All 5 prompts have been successfully implemented. The project is now positioned as an applied ML system with evaluation and fairness capabilities.
- Updated README.md header to "Policy Recommender — Fairness-Aware ML Decision System"
- Added "Why ML is Used" section explaining:
- Eligibility is policy-driven (rule-based, non-negotiable)
- Ranking is data-driven (ML captures patterns for relevance ordering)
- Trade-off: Interpretability > raw accuracy for government systems
- Updated features list to highlight ML ranking, fairness analysis, and evaluation metrics
- Updated tech stack to explicitly mention ML libraries (scikit-learn, NDCG, Precision@k, MAP)
Impact: Project now reads as ML-driven, not backend-first
- Created
src/evaluation/ranking_metrics.pywith:ndcg_at_k(): Normalized Discounted Cumulative Gainprecision_at_k(): Top-k precision with relevance thresholdmean_average_precision(): MAP across multiple rankingsevaluate_ranking()andevaluate_ranking_batch(): Comprehensive evaluation functions- Helper functions:
dcg_at_k(),idcg_at_k(),reciprocal_rank(),mean_reciprocal_rank()
Key design: Generic, reusable metrics with no API integration
Impact: Metrics ready for offline experiments and production monitoring
- Created
experiments/compare_ranking_methods.pywith:- Synthetic data generation (10 schemes, 100 users)
- Three ranking methods: rule-based, ML, hybrid
- Offline evaluation using ranking metrics
- Results saved to
results.csv - Console output with comparison table
Results Generated:
| Metric | Rule-Based | ML-Based | Hybrid |
|---|---|---|---|
| NDCG@5 | 0.7404 | 0.7700 (+2.96%) | 0.7404 |
| Precision@5 | 0.4725 | 0.5043 (+3.18%) | 0.4725 |
| MAP | 0.7272 | 0.7510 (+2.38%) | 0.7272 |
| MRR | 0.7012 | 0.7077 (+0.65%) | 0.7012 |
Impact: Demonstrates ML value with measured metrics; shows ~3% improvement over rule-based baseline
- Created
src/evaluation/fairness_metrics.pywith:demographic_parity(): Recommendation rates per demographic groupparity_gap(): Maximum difference in rates across groupsrepresentation_variance(): Distribution consistency of top-k recommendationsfairness_report(): Comprehensive analysis across multiple demographicsfairness_summary(): Human-readable output with ⚠ warnings
Design: Analysis-only (no constraints enforced)
Impact: Governance teams can detect demographic bias and make policy decisions
- Added "Evaluation & Results" section with:
- Experimental setup description
- Results summary table (NDCG@5, Precision@5, MAP, MRR)
- Interpretation of findings (+3% ML improvement)
- Honest limitations:
- Synthetic data (not real feedback)
- Small dataset size
- Hand-crafted features
- No distribution shift simulation
- Instructions to reproduce experiment
- Fairness analysis explanation
- Key takeaways (5 bullets)
Tone: Academic, resume-safe, no marketing language
Impact: Results are now credible and defensible in interviews
policy-recommender-ai/
├── README.md (updated: reframed + results section)
├── results.csv (experiment output)
├── src/
│ └── evaluation/
│ ├── __init__.py
│ ├── ranking_metrics.py (NDCG, Precision@k, MAP)
│ └── fairness_metrics.py (demographic parity, variance)
└── experiments/
└── compare_ranking_methods.py (offline experiment script)
- Positioning: Now an "ML-first" system with fairness analysis
- Credibility: Metrics-based evaluation replaces decorative ML claims
- Differentiation: Fairness analysis as unique strength
- Governance: Analysis-only approach appeals to compliance teams
- Interview-Ready: Honest limitations and real results build trust
cd policy-recommender-ai
conda activate ai
python -m experiments.compare_ranking_methodsGenerates:
- Console comparison table
results.csvwith per-user rankings
- Run fairness analysis on experiment output (add to script)
- Integrate evaluation metrics into API for production monitoring
- A/B test on real historical data (not included per requirements)
- Automate experiment runs as CI/CD pipeline
All 5 prompts completed without modifying any existing Python functionality. Documentation-driven ML reframing complete. ✅