www-ai.cs.tu-dortmund.de/LEHRE/SEMINARE/MUSIK/2006/Towards%20the%20Next%20Generation%20of%20Recommender%20Systems.pdf
aggregation function are:
ðaÞ rc;s ¼ 1
N
X c02ĈC
rc0;s;
ðbÞ rc;s ¼ k X c02ĈC
simðc; c0Þ rc0;s;
ðcÞ rc;s ¼ rrc þ k X c02ĈC
simðc; c0Þ ðrc0;s rrc0 Þ;
ð10Þ
where multiplier k serves as a normalizing [...] 8ðdj1; . . . ; djlÞ 2 Dj1 . . .Djl;
ðdi1; . . . ; dikÞ ¼ argmax ðd0i1;...;d0ikÞ2Di1...Dik
ðd0j1;...;d0jlÞ¼ðdj1;...;djlÞ
uðd01; . . . ; d0nÞ: ð20Þ
For example, in the case of a movie recommender system, one [...] measure between users c and c0,
simðc; c0Þ, is essentially a distance measure and is used as a weight, i.e., the more similar users c and c0 are, the more weight rating rc0;s will carry in the prediction …
