• inverse document frequency
  • Inverse of the word’s document frequency df (document frequency)
  • Used in tf-idf.
    • It is common to take log
    • Implications are unclear.
      • Some people say “it’s the amount of information,” but I don’t see the point in multiplying it by log(TF).

This page is auto-translated from /nishio/IDF using DeepL. If you looks something interesting but the auto-translated English is not good enough to understand it, feel free to let me know at @nishio_en. I’m very happy to spread my thought to non-Japanese readers.