Table 4.

Comparison of various clustering methods based on histogram summary measures. The numbers represent the average difference in cluster-wise mean and median survival times (in months) for each modality obtained using k-means clustering. Numbers in parentheses represent standard deviation of the differences based on 100 different initializations of the clustering algorithm.

		T1-weighted post contrast	T2-weighted FLAIR
Difference	Difference
Skew., Kurt., Range, Mode (Baek et al., 2012)	Mean	0.08 (0)	1.01 (0.55)
Median	0.05 (0)	1.81 (0.04)
5th and 95th percentile (Song et al., 2013)	Mean	6.85 (0.55)	2.64 (2.30)
Median	6.92 (0.26)	1.38 (1.05)
25th and 75th percentile (Just, 2011)	Mean	4.94 (≈ 0)	2.96 (1.03)
Median	5.10 (≈ 0)	2.36 (0.88)