Fig. 2
From: Deciphering modular and dynamic behaviors of transcriptional networks
A two-stage matrix decomposition of a microarray data set X (N genes and M samples) is obtained by ModulePro. The NICA extracts nonlinear independent components (columns in 
) from X. At the PSMF stage, 
is approximated by the product of sparse matrix Y and low-rank Z. The values of all matrices are color coded by using a color heatmap, from dark green (minimum) to dark red (maximum). (Reproduced from (Li et al. 2007b))