Fairness via thresholds
Sepsis label = fill color · Predicted positive (≥ threshold) = white outline
Reset
Group A
TPR · FPR · PPP
threshold
0.50
t = 0.50
0
1
true sepsis
true non-sepsis
pred +
TP
0
TPR 0.000
FP
0
FPR 0.000
FN
0
PPP 0.000
TN
0
N 0
Group B
TPR · FPR · PPP
threshold
0.50
t = 0.50
0
1
true sepsis
true non-sepsis
pred +
TP
0
TPR 0.000
FP
0
FPR 0.000
FN
0
PPP 0.000
TN
0
N 0
Metrics
Δ
Equalized Odds
|ΔTPR| + |ΔFPR| = 0.000
ΔTPR = TPR
A
− TPR
B
· ΔFPR = FPR
A
− FPR
B
Equal Opportunity
|ΔTPR| = 0.000
ΔTPR = TPR
A
− TPR
B
Statistical Parity
|ΔPPP| = 0.000
ΔPPP = PPP
A
− PPP
B
Disparate Impact
DI = 1.000
log(DI) = log(PPP
A
) − log(PPP
B
)
DI = exp(log(DI)) = PPP
A
/ PPP
B
TPR
= TP / (TP + FN)
FPR
= FP / (FP + TN)
PPP
= (TP + FP) / N