st: RE: combining frequency tables

 From "Nick Cox" To Subject st: RE: combining frequency tables Date Mon, 23 Feb 2009 16:01:48 -0000

```As I've said before, there's no virtue in simple questions. We want
_interesting_ questions!

This seems to be a question about Excel to the extent that it raises
another question: Can't you do that in Excel if that's a tool of choice?
(No idea from me.)

But there are also many Stata answers. -findit mdesc- reveals that it is
a program by Rose Anne Medeiros, who once wrote a program called -njc-,
for which I am not responsible. Here is a matrix version of her program,
for which she is not responsible.

*! mmdesc 1.0 NJC 23 February 2009
* mdesc 1.0 RAM 18 JULY 2008
* Returns a table with number missing, total, and missing/total
program mmdesc, rclass byable(recall)
version 8
syntax [varlist] [if] [in]
tempvar touse
mark `touse' `if' `in'
local nvars : word count `varlist'
tempname matrix
matrix `matrix' = J(`nvars', 3, .)
local i = 1
quietly foreach var of local varlist {
count if missing(`var') & `touse'
matrix `matrix'[`i', 1] = r(N)
count if `touse'
matrix `matrix'[`i', 2] = r(N)
matrix `matrix'[`i', 3] = `matrix'[`i',1] / `matrix'[`i',2]
local ++i
}
matrix rownames `matrix' = `varlist'
matrix colnames `matrix' = Missing Total Missing/Total
return matrix table = `matrix'
end

Once you run this, you can save its results by e.g.

mat A = r(table)

...

mat B = r(table)

...

mat C = A + B

Nick
n.j.cox@durham.ac.uk

Another (perhaps) simple question: is it possible to add different
frequency tables together to form a combined single table in Excel?

I have two group variables (say, var1: type of treatment; and var2: time

point of observation) and 5 use variables. So an observation would be
for
treatment A at time point 1. I want to know the number of missing values

for each use variable for each treatment group and each time point. Also

for each use variable there are 'if' conditions, so I can't do the
frequency count in one go. Here is what I am doing using a user written
programme -mdesc- or -missing-:

by treatment timpoint: mdesc use1 if (condition1 condition2)

by treatment timpoint: mdesc use2 if (condition3 condition4)

and so on.

Now I want to combine all these counts for all timepoints and treatment
groups to get a single table that I can export to Excel. Is there any
way I
could do that?

*
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```