Towards the Mitigation of Confirmation Bias in Semi-supervised Learning: a Debiased Training Perspective
- URL: http://arxiv.org/abs/2409.18316v1
- Date: Thu, 26 Sep 2024 21:50:30 GMT
- Title: Towards the Mitigation of Confirmation Bias in Semi-supervised Learning: a Debiased Training Perspective
- Authors: Yu Wang, Yuxuan Yin, Peng Li,
- Abstract summary: Semi-supervised learning (SSL) commonly exhibits confirmation bias, where models disproportionately favor certain classes.
We introduce TaMatch, a unified framework for debiased training in SSL.
We show that TaMatch significantly outperforms existing state-of-the-art methods across a range of challenging image classification tasks.
- Score: 6.164100243945264
- License: http://creativecommons.org/licenses/by-nc-sa/4.0/
- Abstract: Semi-supervised learning (SSL) commonly exhibits confirmation bias, where models disproportionately favor certain classes, leading to errors in predicted pseudo labels that accumulate under a self-training paradigm. Unlike supervised settings, which benefit from a rich, static data distribution, SSL inherently lacks mechanisms to correct this self-reinforced bias, necessitating debiased interventions at each training step. Although the generation of debiased pseudo labels has been extensively studied, their effective utilization remains underexplored. Our analysis indicates that data from biased classes should have a reduced influence on parameter updates, while more attention should be given to underrepresented classes. To address these challenges, we introduce TaMatch, a unified framework for debiased training in SSL. TaMatch employs a scaling ratio derived from both a prior target distribution and the model's learning status to estimate and correct bias at each training step. This ratio adjusts the raw predictions on unlabeled data to produce debiased pseudo labels. In the utilization phase, these labels are differently weighted according to their predicted class, enhancing training equity and minimizing class bias. Additionally, TaMatch dynamically adjust the target distribution in response to the model's learning progress, facilitating robust handling of practical scenarios where the prior distribution is unknown. Empirical evaluations show that TaMatch significantly outperforms existing state-of-the-art methods across a range of challenging image classification tasks, highlighting the critical importance of both the debiased generation and utilization of pseudo labels in SSL.
Related papers
- Unlabeled Debiasing in Downstream Tasks via Class-wise Low Variance Regularization [13.773597081543185]
We introduce a novel debiasing regularization technique based on the class-wise variance of embeddings.
Our method does not require attribute labels and targets any attribute, thus addressing the shortcomings of existing debiasing methods.
arXiv Detail & Related papers (2024-09-29T03:56:50Z) - Model Debiasing by Learnable Data Augmentation [19.625915578646758]
This paper proposes a novel 2-stage learning pipeline featuring a data augmentation strategy able to regularize the training.
Experiments on synthetic and realistic biased datasets show state-of-the-art classification accuracy, outperforming competing methods.
arXiv Detail & Related papers (2024-08-09T09:19:59Z) - Editable Fairness: Fine-Grained Bias Mitigation in Language Models [52.66450426729818]
We propose a novel debiasing approach, Fairness Stamp (FAST), which enables fine-grained calibration of individual social biases.
FAST surpasses state-of-the-art baselines with superior debiasing performance.
This highlights the potential of fine-grained debiasing strategies to achieve fairness in large language models.
arXiv Detail & Related papers (2024-08-07T17:14:58Z) - Twice Class Bias Correction for Imbalanced Semi-Supervised Learning [59.90429949214134]
We introduce a novel approach called textbfTwice textbfClass textbfBias textbfCorrection (textbfTCBC)
We estimate the class bias of the model parameters during the training process.
We apply a secondary correction to the model's pseudo-labels for unlabeled samples.
arXiv Detail & Related papers (2023-12-27T15:06:36Z) - Semi-Supervised Class-Agnostic Motion Prediction with Pseudo Label
Regeneration and BEVMix [59.55173022987071]
We study the potential of semi-supervised learning for class-agnostic motion prediction.
Our framework adopts a consistency-based self-training paradigm, enabling the model to learn from unlabeled data.
Our method exhibits comparable performance to weakly and some fully supervised methods.
arXiv Detail & Related papers (2023-12-13T09:32:50Z) - Progressive Feature Adjustment for Semi-supervised Learning from
Pretrained Models [39.42802115580677]
Semi-supervised learning (SSL) can leverage both labeled and unlabeled data to build a predictive model.
Recent literature suggests that naively applying state-of-the-art SSL with a pretrained model fails to unleash the full potential of training data.
We propose to use pseudo-labels from the unlabelled data to update the feature extractor that is less sensitive to incorrect labels.
arXiv Detail & Related papers (2023-09-09T01:57:14Z) - Delving into Identify-Emphasize Paradigm for Combating Unknown Bias [52.76758938921129]
We propose an effective bias-conflicting scoring method (ECS) to boost the identification accuracy.
We also propose gradient alignment (GA) to balance the contributions of the mined bias-aligned and bias-conflicting samples.
Experiments are conducted on multiple datasets in various settings, demonstrating that the proposed solution can mitigate the impact of unknown biases.
arXiv Detail & Related papers (2023-02-22T14:50:24Z) - Learning to Adapt Classifier for Imbalanced Semi-supervised Learning [38.434729550279116]
Pseudo-labeling has proven to be a promising semi-supervised learning (SSL) paradigm.
Existing pseudo-labeling methods commonly assume that the class distributions of training data are balanced.
In this work, we investigate pseudo-labeling under imbalanced semi-supervised setups.
arXiv Detail & Related papers (2022-07-28T02:15:47Z) - CMW-Net: Learning a Class-Aware Sample Weighting Mapping for Robust Deep
Learning [55.733193075728096]
Modern deep neural networks can easily overfit to biased training data containing corrupted labels or class imbalance.
Sample re-weighting methods are popularly used to alleviate this data bias issue.
We propose a meta-model capable of adaptively learning an explicit weighting scheme directly from data.
arXiv Detail & Related papers (2022-02-11T13:49:51Z) - Debiased Learning from Naturally Imbalanced Pseudo-Labels for Zero-Shot
and Semi-Supervised Learning [27.770473405635585]
This work studies the bias issue of pseudo-labeling, a natural phenomenon that widely occurs but often overlooked by prior research.
We observe heavy long-tailed pseudo-labels when a semi-supervised learning model FixMatch predicts labels on the unlabeled set even though the unlabeled data is curated to be balanced.
Without intervention, the training model inherits the bias from the pseudo-labels and end up being sub-optimal.
arXiv Detail & Related papers (2022-01-05T07:40:24Z) - Prototypical Classifier for Robust Class-Imbalanced Learning [64.96088324684683]
We propose textitPrototypical, which does not require fitting additional parameters given the embedding network.
Prototypical produces balanced and comparable predictions for all classes even though the training set is class-imbalanced.
We test our method on CIFAR-10LT, CIFAR-100LT and Webvision datasets, observing that Prototypical obtains substaintial improvements compared with state of the arts.
arXiv Detail & Related papers (2021-10-22T01:55:01Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.