HapPenIng: Happen, Predict, Infer -- Event Series Completion in a Knowledge Graph
This addresses incomplete event representations in semantic sources like Wikidata for societal areas such as sports and politics, but it is incremental as it builds on existing knowledge graph methods.
The paper tackles the problem of event series completion in knowledge graphs by predicting sub-event relations and inferring missing real-world events, achieving precision improvements of 44 and 52 percentage points over baselines.
Event series, such as the Wimbledon Championships and the US presidential elections, represent important happenings in key societal areas including sports, culture and politics. However, semantic reference sources, such as Wikidata, DBpedia and EventKG knowledge graphs, provide only an incomplete event series representation. In this paper we target the problem of event series completion in a knowledge graph. We address two tasks: 1) prediction of sub-event relations, and 2) inference of real-world events that happened as a part of event series and are missing in the knowledge graph. To address these problems, our proposed supervised HapPenIng approach leverages structural features of event series. HapPenIng does not require any external knowledge - the characteristics making it unique in the context of event inference. Our experimental evaluation demonstrates that HapPenIng outperforms the baselines by 44 and 52 percentage points in terms of precision for the sub-event prediction and the inference tasks, correspondingly.