ai-ethics

## What I do - Identify ethical issues in AI systems - Ensure fairness and bias mitigation - Implement transparency and explainability - Design for accountability - Protect privacy in ML systems ## When to use me When building AI/ML systems that make decisions affecting people. ## Ethical AI Framework ### Fairness ```python from typing import List, Dict import numpy as np class FairnessAuditor: """Audit AI systems for fairness""" def __init__(self): self.protected_attributes = ["race", "gender", "age", "disability", "religion"] def calculate_disparate_impact(self, predictions: np.ndarray, sensitive_attr: np.ndarray, threshold: float = 0.8) -> Dict: """Calculate disparate impact ratio""" groups = np.unique(sensitive_attr) if len(groups) < 2: return {"error": "Need multiple groups"} positive_rates = {} for group in groups: mask = sensitive_attr == group positive_rates[group] = predictions[mask].mean() # Calculate impact ratio reference_rate = positive_rates[groups[0]] ratios = {} for group, rate in positive_rates.items(): if reference_rate > 0: ratios[group] = rate / reference_rate return { "positive_rates": positive_rates, "ratios": ratios, "fails_disparate_impact": any(r < threshold for r in ratios.values()) } def calculate_equalized_odds(self, predictions: np.ndarray, labels: np.ndarray, sensitive_attr: np.ndarray) -> Dict: """Check equalized odds (true positive rate equality)""" groups = np.unique(sensitive_attr) tpr_by_group = {} fpr_by_group = {} for group in groups: mask = sensitive_attr == group tp = ((predictions == 1) & (labels == 1) & mask).sum() fp = ((predictions == 1) & (labels == 0) & mask).sum() tn = ((predictions == 0) & (labels == 0) & mask).sum() fn = ((predictions == 0) & (labels == 1) & mask).sum() tpr_by_group[group] = tp / (tp + fn) if (tp + fn) > 0 else 0 fpr_by_group[group] = fp / (fp + tn) if (fp + tn) > 0 else 0 return { "true_positive_rates": tpr_by_group, "false_positive_rates": fpr_by_group, "equalized": self._check_equalized(tpr_by_group, fpr_by_group) } def mitigate_bias(self, model, X: np.ndarray, sensitive_attr: np.ndarray, method: str = "reweighting") -> np.ndarray: """Apply bias mitigation technique""" if method == "reweighting": return self._reweighting_mitigation(X, sensitive_attr) elif method == "threshold": return self._threshold_adjustment(X, sensitive_attr) else: raise ValueError(f"Unknown method: {method}") def _reweighting_mitigation(self, X, sensitive_attr) -> np.ndarray: """Reweighting-based fairness intervention""" # Compute weights to equalize outcomes return X # Simplified ``` ### Transparency and Explainability ```python class ModelExplainer: """Explain model predictions""" def __init__(self, model): self.model = model def explain_prediction(self, instance: np.ndarray, method: str = "shap") -> Dict: """Explain individual prediction""" if method == "shap": return self._shap_explanation(instance) elif method == "lime": return self._lime_explanation(instance) elif method == "feature_importance": return self._feature_importance_explanation(instance) def _feature_importance_explanation(self, instance: np.ndarray) -> Dict: """Global feature importance explanation""" if hasattr(self.model, "feature_importances_"): importances = self.model.feature_importances_ return { "method": "feature_importance", "importances": importances.tolist(), "top_features": np.argsort(importances)[-5:][::-1].tolist() } return {"error": "Model does not support feature importance"} def generate_model_cards(self, model, training_data: Dict, performance: Dict) -> Dict: """Generate model documentation (model card)""" return { "model_name": model.__class__.__name__, "overview": "Description of model purpose", "owner": "Team responsible", "training_data": { "dataset": training_data.get("name"), "size": training_data.get("size"), "sources": training_data.get("sources") }, "performance": { "metrics": performance.get("metrics"), "evaluation_data": performance.get("test_size") }, "fairness": { "evaluated_groups": [], "known_biases": [] }, "limitations": "Known model limitations", "use_cases": "Intended use cases", "caveats": "Additional caveats" } ``` ### Accountability ```python class AIAccountability: """Ensure AI system accountability""" def __init__(self): self.audit_trail = [] def log_decision(self, decision_id: str, input_data: Dict, prediction: Any, model_version: str, user_id: str = None): """Log AI decision for accountability""" entry = { "decision_id": decision_id, "timestamp": datetime.now().isoformat(), "input_data_hash": hash(str(input_data)), "prediction": prediction, "model_version": model_version, "user_id": user_id, "ip_address": get_client_ip() } self.audit_trail.append(entry) self._write_to_immutable_store(entry) def generate_audit_report(self, start_date: datetime, end_date: datetime) -> Dict: """Generate audit report for date range""" relevant_entries = [ e for e in self.audit_trail if start_date <= e["timestamp"] <= end_date ] return { "total_decisions": len(relevant_entries), "unique_users": len(set(e["user_id"] for e in relevant_entries)), "model_versions": set(e["model_version"] for e in relevant_entries), "predictions_by_outcome": self._count_outcomes(relevant_entries) } def implement_human_oversight(self, prediction: Any, threshold: float = 0.8) -> Dict: """Determine if human review is needed""" confidence = prediction.get("confidence", 1.0) return { "requires_human_review": confidence < threshold, "confidence": confidence, "threshold": threshold, "review_reason": "Low confidence" if confidence < threshold else None } ``` ### Privacy Protection ```python class PrivacyProtection: """Privacy-preserving ML techniques""" def apply_differential_privacy(self, gradients: np.ndarray, epsilon: float = 1.0) -> np.ndarray: """Add noise for differential privacy""" sensitivity = np.max(np.linalg.norm(gradients, axis=1)) noise = np.random.laplace(0, sensitivity / epsilon, gradients.shape) return gradients + noise def anonymize_data(self, data: pd.DataFrame, quasi_identifiers: List[str], sensitive_attributes: List[str]) -> pd.DataFrame: """Apply k-anonymity""" # Generalize quasi-identifiers for col in quasi_identifiers: data[col] = self._generalize(data[col], col) return data def _generalize(self, series, col_name): """Generalize values for k-anonymity""" if col_name == "age": return pd.cut(series, bins=[0, 18, 30, 45, 60, 100], labels=["0-17", "18-29", "30-44", "45-59", "60+"]) return series ```