What is an inverted index?
An inverted index is an alphabetical list of all the words that occur in all documents in a document set. Each word in the list is hooked to every document that contains that word. When the user searches for “light bulb,” the inverted index points to all documents containing either or both of those words. It will, therefore, bring up documents pertaining to “light years” as well as “daffodil bulbs.” It will not retrieve documents on the basis of “incandescent” or “fluorescent tubes.” M.A.I., however, can interpret and index those references as “light bulbs” and place that tag in the document’s metadata, making the document retrievable despite the absence of those query words.
