Coupling metrics for ontology-based system

Measuring system coupling is a commonly accepted software engineering practice associated with producing high-quality software products. Coupling metrics traditionally measure data passed across a module interface to determine couplings between modules in a given system. XML has become common in Internet-based application domains such as business-to-business and business-to-consumer applications, and has formed a basis for service-oriented architectures such as Web services and the Semantic Web. We therefore need new coupling metrics that address these systems´ unique requirements. We propose a set of coupling metrics for ontology-based systems represented in OWL: the number of external classes (NEC), reference to external classes (REC), and referenced includes (RI). To collect these metrics, we use a standard XML-based parser. This research reflects a new type of coupling measurement for system development that defines coupling metrics based on ontology data and its structure.