The Information Pathways Hypothesis: Transformers are Dynamic Self-Ensembles

التفاصيل البيبلوغرافية
العنوان: The Information Pathways Hypothesis: Transformers are Dynamic Self-Ensembles
المؤلفون: Hussain, Md Shamim, Zaki, Mohammed J., Subramanian, Dharmashankar
سنة النشر: 2023
المجموعة: Computer Science
مصطلحات موضوعية: Computer Science - Machine Learning, Computer Science - Artificial Intelligence
الوصف: Transformers use the dense self-attention mechanism which gives a lot of flexibility for long-range connectivity. Over multiple layers of a deep transformer, the number of possible connectivity patterns increases exponentially. However, very few of these contribute to the performance of the network, and even fewer are essential. We hypothesize that there are sparsely connected sub-networks within a transformer, called information pathways which can be trained independently. However, the dynamic (i.e., input-dependent) nature of these pathways makes it difficult to prune dense self-attention during training. But the overall distribution of these pathways is often predictable. We take advantage of this fact to propose Stochastically Subsampled self-Attention (SSA) - a general-purpose training strategy for transformers that can reduce both the memory and computational cost of self-attention by 4 to 8 times during training while also serving as a regularization method - improving generalization over dense training. We show that an ensemble of sub-models can be formed from the subsampled pathways within a network, which can achieve better performance than its densely attended counterpart. We perform experiments on a variety of NLP, computer vision and graph learning tasks in both generative and discriminative settings to provide empirical evidence for our claims and show the effectiveness of the proposed method.
Comment: KDD23 preprint, 12 pages, 7 figures, 10 tables
نوع الوثيقة: Working Paper
DOI: 10.1145/3580305.3599520
URL الوصول: http://arxiv.org/abs/2306.01705
رقم الانضمام: edsarx.2306.01705
قاعدة البيانات: arXiv