  In this work, we introduce kernels with random Fourier features in the
meta-learning framework to leverage their strong few-shot learning ability. We
propose meta variational random features (MetaVRF) to learn adaptive kernels
for the base-learner, which is developed in a latent variable model by treating
the random feature basis as the latent variable. We formulate the optimization
of MetaVRF as a variational inference problem by deriving an evidence lower
bound under the meta-learning framework. To incorporate shared knowledge from
related tasks, we propose a context inference of the posterior, which is
established by an LSTM architecture. The LSTM-based inference network can
effectively integrate the context information of previous tasks with
task-specific information, generating informative and adaptive features. The
learned MetaVRF can produce kernels of high representational power with a
relatively low spectral sampling rate and also enables fast adaptation to new
tasks. Experimental results on a variety of few-shot regression and
classification tasks demonstrate that MetaVRF delivers much better, or at least
competitive, performance compared to existing meta-learning alternatives.
