Step 2: Design fair pricing

A practical framework for fair algorithmic pricing

Author

Fei Huang, UNSW Sydney

How to achieve fairness?

Implement anti-discrimination strategies at pre-processing, in-processing, or post-processing, linked to the fairness criteria from Step 1 (Xin and Huang 2024).

Model–criterion mapping

Model Criterion Approach
M0 (full) baseline Uses X_P and X_{NP}
MU (unawareness) FTU \hat{Y} = f(X_{NP}) only
MDP (debiased) DP Pre-process X_{NP} to remove dependence on X_P
MCDP CDP Legitimate X_{NP_{\text{legit}}} retained; others debiased
MC (control) CPV Fit M0; average over X_P at prediction

Pre-processing (MDP, MCDP)

  • Disparate impact remover: align group distributions of X_{NP}
  • Orthogonal predictors: residualise X_{NP} on X_P

MCDP allows group differences only through legitimate variables (e.g. claims history, vehicle type).

Post-processing (MC)

\hat{Y}_{MC} = \frac{1}{N}\sum_{j=1}^N \hat{f}_{M0}(X_{NP}, X_P = x_{p_j})

Protected attributes used in training only; averaged out at prediction, giving better proxy control than MU alone.

Implementation

  • Empirical comparison uses GLM and XGBoost on French auto data (Xin and Huang 2024)
  • Retain baseline M0 for welfare and audit comparisons (Steps 3–4)
  • Document pre- / in- / post-processing choice and reproducible pipeline

Checklist

References

Xin and Huang (2024)

References

Xin, Xi, and Fei Huang. 2024. “Antidiscrimination Insurance Pricing: Regulations, Fairness Criteria, and Models.” North American Actuarial Journal 28 (2): 285–319.