activity
20232026
collaborators

7 papers

cs.LG2026

Partial AUC Maximization from Positive-unlabeled Data

Atsutoshi Kumagai, Tomoharu Iwata, Taishi Nishiyama +3

The partial area under the receiver operating characteristic curve (pAUC) is an important performance metric for binary classification that summarizes true positive rates within a…

cs.LG2026

Importance Weighting for Unlabeled-unlabeled Learning under Distribution Shift

Atsutoshi Kumagai, Tomoharu Iwata, Hiroshi Takahashi +3

Unlabeled-unlabeled (UU) learning allows us to learn a binary classifier from two sets of unlabeled data with different class-priors. It is a general framework because it includes…

cs.LG2026

AUC Maximization from Biased Positive-unlabeled Data with Confidence

Atsutoshi Kumagai, Tomoharu Iwata, Hiroshi Takahashi +3

Maximizing the area under the receiver operating characteristic curve (AUC) is a standard approach to imbalanced binary classification. Although positive and negative data are requ…

cs.CV2026

Cross-device Collaborative Test-time Adaptation with Zeroth-order Optimization and Model Merging

Yu Mitsuzumi, Akisato Kimura, Yasuhiro Fujiwara +1

Test-time adaptation (TTA) mitigates domain shifts by using incoming test data to update a model on the fly. The majority of TTA methods require resource-intensive backpropagation…

cs.LG2025

Meta-learning Representations for Learning from Multiple Annotators

Atsutoshi Kumagai, Tomoharu Iwata, Taishi Nishiyama +2

We propose a meta-learning method for learning from multiple noisy annotators. In many applications such as crowdsourcing services, labels for supervised learning are given by mult…

cs.LG2024

Meta-learning for Positive-unlabeled Classification

Atsutoshi Kumagai, Tomoharu Iwata, Yasuhiro Fujiwara

We propose a meta-learning method for positive and unlabeled (PU) classification, which improves the performance of binary classifiers obtained from only PU data in unseen target t…

cs.LG2023

Fast Regularized Discrete Optimal Transport with Group-Sparse Regularizers

Yasutoshi Ida, Sekitoshi Kanai, Kazuki Adachi +2

Regularized discrete optimal transport (OT) is a powerful tool to measure the distance between two discrete distributions that have been constructed from data samples on two differ…