SCoRe: Pre-Training for Context Representation in Conversational Semantic Parsing

Conversational Semantic Parsing (CSP) is the task of converting a sequence of natural language queries to formal language (e.g., SQL, SPARQL) that can be executed against a structured ontology (e.g. databases, knowledge bases). To accomplish this task, a CSP system needs to model the relation between the unstructured language utterance and the structured ontology while representing the multi-turn dynamics of the dialog. Pre-trained language models (LMs) are the state-of-the-art for various natural language processing tasks. However, existing pre-trained LMs that use language modeling training objectives over free-form text have limited ability to represent natural language references to contextual structural data. In this work, we present SCORE, a new pre-training approach for CSP tasks designed to induce representations that capture the alignment between the dialogue flow and the structural context. We demonstrate the broad applicability of SCORE to CSP tasks by combining SCORE with strong base systems on four different tasks (SPARC, COSQL, MWOZ, and SQA). We show that SCORE can improve the performance over all these base systems by a significant margin and achieves state-of-the-art results on three of them. Published as a conference paper at ICLR 2021 Usr: Find the names of the top 3 highest sales books. Usr: Who are their authors? Usr: Also show the names of their publishers. … ... : I am looking for a cheap restaurant in the centre of the city Sys: There is a cheap chinese restaurant called Dojo Noodle Bar. Usr: Yes please , for 8 people at 18:30 on Thursday … ... Usr: I also need to book a taxi between to the restaurant at 20:30. Sys: The taxi is booked. SELECT title FROM book ORDER BY sale_amount DESC LIMIT 3 SELECT t1.title, t1.name FROM author AS t1 JOIN book AS t2 ON t1.id = t2.author_id ORDER BY t2.sale_amount DESC LIMIT 3 SELECT t1.title, t1.name, t3.name FROM author AS t1 JOIN book AS t2 ON t1.id = t2.author_id JOIN press AS t3 ON t2.press_id = t3.id ORDER BY t2.sale_amount DESC LIMIT 3 Restaurant(Price=cheap, area=center)