From: Flea index predicts plague epizootics among great gerbils (Rhombomys opimus) in the Junggar Basin China plague focus
Prediction criterion
Plague epizootic
Total
Yes
No
A
Flea index ≥ 12.63 (positive)
9
37
46
Flea index < 12.63 (negative)
4
48
52
13
85
98
B
Flea index ≥ 10.59 (positive)
47
14
61
Flea index < 10.59 (negative)
12
25
59
39