 all rectangle ${\mathcal{C}}$, ${\boldsymbol{\theta}}, {\boldsymbol{\theta}}' \in {\mathcal{C}}$, the numbers $\bar{r}_{{\mathcal{C}},j}  ({\boldsymbol{\theta}},{\boldsymbol{\theta}}')$, $\underline{{r}}_{{\mathcal{C}},j}  ({\boldsymbol{\theta}},{\boldsymbol{\theta}}')$ are larger than $$\begin{aligned}  \label{eqSurretR