The Building Knowledge Graph
RealEstateCore (REC) is an ontology, which can most easily be thought of as a standard and interoperable schema for building knowledge graphs; it defines the types (classes) of nodes you can have in your graph, the types of relations (object properties) these nodes have with one another, and the types of data values (data properties) associated with them. By using REC, you get two distinct advantages:
- You do not need to spend a lot of time and resources on designing your own data model; we’ve already done it for you.
- Your data is automatically compatible with that of other REC users (e.g., your suppliers or your customers), greatly simplifying data and process integration (doubly so if you also utilize the REC APIs to exchange data).
RealEstateCore is used with RDF-based knowledge graphs. There is a wealth of information about RDF available on the net, which we will not duplicate here; suffice to say that in RDF, a knowledge graph is made up of a (potentially very large) set of statements, each of which consist of three components: the subject of the statement, the predicate that captures what the statement intends to say about the subject , and the object that carries the value of that assertion. E.g., a graph might include the statement WhiteHouse ownedBy USGovernment, or IBM hasNumberOfEmployees 345900. Due to their structure, a statement is often known as a triple.
In the below we introduce some key REC classes and exemplify their use with RDF triples.