Recommender Systems: Machine Learning Metrics and Business Metrics

Recommender systems are designed to suggest relevant content or products to users and can be evaluated using a variety of metrics that cater to both machine learning and business objectives. The systems rely on data-driven approaches, often utilizing machine learning algorithms, with two primary stages: candidate generation and scoring. There are several strategies for building these systems, including global, contextual, and personalized recommendations, each varying in data requirements. Evaluation metrics differ based on the approach, with content-based filtering often using similarity metrics and collaborative filtering employing predictive metrics. Additionally, recommender systems must also consider non-accuracy-related metrics such as diversity, novelty, and trustworthiness, which are crucial for user satisfaction. Business metrics like click-through rates, conversion, and sales impact are typically assessed through A/B testing to align the system's performance with company goals. Ultimately, the balance between machine learning metrics and user-centric and business outcomes determines the success of a recommender system.