Inverted Index
Learned in CS451.
A posting is a record that associates a specific word (or term) with a set of documents in which that word appears.
Terminology:
- Inverted Index: maps terms → documents.
- Forward Index: maps documents → terms. (Seems strange, so a book’s index is “inverted”?)
- so the word is simply a mapped to in which document it is in
Postings size follows Zipf’s Law:
- A few terms occur very frequently
- Many terms occur very infrequently
- Like the 80-20 Rule
Instead of using that structure, use a linked list.
