Dynamic Group Recommendation Algorithm Based on Member Activity Level

Table 4

Experimental results of nDCG@10 in Netflix.

Algorithm	NMF + K-means			K-means			Randomly
	5	10	20	5	10	20	5	10	20
SVD_AVG	0.875	0.854	0.816	0.786	0.801	0.768	0.145	0.165	0.116
SVD_LM	0.892	0.887	0.856	0.820	0.798	0.786	0.224	0.215	0.185
SVD_MP	0.835	0.814	0.776	0.714	0.701	0.718	0.153	0.153	0.118
SVD_Act	0.864	0.858	0.874	0.804	0.793	0.782	0.173	0.151	0.158
timeSVD++_AVG	0.884	0.873	0.853	0.790	0.804	0.772	0.172	0.179	0.126
timeSVD++_LM	0.907	0.885	0.873	0.837	0.818	0.790	0.216	0.239	0.179
timeSVD++_MP	0.843	0.826	0.788	0.752	0.737	0.728	0.186	0.163	0.120
WBF [34]	0.897	0.890	0.862	0.857	0.827	0.816	0.179	0.202	0.169
MCS [24]	0.915	0.897	0.854	0.874	0.826	0.804	0.214	0.205	0.163
DMA	0.885	0.915	0.903	0.844	0.854	0.826	0.189	0.214	0.172