Research Article
Detecting Shilling Attacks with Automatic Features from Multiple Views
Algorithm 1
Data preprocessing.
| Input: DR | |
| Output: R, P, M | |
| 1if (item sequence is not updated) then | |
| 2Calculate the novelty of items NIi according to formula (7) | |
| 3Construct the item popularity sequence SQI | |
| 4end if | |
| 8for each do | |
| 9for curi=1 to | |
| 10ui=indexU(curi) | |
| 11R(ui,i)=rate(DR,ui,i) | |
| 12P(ui,i)=NIi | |
| 13for curj= curi+1 to | |
| 14uj=indexU(curj) | |
| 15if ui!=uj then | |
| 16M(ui, uj)=M(ui, uj)+1 | |
| 17M(uj, ui)=M(ui, uj) | |
| 18end if | |
| 19end for | |
| 20end for | |
| 21end for | |
| 22Return R, P, M |