Making Transformers Solve Compositional Tasks
Santiago Ontañón, Joshua Ainslie, Vaclav Cvicek, Zachary Fisher
TL;DR
The paper tackles the problem of Transformer failures in compositional generalization by systematically exploring Transformer design choices to induce inductive biases. It analyzes position encodings, decoder type, model size, weight sharing, and intermediate representations across 12 diverse datasets, all trained from scratch. Key findings include large gains from relative position encodings, copy decoders, and intermediate representations, culminating in state-of-the-art COGS performance (0.784) and strong PCFG results. These results underscore the importance of architecture-aware biases for enabling robust compositional generalization and guide future work on scaling and pre-training.
Abstract
Several studies have reported the inability of Transformer models to generalize compositionally, a key type of generalization in many NLP tasks such as semantic parsing. In this paper we explore the design space of Transformer models showing that the inductive biases given to the model by several design decisions significantly impact compositional generalization. Through this exploration, we identified Transformer configurations that generalize compositionally significantly better than previously reported in the literature in a diverse set of compositional tasks, and that achieve state-of-the-art results in a semantic parsing compositional generalization benchmark (COGS), and a string edit operation composition benchmark (PCFG).
