I have two very large independent groups (n=30,000 and 12,000). Each data point is an individual’s UK Deprivation Index decile (the Deprivation Index itself is a ranking from 1 to 32,844 of an area’s relative deprivation where 1 is most deprived). My hypothesis is that one group is more deprived than the other, i.e. has more people in the lower deciles.
The distributions look like this:
What would be the appropriate test for my hypothesis? Mann-Whitney?