Machine Comprehension with Discourse Relations

Karthik Narasimhan and Regina Barzilay


Abstract

This paper proposes a novel approach for incorporating discourse information into machine comprehension applications. Traditionally, such information is computed using off-the-shelf discourse analyzers. This design provides limited opportunities for guiding the discourse parser based on the requirements of the target task. In contrast, our model induces relations between sentences while optimizing a task-specific objective. This approach enables the model to benefit from discourse information without relying on explicit annotations of discourse structure during training. The model jointly identifies relevant sentences, establishes relations between them and predicts an answer. We implement this idea in a discriminative framework with hidden variables that capture relevant sentences and relations unobserved during training. Our experiments demonstrate that the discourse aware model outperforms state-of-the-art machine comprehension systems.