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 new method 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.