arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2510.08855cs.LGcs.AIcs.CL
收藏

时间感知特征选择:用于稳定稀疏自编码器训练的自适应时间掩码

Time-Aware Feature Selection: Adaptive Temporal Masking for Stable Sparse Autoencoder Training

Yale University(耶鲁大学);University of Chicago(芝加哥大学)

T. Ed Li, Junyu Ren

AI总结:

针对稀疏自编码器训练中的特征吸收问题,提出自适应时间掩码(ATM)方法,通过动态重要性分数与概率掩码实现稳定特征选择,在Gemma-2-2b上显著降低吸收分数并保持重构质量。

摘要:

理解大型语言模型的内部表示对于确保其可靠性和安全性至关重要,而稀疏自编码器(SAEs)已成为一种有前景的可解释性方法。然而,当前的SAE训练方法面临特征吸收问题,即特征(或神经元)为了最小化$L_1$惩罚而相互吸收,这使得一致地识别和分析模型行为变得困难。我们引入了自适应时间掩码(ATM),这是一种新颖的训练方法,通过跟踪激活幅度、频率和重构贡献来动态调整特征选择,以计算随时间演化的重要性分数。ATM基于这些重要性分数的统计阈值应用概率掩码机制,从而形成更自然的特征选择过程。通过在Gemma-2-2b模型上的大量实验,我们证明与现有方法(如TopK和JumpReLU SAEs)相比,ATM实现了显著更低的吸收分数,同时保持了出色的重构质量。这些结果确立了ATM作为学习神经网络中稳定、可解释特征的原则性解决方案,为更可靠的模型分析奠定了基础。

英文摘要:

Understanding the internal representations of large language models is crucial for ensuring their reliability and safety, with sparse autoencoders (SAEs) emerging as a promising interpretability approach. However, current SAE training methods face feature absorption, where features (or neurons) are absorbed into each other to minimize $L_1$ penalty, making it difficult to consistently identify and analyze model behaviors. We introduce Adaptive Temporal Masking (ATM), a novel training approach that dynamically adjusts feature selection by tracking activation magnitudes, frequencies, and reconstruction contributions to compute importance scores that evolve over time. ATM applies a probabilistic masking mechanism based on statistical thresholding of these importance scores, creating a more natural feature selection process. Through extensive experiments on the Gemma-2-2b model, we demonstrate that ATM achieves substantially lower absorption scores compared to existing methods like TopK and JumpReLU SAEs, while maintaining excellent reconstruction quality. These results establish ATM as a principled solution for learning stable, interpretable features in neural networks, providing a foundation for more reliable model analysis.

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。

↑