Side scattering and forward scattering of U937 cells. a) Experimental data. Side scattering is plotted against forward scattering. b) Result of cluster analysis by using the K-median clustering and spectral clustering with assuming 2 centers. c) Result of the cluster analysis by using the Misty Mountain method. Table 2 lists the characteristics of the resulting clusters. The data points assigned to the two clusters are marked by red and blue symbols.