Table 1. Data comparison before and after clustering of the four algorithms.

	Accuracy rate		Recall rate
	Before clustering		After clustering
ALS_User_CF	0.71	0.74	0.63	0.67
FunkSVD	0.61	0.66	0.51	0.53
SVD	0.60	0.63	0.49	0.51
CF	0.51	0.53	0.41	0.42