Word Sense Disambiguation (WSD) is one of the hardest tasks in natural language understanding and knowledge engineering. The glass ceiling of the 80% F1 score is recently achieved through supervised learning, enriched by knowledge graphs. Here, we propose a novel neurosymbolic methodology that may push the F1 score above 90%. The core of our methodology is a neurosymbolic sense embedding, in terms of a configuration of nested n-dimensional balls. The central point of a ball well preserves pre-trained word embeddings learned from data, which partially fixes the locations of balls. Inclusion relations among balls precisely encode symbolic hypernym relations among senses, and enable simple logic deduction among sense embeddings. We trained a Transformer to learn the mapping from a contextualized word embedding to its sense ball embedding, just like playing the game of darts (a game of shooting darts into a dartboard). A series of experiments are carried out using pre-training n ball embeddings, which cover around 70% training data and 75% testing data in the benchmark WSD corpus. Euclidean distance and cosine similarity functions are used as objective functions, separately, and each reaches >95.0% F1 score in the ALL-n-ball dataset. This substantially breaks the glass ceiling of deep learning methods. Future work is discussed to develop a full-fledged neurosymbolic WSD system that substantially outperforms deep learning approaches.

The FinCausal 2020 shared task aims to detect causality on financial news and identify those parts of the causal sentences related to the underlying cause and effect. We apply ensemble-based and sequence tagging methods for identifying causality, and extracting causal subsequences. Our models yield promising results on both sub-tasks, with the prospect of further improvement given more time and computing resources. With respect to task 1, we achieved an F1 score of 0.9429 on the evaluation data, and a corresponding ranking of 12/14. For task 2, we were ranked 6/10, with an F1 score of 0.76 and an ExactMatch score of 0.1912.