Evidence · The claim ledger
Fairness & disparate impact2
Every cited claim this site makes in this evidence area, with the sources that ground it. Source keys link back to the full reference lists on the Evidence Registry.
EmpiricalWhere base rates differ between groups, a risk instrument cannot be both well calibrated across those groups and equal i…
Where base rates differ between groups, a risk instrument cannot be both well calibrated across those groups and equal in its error rates across them. The volume's criminal-justice chapter restates this result, which the site already carries in its primary form from Chouldechova's 2017 analysis of recidivism instruments. It is a property of the scoring instrument and the population it is applied to, not a defect that a better model removes.
Sources: ahn2026, chouldechova2017
Appears on: /domains/security-operations-fraud
EmpiricalThe volume's criminal-justice chapter reports a statewide pretrial reform, evaluated by Anderson and colleagues in 2019,…
The volume's criminal-justice chapter reports a statewide pretrial reform, evaluated by Anderson and colleagues in 2019, in which the pretrial jail population fell without a rise in crime or in failure to appear. Over the same period the racial composition of those still detained did not materially change. Both halves are the finding: the level moved and the composition did not.
Sources: ahn2026
Appears on: /domains/security-operations-fraud