Re: st: creating variables using 'by' for subsets of records

[Eric Booth <ebooth@ppri.tamu.edu>]

>

Something like this:

****************BEGIN EXAMPLE
/*
I have records for individuals by geographic region and wish to aggregate
the records for individuals to records for geographic regions.  I believe I
should create variables for those regions using 'by'. 
*/
clear

inp indiv str6 region indicator
1 "north" 6 
2 "north" . 
3 "north" .
4 "south" 5
5 "south" 5
6 "south" .
7 "east" 3 
8 "east" 9
9 "east" 0 
10 "east" 6
end

egen region_code = group(region)
*or use -encode-*

/*
...to create a region variable that expresses a ratio of
count of indicator values for individuals in a region to a count of
individuals in the region and am unsure how to code this.
*/

foreach v in indicator indiv {
	bys region: egen ind_`v' = count(`v')
	label var `v' "Count of `v'"
	}
*ratio*
g ratio = ind_indicator/ind_indiv
li ind* ratio
****************END EXAMPLE

~ Eric
__
Eric A. Booth
Public Policy Research Institute
Texas A&M University
ebooth@ppri.tamu.edu
Office: +979.845.6754


On Feb 23, 2010, at 1:55 PM, John Westbury wrote:

> I have records for individuals by geographic region and wish to aggregate
> the records for individuals to records for geographic regions.  I believe I
> should create variables for those regions using 'by'.  Ex: by Region gen x =
> argument for variable.  I am having difficulty with arguments for variable
> x.  For example I wish to create a region variable that expresses a ratio of
> count of indicator values for individuals in a region to a count of
> individuals in the region and am unsure how to code this.




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