Dynamic Group Recommendation Algorithm Based on Member Activity Level

Table 3

Experimental results of nDCG@10 in MovieLens.

Algorithm	NMF + K-means			K-means			Randomly
	5	10	20	5	10	20	5	10	20
SVD_AVG	0.897	0.878	0.859	0.801	0.807	0.791	0.153	0.176	0.159
SVD_LM	0.911	0.881	0.839	0.830	0.839	0.816	0.213	0.228	0.174
SVD_MP	0.883	0.823	0.771	0.811	0.785	0.738	0.164	0.157	0.102
SVD_Act	0.881	0.871	0.915	0.823	0.820	0.837	0.160	0.181	0.154
timeSVD++_AVG	0.9	0.891	0.868	0.826	0.831	0.806	0.172	0.236	0.201
timeSVD++_LM	0.915	0.893	0.863	0.843	0.853	0.840	0.196	0.244	0.183
timeSVD++_MP	0.896	0.854	0.779	0.836	0.815	0.768	0.192	0.167	0.125
WBF [34]	0.893	0.897	0.878	0.878	0.889	0.850	0.182	0.216	0.185
MCS [24]	0.901	0.884	0.867	0.885	0.876	0.853	0.209	0.215	0.158
DMA	0.892	0.906	0.929	0.851	0.877	0.875	0.197	0.228	0.176