Facts in the real world are often tied to time, such as the spread of diseases, and the state of military affairs. Therefore, knowledge graphs combined with temporal factors have gained growing attention. In the temporal knowledge graph, most researchers focus on the original facts and pay attention to their changes over time. The temporal factors are only used as auxiliary information for representation learning. In this paper, we try to observe from the perspective of time and find some interesting properties of temporal knowledge graph: (1) Simultaneousness. Various facts occur at the same time; (2) Aggregation. The facts may aggregately occur for a certain individual, organization, or location; (3) Associativity. Some specific relations tend to occur at specific times, such as celebrations at festivals. Based on the above three properties, we add a simple time-aware module to the existing tensor decomposition-based temporal knowledge graph model TComplEx (Lacroix et al., 2020), which obtains impressive improvements and achieves state-of-the-art results on four standard temporal knowledge graph completion benchmarks. Specifically, in terms of mean reciprocal rank (MRR), we advance the state-of-the-art by +24.0% on ICEWS14, +13.2% on ICEWS05-15, +31.9% on YAGO15k, and 4.7% on GDELT.
Read full abstract