Understanding Society User Support

Dear all,

I am analysing the data in STATA using the svyset command where I need to use the strata variable you provide. However, I cannot run a logistic regression because I get this note:

''Note: Missing standard errors because of stratum with single sampling unit.
Note: 2 strata omitted because they contain no population members. ''

It seems that the strata variable has a maximum value of 3319 which indicates a lower level of geographical area and I was wondering if there is any other variable in the dataset that indicates the higher level of geographical area, i.e. a variable that narrows down the areas?

Also, in the dataset guideline in the 'psu' section you state that ' The list of all sectors was then sorted into twelve geographical strata, consisting of ten regions in England plus Scotland and Wales as separate strata.'. Is it possible to know which sub-strata belongs to each of the original twelve strata?

Thank you in advance.

Dora