Given an OTS of length \(T\) with range \(\mathcal{S}=\{s_0, s_1, s_2, \ldots, s_n\}\) (\(s_0 < s_1 < s_2 < \ldots < s_n\)),
\(\overline{X}_t=\{\overline{X}_1,\ldots, \overline{X}_T\}\), the function computes the
matrix \(\widehat{\boldsymbol F}^c(l) = \big(\widehat{f}^c_{i-1j-1}(l)\big)_{1 \le i, j \le n}\),
with \(\widehat{f}^c_{ij}(l)=\frac{TN_{ij}(l)}{(T-l)N_i}\), where
\(N_i\) is the number of elements less one or equal to \(s_i\) in the realization \(\overline{X}_t\) and \(N_{ij}(l)\) is the number
of pairs \((\overline{X}_t, \overline{X}_{t-l})\) in the realization \(\overline{X}_t\)
such that \(\overline{X}_t \le s_i\) and \(\overline{X}_{t-l} \le s_j\).