CKBP v2: An Expert-Annotated Evaluation Set for Commonsense Knowledge Base Population

Populating Commonsense Knowledge Bases (CSKB) is an important yet hard task in NLP, as it tackles knowledge from external sources with unseen events and entities. Fang et al. (2021a) proposed a CSKB Population benchmark with an evaluation set CKBP v1. However, CKBP v1 adopts crowdsourced annotations that suffer from a substantial fraction of incorrect answers, and the evaluation set is not well-aligned with the external knowledge source as a result of random sampling. In this paper, we introduce CKBP v2, a new high-quality CSKB Population benchmark, which addresses the two mentioned problems by using experts instead of crowd-sourced annotation and by adding diversified adversarial samples to make the evaluation set more representative. We conduct extensive experiments comparing state-of-the-art methods for CSKB Population on the new evaluation set for future research comparisons. Empirical results show that the population task is still challenging, even for large language models (LLM) such as ChatGPT. Codes and data are available at https://github.com/HKUST-KnowComp/CSKB-Population.