Extracting the significant-rare keywords for patent analysis

Brainstorming for keywords is used in retrieving patent documents, but even experienced engineers are irresolute in dealing with this critical issue. The quality of a patent report is usually already determined by the keywords they used in the first step. In order to improve the stumbling stone, this paper demonstrates a newmethod of how to find the significant-rare in a patent database. The results show that a systematic patent search (snowball-rolling-procedure) could consider the heterogeneous terms used by assignees, attorneys, and inventors that include some hidden information. Overall, the reliability of patent data can be ameliorated further. 2008 Elsevier Ltd. All rights reserved.