levelsof Macro Limit: How to Extend?

[Attaullah Shah]

I am trying to feed a list of 40000 unique ids to the levelsof macro, my code and returned message are as follows:

levelsof gvkey, local(gv)
macro length exceeded

Is there any other way to transer the id list to a macro. Actually I want to estimate the following function

bys loc industry fyear: egen SDm=sd(DPO) if gvkey!=`gv'
where gv is the name of the local macro

[Clyde Schechter]

Can you explain better what you are trying to do? If your -levelsof- statement had succeeded, the local macro gv would have contained a very long list of values (be they numbers or strings, I don't know). And your subsequent -if gvkey != `gv'- would have thrown a syntax error because you can't just have a long list of things on the right side of an inequality: you must have an evaluable expression.

So if you can tell us what you were trying to accomplish, maybe we can figure it all out.

[Attaullah Shah]

Thanks Clyde for your reply. Please refer to this post http://www.statalist.org/forums/foru...ing-focal-firm
I am struggling with calculating standard deviation by year, industry and country, excluding the focal firm (i.e, excluding each firm in front of which the sd is calculated). Though I developed the following code for this purpose which works, but takes years to complete

set more off
levelsof loc, local(country)
foreach c of local country{
levelsof industry if loc=="`c'", local(ind) // loc is string that identifies each country
foreach i of local ind{
levelsof gvkey if industry==`i' & loc=="`c'", local(gk)
foreach g of local gk{
        forval y=1997/2009{
        quietly summarize ROA if gvkey!= `g' & fyear>`y'-1 & fyear<`y'+4 & loc=="`c'" & industry==`i'
        quietly replace SDx= r(sd) if gvkey==`g' & fyear==`y'+4
      }
}
}
}

[Nick Cox]

As the original author of levelsof, I am confident that there is a better approach for you if you are pushing at any associated limits.

See http://www.stata.com/support/faqs/da...ach/index.html Method 1 and come back to us with details if that doesn't appeal as a cleaner approach to your problem.