Given the (cosine) similarity score of top 100 neighbors of every item, how do I predict ratings for unrated items? Please explain in simple terms.
Item
1 260 0.577305 780 0.5655413 1210 0.5529503 3114 0.5425038 1270 .....
2 367 0.5202925 364 0.5093084 500 0.5082204 586 0.4978301 480 ......
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