In: Advanced Math
Given the following utility matrix, representing the ratings, on a 1–5 star scale, of eight items, a through h, by three users A, B, and C:
a | b | c | d | e | f | g | h | |
A | 4 | 5 | 5 | 1 | 3 | 2 | ||
B | 3 | 4 | 3 | 1 | 2 | 1 | ||
C | 2 | 1 | 3 | 4 | 5 | 3 |
After we normalize the matrix by subtracting from each nonblank entry the average value for its user, what is the cosine distance between users A and C ?
-0.1155 |
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0.5842 |
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0.3334 |
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-0.7396 |