recommenderlab (version 1.0.6)

Jester5k: Jester dataset (5k sample)

Description

The data set contains a sample of 5000 users from the anonymous ratings data from the Jester Online Joke Recommender System collected between April 1999 and May 2003.

Usage

data(Jester5k)

Format

The format of Jester5k is: Formal class 'realRatingMatrix' [package "recommenderlab"]

The format of JesterJokes is: vector of character strings.

Details

Jester5k contains a 5000 x 100 rating matrix (5000 users and 100 jokes) with ratings between -10.00 and +10.00. All selected users have rated 36 or more jokes.

The data also contains the actual jokes in JesterJokes.

References

Ken Goldberg, Theresa Roeder, Dhruv Gupta, and Chris Perkins. "Eigentaste: A Constant Time Collaborative Filtering Algorithm." Information Retrieval, 4(2), 133-151. July 2001.

Examples

data(Jester5k)
Jester5k

## number of ratings
nratings(Jester5k)

## number of ratings per user
summary(rowCounts(Jester5k))

## rating distribution
hist(getRatings(Jester5k), main="Distribution of ratings")

## 'best' joke with highest average rating
best <- which.max(colMeans(Jester5k))
cat(JesterJokes[best])