“…For the task of AS2, initial efforts embedded the question and candidates using CNNs (Severyn and Moschitti, 2015), weight aligned networks (Shen et al, 2017;Tran et al, 2018;Tay et al, 2018) and compare-aggregate architectures (Wang and Jiang, 2016;Bian et al, 2017;Yoon et al, 2019). Recent progress has stemmed from the application of transformer models for performing AS2 (Garg et al, 2020;Han et al, 2021;Lauriola and Moschitti, 2021). On the data front, small datasets like TrecQA (Wang et al, 2007) and WikiQA (Yang et al, 2015) have been supplemented with datasets such as ASNQ (Garg et al, 2020) having several million QA pairs.…”