Visualizing the matrix, equation 3.6 for St-RKM models after training on three data sets. The first two rows show, equation 3.6, where $U=U★∈St(ℓ,m)$ is the output of algorithm 1. These matrices are effectively close to being diagonal and especially for $St-RKM-sl$⁠, as expected. In contrast, the third row shows the same matrix, equation 3.6, with $U∈St(ℓ,m)$ sampled uniformly at random (see Table 6 for the corresponding normalized diagonalization errors).