A product or service model is a intangible entity that specifies some characteristics of a group of similar, usually mass-produced products, in the sense of a prototype. In case of mass-produced products, there exists a relation gr:hasMakeAndModel between the actual product or service (gr:Individual or gr:SomeItems) and the prototype (gr:ProductOrServiceModel). GoodRelations treats product or service models as "prototypes" instead of a completely separate kind of entities, because this allows using the same domain-specific properties (e.g. gr:weight) for describing makes and models and for describing actual products.
Examples: Ford T, Volkswagen Golf, Sony Ericsson W123 cell phone
Note: An actual product or service (gr:Individual) by default shares the features of its model (e.g. the weight). However, this requires non-standard reasoning. See http://wiki.goodrelations-vocabulary.org/Axioms for respective rule sets.
Compatibility with schema.org: This class is (approximately) a subclass of http://schema.org/Product.From the ontological perspective, a Product or Service Model is an intangible entity that specifies some characteristics of a group of similar, usually mass-produced Products. In case of mass-produced Products, there exists a relation hasMakeAndModel between the Products and Services Instance and the Product or Service Model.
Since eClassOWL and other products and services ontologies don't support this important disctinction, Product or Service Models are a subclass of Product or Service in GoodRelations. This allows using the same properties for (e.g. "hasWeight") for product models and actual products.
Examples: Ford T, Volkswagen Golf, Sony Ericsson W123 cell phone
Note: An Actual Product or Service Instance of which is known via a relation hasMakeAndModel that it is of a certain Product Or Service Model should by default share the features of this model (e.g. the weight). However, this requires non-standard reasoning. See the GoodRelations Wiki at http://www.ebusiness-unibw.org/wiki/GoodRelations for respective rule sets.