Group-realizable multi-group learning by minimizing empirical risk

2026-01-23

AI Summary

This work addresses the challenge of high sample complexity in multi-group learning under the agnostic setting, particularly when the group family is infinite, which typically undermines generalization guarantees. Focusing instead on the group-realizable setting, the paper provides the first analysis showing that empirical risk minimization (ERM) can achieve significantly reduced sample complexity—even with an infinite group family—provided its VC dimension is finite. The study further demonstrates that standard ERM is computationally infeasible in this context and proposes an efficient alternative based on improper learning. By establishing tighter upper bounds on sample complexity while maintaining theoretical rigor, this work offers both improved theoretical understanding and a practical algorithmic pathway for multi-group learning.

Technology Category

• Machine Learning: Learning Theory
• Multiagent Systems: Multiagent Learning
• Computer Vision: Learning & Optimization for CV

Application Category

• Graph Algorithms and Modeling for the Web: Algorithms and analysis for incomplete, noisy, or partially observed Web-related graphs
• Search and Retrieval-Augmented AI: Web learning to rank, online learning, and counterfactual learning for ranking
• Economics, Online Markets and Human Computation: Fairness, privacy, and diversity in economic environments

Abstract

The sample complexity of multi-group learning is shown to improve in the group-realizable setting over the agnostic setting, even when the family of groups is infinite so long as it has finite VC dimension. The improved sample complexity is obtained by empirical risk minimization over the class of group-realizable concepts, which itself could have infinite VC dimension. Implementing this approach is also shown to be computationally intractable, and an alternative approach is suggested based on improper learning.

Problem

• multi-group learning
• group-realizable
• sample complexity
• VC dimension
• empirical risk minimization

Innovation

• group-realizable learning
• multi-group learning
• sample complexity
• empirical risk minimization
• improper learning