Improving Class and Group Imbalanced Classification with Uncertainty-Based Active Learning

Abstract

Recent experimental and theoretical analyses have revealed that uncertainty-based active learning algorithms (U-AL) are often not able to improve the average accuracy compared to even the simple baseline of passive learning (PL). However, we show in this work that U-AL is a competitive method in problems with severe data imbalance, when instead of the \emph{average} accuracy, the focus is the \emph{worst-subpopulation} accuracy. We show in extensive experiments that U-AL outperforms algorithms that explicitly aim to improve worst-subpopulation performance such as reweighting. We provide insights that explain the good performance of U-AL and show a theoretical result that is supported by our experimental observations.

Cite

Text

Tifrea et al. "Improving Class and Group Imbalanced Classification with Uncertainty-Based Active Learning." NeurIPS 2023 Workshops: ReALML, 2023.

Markdown

[Tifrea et al. "Improving Class and Group Imbalanced Classification with Uncertainty-Based Active Learning." NeurIPS 2023 Workshops: ReALML, 2023.](https://mlanthology.org/neuripsw/2023/tifrea2023neuripsw-improving/)

BibTeX

@inproceedings{tifrea2023neuripsw-improving,
  title     = {{Improving Class and Group Imbalanced Classification with Uncertainty-Based Active Learning}},
  author    = {Tifrea, Alexandru and Hill, John and Yang, Fanny},
  booktitle = {NeurIPS 2023 Workshops: ReALML},
  year      = {2023},
  url       = {https://mlanthology.org/neuripsw/2023/tifrea2023neuripsw-improving/}
}