st: comparing means of industry groups

["Fabian Schönenberger" <sch.f@gmx.ch>]

Dear Statalist

I am working with panel data; id=company, different variables for each company, and a time indicator t. Each company is assigned to an industry group (sic12); there are eleven different industries. 

I try to compare the means of one var for the different industries. I am interest in finding out if the means are statistically different among the industries. 

Are there any suggestions how to proceed with this analysis? 

My first approach was something like:

ttest var if inlist(sic12,1,2),by(sic12)

For each number of 1 to 12 (eleven is missing) the numbers in inlist(sic12,1,2) should vary:

ttest var if inlist(sic12,1,3),by(sic12)
ttest var if inlist(sic12,1,4),by(sic12)
...
ttest var if inlist(sic12,1,12),by(sic12)
ttest var if inlist(sic12,2,3),by(sic12)

I have no idea how to program this. 

Suggestions highly appreciated.

Many thanks

FS


 


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