FP rate difference diminished, but FN rate difference greatly increased?

[MatthijsdeJ]

When testing the equalized odds algorithm on my data, I checked the metrics. I found that it only diminishes the difference between FP rates, but it actually greatly increased the difference for FN rates. This does not seem allign with Equalized Odds, AFAIK.

Original group 0 model:
Group size: 943.000
Prediction Accuracy: 0.690
FP rate: 0.113
FN rate: 0.196

Original group 1 model:
Group size: 641.000
Prediction Accuracy: 0.771
FP rate: 0.062
FN rate: 0.167

Equalized odds group 0 model:
Group size: 943.000
Prediction Accuracy: 0.652
FP rate: 0.063
FN rate: 0.285

Equalized odds group 1 model:
Group size: 641.000
Prediction Accuracy: 0.761
FP rate: 0.076
FN rate: 0.162

[MatthijsdeJ]

It is worse for the calibrated equalized odds model. Here, both the difference between FP rates and FN rates increase, even when using the 'weighted' option.

Original group 0 model:
Group size: 2331.000
Prediction Accuracy: 0.701
FP rate: 0.095
FN rate: 0.203

Original group 1 model:
Group size: 1628.000
Prediction Accuracy: 0.740
FP rate: 0.052
FN rate: 0.208

Equalized odds group 0 model:
Group size: 2331.000
Prediction Accuracy: 0.701
FP rate: 0.095
FN rate: 0.203

Equalized odds group 1 model:
Group size: 1628.000
Prediction Accuracy: 0.741
FP rate: 0.035
FN rate: 0.224