A Benchmark for Gap and Overlap Analysis as a Test of KG Task Readiness

TL;DR

This paper introduces a benchmark for evaluating knowledge graph quality through gap and overlap analysis in policy documents, emphasizing explainability, reproducibility, and evidence-based validation.

Contribution

It provides an executable, auditable benchmark aligning natural language contracts with ontologies and evidence, enabling systematic comparison of different KG analysis methods.

Findings

Ontology-driven approach improves consistency in gap/overlap analysis.

Explicit modeling enhances diagnosis and reliability over text-only methods.

Benchmark supports evaluation of KG quality and downstream tasks.

Abstract

Task-oriented evaluation of knowledge graph (KG) quality increasingly asks whether an ontology-based representation can answer the competency questions that users actually care about, in a manner that is reproducible, explainable, and traceable to evidence. This paper adopts that perspective and focuses on gap and overlap analysis for policy-like documents (e.g., insurance contracts), where given a scenario, which documents support it (overlap) and which do not (gap), with defensible justifications. The resulting gap/overlap determinations are typically driven by genuine differences in coverage and restrictions rather than missing data, making the task a direct test of KG task readiness rather than a test of missing facts or query expressiveness. We present an executable and auditable benchmark that aligns natural-language contract text with a formal ontology and evidence-linked ground truth, enabling systematic comparison of methods. The benchmark includes: (i) ten simplified yet diverse life-insurance contracts reviewed by a domain expert, (ii) a domain ontology (TBox) with an instantiated knowledge base (ABox) populated from contract facts, and (iii) 58 structured scenarios paired with SPARQL queries with contract-level outcomes and clause-level excerpts that justify each label. Using this resource, we compare a text-only LLM baseline that infers outcomes directly from contract text against an ontology-driven pipeline that answers the same scenarios over the instantiated KG, demonstrating that explicit modeling improves consistency and diagnosis for gap/overlap analyses. Although demonstrated for gap and overlap analysis, the benchmark is intended as a reusable template for evaluating KG quality and supporting downstream work such as ontology learning, KG population, and evidence-grounded question answering.