EEE-QA: Exploring Effective and Efficient Question-Answer
  Representations
Zhanghao Hu Yijun Yang Junjie Xu Yifu Qiu Pinzhen Chen
Current approaches to question answering rely on pre-trained language models
(PLMs) like RoBERTa. This work challenges the existing question-answer encoding
convention and explores finer representations. We begin with testing various
pooling methods compared to using the begin-of-sentence token as a question
representation for better quality. Next, we explore opportunities to
simultaneously embed all answer candidates with the question. This enables
cross-reference between answer choices and improves inference throughput via
reduced memory usage. Despite their simplicity and effectiveness, these methods
have yet to be widely studied in current frameworks. We experiment with
different PLMs, and with and without the integration of knowledge graphs.
Results prove that the memory efficacy of the proposed techniques with little
sacrifice in performance. Practically, our work enhances 38-100% throughput
with 26-65% speedups on consumer-grade GPUs by allowing for considerably larger
batch sizes. Our work sends a message to the community with promising
directions in both representation quality and efficiency for the
question-answering task in natural language processing.