Title
Efficient search over incomplete knowledge graphs in binarized embedding space
Abstract
Knowledge graph (KG) embedding techniques represent entities and relations as low-dimensional and continuous vectors. This enables KG machine learning models to be easily adapted for KG reasoning, completion, and querying tasks. However, learned dense vectors are inefficient for large-scale similarity computations. Learning-to-hash is to a method that learns compact binary codes from high-dimensional input data and provides a promising way to accelerate efficiency by measuring the Hamming distance instead of Euclidean distance. Alternatively, a dot-product is used in a continuous vector space. Unfortunately, most learning-to-hash methods cannot be directly applied to KG structure encoding because they focus on similarity preservation between images. In this paper, we introduce a novel end-to-end learning-to-hash framework for encoding incomplete KGs and graph queries in a Hamming space. To preserve KG structure information, from embeddings to hash codes, and address the ill-posed gradient issue in the optimization, we utilize a continuation method (with convergence guarantees) to jointly encode queries and KG entities using geometric operations. The hashed embedding of a query can be utilized to discover target entities from incomplete KGs whilst the efficiency has been greatly improved. To evaluate the proposed framework, we have compared our model to state-of-the-art methods commonly used in real-world KGs. Extensive experimental results show that our framework not only significantly speeds up the search process, but also provides good results when unanswerable queries are caused by incomplete information.11Our code and data are open in Github https://github.com/seu-kse/HashKG.
Year
DOI
Venue
2021
10.1016/j.future.2021.04.006
Future Generation Computer Systems
Keywords
DocType
Volume
Knowledge graph embedding,Learning to hashing,Graph query
Journal
123
ISSN
Citations 
PageRank 
0167-739X
0
0.34
References 
Authors
10
6
Name
Order
Citations
PageRank
Meng Wang12411.05
weitong chen215513.19
Sen Wang347737.24
Yinlin Jiang400.34
Lina Yao598193.63
Guilin Qi696188.58