Search in social networks such as Facebook poses different challenges than in classical web search: besides the query text, it is important to take into account the searcher's context to provide relevant results. Their social graph is an integral part of this context and is a unique aspect of Facebook search. While embedding-based retrieval (EBR) has been applied in eb search engines for years, Facebook search was still mainly based on a Boolean matching model. In this paper, we discuss the techniques for applying EBR to a Facebook Search system. We introduce the unified embedding framework developed to model semantic embeddings for personalized search, and the system to serve embedding-based retrieval in a typical search system based on an inverted index. We discuss various tricks and experiences on end-to-end optimization of the whole system, including ANN parameter tuning and full-stack optimization. Finally, we present our progress on two selected advanced topics about modeling. We evaluated EBR on verticals for Facebook Search with significant metrics gains observed in online A/B experiments. We believe this paper will provide useful insights and experiences to help people on developing embedding-based retrieval systems in search engines.
@article{arxiv.2006.11632,
title = {Embedding-based Retrieval in Facebook Search},
author = {Jui-Ting Huang and Ashish Sharma and Shuying Sun and Li Xia and David Zhang and Philip Pronin and Janani Padmanabhan and Giuseppe Ottaviano and Linjun Yang},
journal= {arXiv preprint arXiv:2006.11632},
year = {2020}
}
Comments
9 pages, 3 figures, 3 tables, to be published in KDD '20