Learning to Learn with Contrastive Meta-Objective

Yatao Bian (National University of Singapore) · Shiguang Wu (Tsinghua University) · Yaqing Wang (Beijing Institute of Mathematical Sciences and Applications) · Quanming Yao (Tsinghua University)
alignmentconmlcontrastive meta-objectivediscrimination abilityfast learninggeneralizabilityimplementation costin-context learninglearner-agnosticmeta-learningmeta-trainingmini-batch episodic trainingmodel representationsperformance optimizationproblem-agnostictask identity

Meta-learning enables learning systems to adapt quickly to new tasks, similar to humans. Different meta-learning approaches all work under/with the mini-batch episodic training framework. Such framework naturally gives the information about task identity, which can serve as additional supervision for meta-training to improve generalizability. We propose to exploit task identity as additional supervision in meta-training, inspired by the alignment and discrimination ability which is is intrinsic in human's fast learning. This is achieved by contrasting what meta-learners learn, i.e., model representations. The proposed ConML is evaluating and optimizing the contrastive meta-objective under a problem- and learner-agnostic meta-training framework. We demonstrate that ConML integrates seamlessly with existing meta-learners, as well as in-context learning models, and brings significant boost in performance with small implementation cost.