Say 1
Tie
Say 0
1 - specificity
AUC Area Under Curve = concordant pair plus ½ ties (proportions)
Pairs: 25x35=875 with 0 paired with 1.
Proportion Concordant: (18x23+12x15)/(25x35)=(18/25)x(23/35)+(12/25)x(15/35)
½ Proportion Ties ½(2x18 + 8x x5)/(25x35)
AUC = 697.5/875 =