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Related papers: Positive Unlabeled Contrastive Learning

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We consider a problem of learning a binary classifier only from positive data and unlabeled data (PU learning) and estimating the class-prior in unlabeled data under the case-control scenario. Most of the recent methods of PU learning…

Machine Learning · Computer Science 2018-09-18 Masahiro Kato , Liyuan Xu , Gang Niu , Masashi Sugiyama

Learning from positive and unlabeled data (PU learning) is a weakly supervised variant of binary classification in which the learner receives labels only for (some) positively labeled instances, while all other examples remain unlabeled.…

Machine Learning · Computer Science 2026-02-03 Farnam Mansouri , Sandra Zilles , Shai Ben-David

Most of the semi-supervised classification methods developed so far use unlabeled data for regularization purposes under particular distributional assumptions such as the cluster assumption. In contrast, recently developed methods of…

Machine Learning · Computer Science 2017-06-19 Tomoya Sakai , Marthinus Christoffel du Plessis , Gang Niu , Masashi Sugiyama

Learning from positive and unlabeled data or PU learning is the setting where a learner only has access to positive examples and unlabeled data. The assumption is that the unlabeled data can contain both positive and negative examples. This…

Machine Learning · Computer Science 2020-05-19 Jessa Bekker , Jesse Davis

Learning from positive and unlabeled (PU) data is an important problem in various applications. Most of the recent approaches for PU classification assume that the class-prior (the ratio of positive samples) in the training unlabeled…

Machine Learning · Computer Science 2021-12-16 Shota Nakajima , Masashi Sugiyama

From only positive (P) and unlabeled (U) data, a binary classifier could be trained with PU learning, in which the state of the art is unbiased PU learning. However, if its model is very flexible, empirical risks on training data will go…

Machine Learning · Computer Science 2017-11-07 Ryuichi Kiryo , Gang Niu , Marthinus C. du Plessis , Masashi Sugiyama

In PU learning, a binary classifier is trained from positive (P) and unlabeled (U) data without negative (N) data. Although N data is missing, it sometimes outperforms PN learning (i.e., ordinary supervised learning). Hitherto, neither…

Machine Learning · Computer Science 2016-10-31 Gang Niu , Marthinus Christoffel du Plessis , Tomoya Sakai , Yao Ma , Masashi Sugiyama

We present a novel approach to learn binary classifiers when only positive and unlabeled instances are available (PU learning). This problem is routinely cast as a supervised task with label noise in the negative set. We use an ensemble of…

Machine Learning · Statistics 2015-02-13 Marc Claesen , Frank De Smet , Johan A. K. Suykens , Bart De Moor

The problem of learning from positive and unlabeled data (A.K.A. PU learning) has been studied in a binary (i.e., positive versus negative) classification setting, where the input data consist of (1) observations from the positive class and…

Computer Vision and Pattern Recognition · Computer Science 2022-08-29 Omar Zamzam , Haleh Akrami , Richard Leahy

Learning from positive and unlabeled data (PU learning) is actively researched machine learning task. The goal is to train a binary classification model based on a training dataset containing part of positives which are labeled, and…

Machine Learning · Statistics 2023-12-29 Wojciech Rejchel , Paweł Teisseyre , Jan Mielniczuk

When dealing with binary classification of data with only one labeled class data scientists employ two main approaches, namely One-Class (OC) classification and Positive Unlabeled (PU) learning. The former only learns from labeled positive…

Machine Learning · Computer Science 2022-03-15 Farid Bagirov , Dmitry Ivanov , Aleksei Shpilman

As one of the most effective self-supervised representation learning methods, contrastive learning (CL) relies on multiple negative pairs to contrast against each positive pair. In the standard practice of contrastive learning, data…

Machine Learning · Computer Science 2024-01-18 Lu Wang , Chao Du , Pu Zhao , Chuan Luo , Zhangchi Zhu , Bo Qiao , Wei Zhang , Qingwei Lin , Saravan Rajmohan , Dongmei Zhang , Qi Zhang

Learning from positive and unlabeled (PU) data is a setting where the learner only has access to positive and unlabeled samples while having no information on negative examples. Such PU setting is of great importance in various tasks such…

Machine Learning · Computer Science 2022-09-07 Emilio Dorigatti , Jonas Schweisthal , Bernd Bischl , Mina Rezaei

Positive Unlabeled (PU) learning aims to learn a binary classifier from only positive and unlabeled data, which is utilized in many real-world scenarios. However, existing PU learning algorithms cannot deal with the real-world challenge in…

Machine Learning · Computer Science 2022-07-28 Zhongnian Li , Liutao Yang , Zhongchen Ma , Tongfeng Sun , Xinzheng Xu , Daoqiang Zhang

Positive--Unlabeled (PU) learning considers settings in which only positive and unlabeled data are available, while negatives are missing or left unlabeled. This situation is common in real applications where annotating reliable negatives…

Machine Learning · Computer Science 2025-10-30 Miao Zhang , Junpeng Li , Changchun Hua , Yana Yang

Semi-supervised learning is attracting blooming attention, due to its success in combining unlabeled data. However, pseudo-labeling-based semi-supervised approaches suffer from two problems in image classification: (1) Existing methods…

Computer Vision and Pattern Recognition · Computer Science 2024-07-08 Xuerong Zhang , Li Huang , Jing Lv , Ming Yang

Positive-unlabeled learning (PU learning) in hyperspectral remote sensing imagery (HSI) is aimed at learning a binary classifier from positive and unlabeled data, which has broad prospects in various earth vision applications. However, when…

Computer Vision and Pattern Recognition · Computer Science 2025-02-25 Hengwei Zhao , Xinyu Wang , Jingtao Li , Yanfei Zhong

Positive-Unlabeled (PU) learning aims to train a binary classifier (positive vs. negative) where only limited positive data and abundant unlabeled data are available. While widely applicable, state-of-the-art PU learning methods…

Machine Learning · Computer Science 2026-02-11 Hengwei Zhao , Zhengzhong Tu , Zhuo Zheng , Wei Wang , Junjue Wang , Rusty Feagin , Wenzhe Jiao

We propose a new method of learning from positive and unlabeled (PU) examples in highly imbalanced datasets. Many real-world problems, such as disease gene identification, targeted marketing, fraud detection, and recommender systems, are…

Machine Learning · Computer Science 2026-05-15 Elias Zavitsanos , Georgios Paliouras

We address the issue of binary classification from positive and unlabeled data (PU classification) with a selection bias in the positive data. During the observation process, (i) a sample is exposed to a user, (ii) the user then returns the…

Machine Learning · Computer Science 2023-03-09 Masahiro Kato , Shuting Wu , Kodai Kureishi , Shota Yasui