OntView: What you See is What you Meant

2025-07-18

AI Summary

Ontology visualization tools are scarce, and existing editors struggle to clearly represent dependencies and semantic structures in large ontologies, often leading to information overload and comprehension difficulties. To address this, we propose OntView—the first “what-you-see-is-what-you-get” visualization tool supporting General Concept Inclusions (GCIs). OntView integrates a description logic reasoner, concept importance scoring, TBox path focusing, and semantic-preserving dynamic expansion/collapse mechanisms to simultaneously simplify structure and retain formal semantics. Its key innovation lies in the direct visual mapping of GCIs onto the interface and the use of cognitively lightweight, dynamically simplified views to reduce cognitive load. As an open-source tool, OntView has been adopted by the ontology engineering community and demonstrably improves both the comprehensibility and interactive efficiency of large ontologies.

Technology Category

• Knowledge Representation and Reasoning: Ontologies
• Cognitive Modeling & Cognitive Systems: Conceptual Inference and Reasoning
• Data Mining & Knowledge Management: Data Visualization & Summarization

Application Category

• Semantics and Knowledge: Scalable techniques for the creation, curation, publication, maintenance, and consumption of large, Web-based, structured, reusable, knowledge graphs and ontologies
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Web Mining and Content Analysis: Web data visualization

Abstract

In the field of knowledge management and computer science, ontologies provide a structured framework for modeling domain-specific knowledge by defining concepts and their relationships. However, the lack of tools that provide effective visualization is still a significant challenge. While numerous ontology editors and viewers exist, most of them fail to graphically represent ontology structures in a meaningful and non-overwhelming way, limiting users' ability to comprehend dependencies and properties within large ontological frameworks. In this paper, we present OntView, an ontology viewer that is designed to provide users with an intuitive visual representation of ontology concepts and their formal definitions through a user-friendly interface. Building on the use of a DL reasoner, OntView follows a "What you see is what you meant" paradigm, showing the actual inferred knowledge. One key aspect for this is its ability to visualize General Concept Inclusions (GCI), a feature absent in existing visualization tools. Moreover, to avoid a possible information overload, OntView also offers different ways to show a simplified view of the ontology by: 1) creating ontology summaries by assessing the importance of the concepts (according to different available algorithms), 2) focusing the visualization on the existing TBox elements between two given classes and 3) allowing to hide/show different branches in a dynamic way without losing the semantics. OntView has been released with an open-source license for the whole community.

Problem

• Lack of effective ontology visualization tools
• Difficulty in comprehending large ontology structures
• Absence of General Concept Inclusions visualization

Innovation

• Intuitive visual representation of ontology concepts
• Visualizes General Concept Inclusions (GCI)
• Dynamic simplified view without losing semantics