Leaning on Ontologies

Semantic technology finds better ways of indexing contextually by creating what Moulton calls a “hierarchy of terminology,” which semantics experts call an ontology. “You’ve probably heard of taxonomies, which are just tree-structures of language. An ontology takes it to another level, rather than just having two dimensions─broader and narrower─you have an unlimited number of dimensions of how words or charts are related to each other,” Moulton explains. “I can say a steering wheel is a part of a car, a wheel is a part of a car, and an engine is a part of a car, [but] a carburetor is a part of an engine. That is a broader-narrower concept. If you take it to another dimension and say engines are systems within cars that drive cars forward, and carburetors are one of the components of engines, now, you have a whole new layer of relationships between the words.”

Ontologies create a web of connections that can act as shorthand for the engine users employ to search quickly through information across data sources.

“We have quite a bit of interest from people who have lots of diverse content,” says Polikoff of TopQuadrant. “Let’s say you have a retailer with a catalog of many different items, ranging from refrigerators to carpets to electronics and so on. They need to be able to build this catalog and integrate other sources into it in a quick way. Ontologies can act less rigidly than data structures and this allows us to quickly build the model of their catalog and put data into the model and search quickly.”

This creates a new layer of metadata to make it easier to navigate through the information, Polikoff explains.

“The idea is that you have all these different data sources with different formats, and that’s a problem for people. So you have, let’s call it, the data-sources layer that exists in all kinds of organizations and enterprises,” she says. “This technology allows you to put a new layer on top of that. We can call it the semantic web layer that consists of certain kinds of models that allow one to map these different data sources to a common vocabulary. That gives you the power to provide very rich information spaces of many different sorts on which you can build many different applications.