Task Calibration for Distributional Uncertainty in Few-Shot Classification
Authors: Sungnyun Kim, Se-Young Yun
Keywords: few-shot learning, meta-learning, uncertainty estimation
Abstract: As numerous meta-learning algorithms improve performance when solving few-shot classification problems for practical applications, accurate prediction of uncertainty, though challenging, has been considered essential. In this study, we contemplate modeling uncertainty in a few-shot classification framework and propose a straightforward method that appropriately predicts task uncertainty. We suppose that the random sampling of tasks can generate those in which it may be hard for the model to infer the queries from the support examples. Specifically, measuring the distributional mismatch between support and query sets via class-wise similarities, we propose novel meta-training that lets the model predict with careful confidence. Moreover, our method is algorithm-agnostic and readily expanded to include a range of meta-learning models. Through extensive experiments including dataset shift, we present that our training strategy helps the model avoid being indiscriminately confident, and thereby, produce calibrated classification results without the loss of accuracy.