Figure 1.

A graphical illustration of the main idea of DDR. There are multiple information sources that we can utilize to construct drug/disease similarities, and the constructed drug/disease similarity matrices are denoted by ${\left\{D_k\right\}}_{k=1}^{K_d}\text{or}{(S_l)}_{l=1}^{K_s}$. There is also an observed drug-disease association matrix R. Then DDR can learn the drug/disease grouping matrix U or V, the estimated drug-disease association matrix Θ and the importance of different drug/disease information sources ω or π.