Representational dissimilarity matrix
= Representational dissimilarity matrix
{title2=$D_{ij}=1-\operatorname{corr}(z_i,z_j)$}
= RDM
{c}
{synonym}
A <matrix> whose entry $D_{ij}$ describes how differently a system responds to stimuli $i$ and $j$. One convention is $D_{ij}=1-\operatorname{corr}(z_i,z_j)$ when the response <vectors> have nonzero variance. Such a dissimilarity need not satisfy every metric axiom. Model comparison must control fitted transformations and use held-out data.