文章目录案例–算法实现：Item-Based CF 预测评分算法实现
案例–算法实现：Item-Based CF 预测评分
评分预测公式：
pred(u,i)=r^ui=∑j∈Iratedsim(i,j)∗ruj∑j∈Iratedsim(i,j)
pred(u,i)=\hat{r}_{ui}=\cfrac{\sum_{j\in I_{rated}}sim(i,j)*r_{uj}}{\sum_{j\in I_{rated}}sim(i,j)}
pred(u,i)=r^ui=∑j∈Irated
