Google's US 6,941,293 on equivalent descriptions for an information need

First claim of US 6,941,293:

A computer-implemented method for determining equivalent descriptions for an information need, comprising:

identifying a list of queries issued by one or more users;

identifying a candidate pair of equivalent descriptions by locating two queries that refer to the same information need;

calculating a score for the candidate pair dependent on the frequency with which the candidate pair occurs in the list; and

determining that each half of the candidate pair is an equivalent description for the information need if the score calculated for the candidate pair is above a defined threshold value.

Description of Related Art

The World Wide Web ("web") contains a vast amount of information. Locating a desired portion of the information, however, can be challenging. Unless the user is aware of the specific location of the desired information, the user must rely on a service to assist in locating the information. Typically, the user will identify the information sought via a query of some form, and the service will attempt to direct the user to the information based on the query.

Unfortunately, however, the user cannot always formulate the query in a sufficient manner as to obtain all of the information that the user desires. For example, the user may have an information need that can be described in multiple ways, but the user may only be aware of a limited way of describing that information need. In such a case, the user may obtain only a subset of the desired information.

It would be helpful, therefore, to have methods and apparatus for determining equivalent ways of describing an information need.