Race was never an input, yet the inputs partly give it away: 0.68, where a guess scores 0.50
Race was never an input, yet the inputs partly give it away: 0.68, where a guess scores 0.50
Linear probe telling Black from White applicants, AUC, mean over 5 seeds
0.50pure guess (shuffled labels)
0.68Read from the allowed inputs
1.00 = never wrong
How to read this: 0.50 means the probe is guessing, 1.00 means it is never wrong. The further right the orange dot, the more the allowed fields give race away.
Note: The strongest single proxies are property value (0.599), income (0.595) and debt-to-income band (0.594). Inside the network the probe scores 0.673 and 0.659 on hidden layers 1 and 2 (random-weights control 0.642), so training does not make race easier to read. This measures information a probe can extract, not discrimination or intent. 500,000-row national sample; the network's own denial AUC is 0.838.
Source: public HMDA filings, 2023 to 2025. hmda-audit analysis.