Add monitoring and alerting for collaborative filtering model drift

Problem

We deployed the collaborative filtering model but have no monitoring for model performance degradation over time.

Requirements

Model Performance Metrics

• Track Precision@10 in production (daily)
• Monitor recommendation diversity
• Track cold-start coverage (new users/items)
• Alert if precision drops below 80%

Data Quality Metrics

• Monitor interaction data freshness
• Track data volume trends
• Detect anomalies in user behavior

Business Metrics

• Click-through rate (CTR) on recommendations
• Conversion rate from recommendations
• Revenue attribution

Implementation

• Prometheus metrics export
• Grafana dashboards
• PagerDuty integration for alerts
• Weekly model performance reports

Acceptance Criteria

• Metrics exported from recommendation service
• Dashboards created with 7-day trends
• Alerts configured with appropriate thresholds
• Runbook for responding to model drift