Competency Questions (CQs) are widely used in ontology development by guiding, among others, the scoping and validation stages. However, very limited guidance exists for formulating CQs and assessing whether they are good CQs, leading to issues such as ambiguity and unusable formulations. To solve this, one requires insight into the nature of CQs for ontologies and their constituent parts, as well as which ones are not. We aim to contribute to such theoretical foundations in this paper, which is informed by analysing questions, their uses, and the myriad of ontology development tasks. This resulted in a first Model for Competency Questions, which comprises five main types of CQs, each with a different purpose: Scoping (SCQ), Validating (VCQ), Foundational (FCQ), Relationship (RCQ), and Metaproperty (MpCQ) questions. This model enhances the clarity of CQs and therewith aims to improve on the effectiveness of CQs in ontology development, thanks to their respective identifiable distinct constituent elements. We illustrate and evaluate them with a user story and demonstrate where which type can be used in ontology development tasks. To foster use and research, we created an annotated repository of 438 CQs, the Repository of Ontology Competency QuestionS (ROCQS), incorporating an existing CQ dataset and new CQs and CQ templates, which further demonstrate distinctions among types of CQs.

翻译：能力问题（CQs）在本体开发中被广泛使用，通过指导范围界定和验证等阶段发挥作用。然而，目前对于如何构建CQs以及评估其是否为良好CQs的指导极为有限，这导致了诸如模糊性和不可用表述等问题。为解决这一问题，需要深入理解本体能力问题的本质及其构成要素，以及哪些问题不属于能力问题。本文旨在为此类理论基础做出贡献，通过分析问题本身、其用途以及本体开发中的各种任务，我们提出了首个能力问题模型。该模型包含五种主要类型的CQs，每种类型具有不同的目的：范围界定问题（SCQ）、验证问题（VCQ）、基础问题（FCQ）、关系问题（RCQ）和元属性问题（MpCQ）。该模型通过各自可识别的独特构成要素，增强了CQs的清晰度，从而旨在提高CQs在本体开发中的有效性。我们通过一个用户故事对这些类型进行了说明和评估，并展示了每种类型在本体开发任务中的应用场景。为促进使用和研究，我们创建了一个包含438个CQs的标注库——本体能力问题库（ROCQS），该库整合了现有的CQ数据集以及新的CQs和CQ模板，进一步展示了不同类型CQs之间的区别。