Thread

1. jll29 · 1790067648 · focus · HN ↗

   Yes: you can classify a test file by topic with gzip as follows:

     gzip -9 sports.txt   testfile.txt
   
     gzip -9 politics.txt testfile.txt
   
     gzip -9 business.txt testfile.txt
   

   (ass. sports.txt politics.txt and business.txt are text docs pertaining from the sports, politics and business domains, respectively, and have equal size)

   The test file belongs to the topic with the smallest size *.gz file.

   Witten's group at Waikato uni were perhaps the first to work on this.

   Also check out the Hutter prize if you are interested in this.

   1. mrtnmcc · 1790106938 · focus · HN ↗

      You might also want the topic files to be compressed against each other to get a baseline matrix and then multiply any results by the inverse, assuming equal priors on the topics.

Unofficial Hacker News client; not affiliated with Y Combinator.