Coding by ranks
Transform your numerical data values into ranks if only their order is important. Do it in Excel using the XLSTAT add-on statistical software.
How to use coding by rank
This tool is used to recode a table with n observations and p quantitative variables into a table containing ranks, the ranks being determined variable by variable.
Coding in ranks lets you convert a table of continuous quantitative variables into discrete quantitative variables if only the order relationship is relevant and not the values themselves or if you want to neutralize the influence of outliers.
XLSTAT options for coding by ranks
Two strategies are possible for taking tied values into account: either they are assigned to the mean rank or they are assigned to the lowest rank of the tied values.