 $$\begin{aligned} \underline{\boldsymbol{r}}_{{\mathcal{C}}} ({\boldsymbol{\theta}},{\boldsymbol{\theta}}')  &=&  \left(0 \sigma \sqrt{{ \kappa H^0 (f_{{\boldsymbol{\theta}}}, f_{{\boldsymbol{\theta}}'})}} ,  \sigma 