Conundrums in Event Coreference Resolution: Making Sense of the State of the Art

Despite recent promising results achieved by span-based approaches to event coreference resolution, there is a lack of understanding of what has been improved. We present an empirical analysis of our state-of-the-art span-based event coreference resolver (Lu and Ng, 2021) with the goal of providing the general NLP audience with a better understanding of the state of the art and coreference researchers with directions for future research.