SLIDE 26 Algorithmic Fairness
Compass ProPublica Predictive Parity (True
Positive & Negative)
Same Score = Same % Re‐
arrest
E.g., High risk = 20% re‐arrest
(violence)
Industry standard
False Positive & Positive
Parity
AA’s not re‐arrested 2X more
likely mis‐labeled high risk
Whites rearrested 2X more
likely mislabled “low” risk
The Base Rate Problem
The ProPublica disparities are unavoidable
Confirmed by Center for Court Innovation
Why?
AA’s more likely to be arrested Tools more likely to predict AA’s arrests Higher proportion of mistaken predictions
No tool can satisfy ProPublica and Compass
51 52
Defender Initiative 10th Annual Conference Session 3 - MJC Bail REform Pannel BB slides February 28, 2020