arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2303.01099cs.CVcs.AI
收藏

多头多损失模型校正

Multi-Head Multi-Loss Model Calibration

Universitat Pompeu Fabra(庞培法布拉大学);University of Adelaide(阿德莱德大学);University of Surrey(萨里大学);Catalan Institution for Research and Advanced Studies(加泰罗尼亚研究与高等研究院)

Adrian Galdran, Johan Verjans, Gustavo Carneiro, Miguel A. González Ballester

摘要:

提供有意义的不确定性估计对于在临床实践中成功部署机器学习模型至关重要。不确定性量化的一个核心方面是模型返回与模型正确的实际概率完全一致的预测的能力,也称为模型校准。尽管已经提出了许多方法来改进校准,但没有技术可以与训练深度神经网络集合的简单但昂贵的方法相匹配。在本文中,我们介绍了一种简化的集成形式,它绕过了深度集成的昂贵的训练和推理,但它保留了其校准功能。这个想法是用一组头部来取代网络末端的常见线性分类器,这些头部用不同的损失函数来监督,以加强其预测的多样性。具体来说,每个头部都经过训练以最小化加权交叉熵损失,但不同分支之间的权重不同。我们表明,所得到的平均预测可以实现良好的校准,而不会牺牲准确性,在两个具有挑战性的数据集的组织病理学和内窥镜图像分类。我们的实验表明,多头多损失分类器本质上是校准良好的,优于其他最近的校准技术,甚至挑战深度集成的性能。可以在\url{https://github.com/agaldran/mhml_calibration}中找到重现我们实验的代码。

英文摘要:

Delivering meaningful uncertainty estimates is essential for a successful deployment of machine learning models in the clinical practice. A central aspect of uncertainty quantification is the ability of a model to return predictions that are well-aligned with the actual probability of the model being correct, also known as model calibration. Although many methods have been proposed to improve calibration, no technique can match the simple, but expensive approach of training an ensemble of deep neural networks. In this paper we introduce a form of simplified ensembling that bypasses the costly training and inference of deep ensembles, yet it keeps its calibration capabilities. The idea is to replace the common linear classifier at the end of a network by a set of heads that are supervised with different loss functions to enforce diversity on their predictions. Specifically, each head is trained to minimize a weighted Cross-Entropy loss, but the weights are different among the different branches. We show that the resulting averaged predictions can achieve excellent calibration without sacrificing accuracy in two challenging datasets for histopathological and endoscopic image classification. Our experiments indicate that Multi-Head Multi-Loss classifiers are inherently well-calibrated, outperforming other recent calibration techniques and even challenging Deep Ensembles' performance. Code to reproduce our experiments can be found at \url{https://github.com/agaldran/mhml_calibration} .

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑