Return *OVLnl*

The ordinal variable V6 of the criterion *l* (Table 1) is calculated as the average of the *OVLnl* aggregated through the total amount of respondents:

$$\mathbf{x}\_{6l} = \frac{\sum\_{n=1}^{N} OVL\_{nl}}{N\_l} \,\mathrm{},\tag{12}$$

here *N<sup>l</sup>* is the amount of the non-zero values *rnl* for the criterion *l*.

The final set of the predefined variables and their optimums for the MCDM process is presented in Table 1.
