1. Twenty Newsgroups: This data set consists of 20000 messages taken from 20 newsgroups.
2. Entree Chicago Recommendation Data: This data contains a record of user interactions with the Entree Chicago restaurant recommendation system.
3. NSF Research Award Abstracts 1990-2003: This data set consists of (a) 129,000 abstracts describing NSF awards for basic research, (b) bag-of-word data files extracted from the abstracts, (c) a list of words used for indexing the bag-of-word
4. Pseudo Periodic Synthetic Time Series: This data set is designed for testing indexing schemes in time series databases. The data appears highly periodic, but never exactly repeats itself.