Inverted Files
Primary data structure for text indexes
Invert documents into a big index
Basic idea:
- list all the tokens in the collection
- for each token, list all the docs it occurs in
- do a few things to reduce redundancy in the data structure
Read “Inverted Files” by Harman et al., Chapter 3, sections 3.1 through 3.3 (the rest of the chapter is optional).