Search papers, labs, and topics across Lattice.
This paper introduces Global Expert Mapping (GEM), a planner-compiler framework for multi-domain learning that replaces the learned router in Mixture-of-Experts (MoE) models with a global scheduler based on linear programming. GEM optimizes for domain-aware routing by computing a fractional assignment of datasets to experts, then uses hierarchical rounding to create a deterministic mapping, avoiding the balancing loss that hinders specialization in standard MoEs. Experiments on UODB demonstrate that GEM-DINO achieves state-of-the-art performance, particularly on underrepresented datasets and in few-shot adaptation.
Ditch the learned router: a global scheduler for Mixture-of-Experts models unlocks state-of-the-art multi-domain learning by explicitly optimizing dataset-to-expert assignments.
Human perception generalizes well across different domains, but most vision models struggle beyond their training data. This gap motivates multi-dataset learning, where a single model is trained on diverse datasets to improve robustness under domain shifts. However, unified training remains challenging due to inconsistencies in data distributions and label semantics. Mixture-of-Experts (MoE) models provide a scalable solution by routing inputs to specialized subnetworks (experts). Yet, existing MoEs often fail to specialize effectively, as their load-balancing mechanisms enforce uniform input distribution across experts. This fairness conflicts with domain-aware routing, causing experts to learn redundant representations, and reducing performance especially on rare or out-of-distribution domains. We propose GEM (Global Expert Mapping), a planner-compiler framework that replaces the learned router with a global scheduler. Our planner, based on linear programming relaxation, computes a fractional assignment of datasets to experts, while the compiler applies hierarchical rounding to convert this soft plan into a deterministic, capacity-aware mapping. Unlike prior MoEs, GEM avoids balancing loss, resolves the conflict between fairness and specialization, and produces interpretable routing. Experiments show that GEM-DINO achieves state-of-the-art performance on the UODB benchmark, with notable gains on underrepresented datasets and solves task interference in few-shot adaptation scenarios.