(m2u)
| 77 | |
| 78 | |
| 79 | def get_loss(m2u): |
| 80 | # d: movie_id -> (user_ids, ratings) |
| 81 | N = 0. |
| 82 | sse = 0 |
| 83 | for j, (u_ids, r) in m2u.items(): |
| 84 | p = W[u_ids].dot(U[j]) + b[u_ids] + c[j] + mu |
| 85 | delta = p - r |
| 86 | sse += delta.dot(delta) |
| 87 | N += len(r) |
| 88 | return sse / N |
| 89 | |
| 90 | |
| 91 |