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arXiv · 2106.10711

Transfer Bayesian Meta-learning via Weighted Free Energy Minimization

Yunchuan Zhang·Sharu Theresa Jose·Osvaldo Simeone
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Abstract

Meta-learning optimizes the hyperparameters of a training procedure, such as its initialization, kernel, or learning rate, based on data sampled from a number of auxiliary tasks. A key underlying assumption is that the auxiliary tasks, known as meta-training tasks, share the same generating distribution as the tasks to be encountered at deployment time, known as meta-test tasks. This may, however, not be the case when the test environment differ from the meta-training conditions. To address shifts in task generating distribution between meta-training and meta-testing phases, this paper introduces weighted free energy minimization (WFEM) for transfer meta-learning. We instantiate the proposed approach for non-parametric Bayesian regression and classification via Gaussian Processes (GPs). The method is validated on a toy sinusoidal regression problem, as well as on classification using miniImagenet and CUB data sets, through comparison with standard meta-learning of GP priors as implemented by PACOH.

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Yunchuan Zhang, Sharu Theresa Jose, Osvaldo Simeone. 2021-06-20. Transfer Bayesian Meta-learning via Weighted Free Energy Minimization. https://arxiv.org/abs/2106.10711

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