I have a cell-plot chart (showing the means and standard deviations) of 9 domestic activities across a sample of 17 dwellings all belonging to one group (the same group).

The type of data is ordinal (ranking values). The purpose of this representation is to compare the relative ranking of 9 activities in relation to each other across the entire sample of 17 dwellings.

Request:

Kindly advise me on a non-parametric statistical test in order to compare the cell plots of just two (any two) of these activities against each other to find out whether there is a significant difference between them in terms of their ranking values (based on their means and standard deviations). My null hypothesis would be that there is no difference between the two compared activities.

Thank you for your time,

Mostafa.