The input table, ml_ratings, is a collection of movie ratings from 50 users on approximately 2900 movies, with an average of about 150 ratings per user. There are 10 possible ratings, ranging from 0.5 to 5 in steps of 0.5. A higher number indicates a better rating.
| userid | itemid | rating |
|---|---|---|
| 1 | 1 | 5 |
| 1 | 2 | 3 |
| 1 | 10 | 3 |
| 1 | 32 | 4 |
| 1 | 34 | 4 |
| 1 | 47 | 3 |
| 1 | 50 | 4 |
| 1 | 62 | 4 |
| 1 | 150 | 4 |
| 1 | 153 | 3 |
| 1 | 160 | 3 |
| 1 | 161 | 4 |
| 1 | 165 | 4 |
| 1 | 185 | 3 |
| ... | ... | ... |