Re: st: Selecting maximum values and generating sum variable

[Maarten Buis <maartenlbuis@gmail.com>]

On Tue, May 24, 2011 at 4:33 AM, Catherine Tisch wrote:
> 1.      We want to select the highest UVI value per ID per day from five
> hourly measurements.  It is possible for measurements to be zero and in
> some instances data is missing. <snip>
> 2.      We want to know the sum of count of days per ID if UVIPeak is
> not missing.

*------------------ begin example ---------------
clear
input ///
ID    Day    Hour         UVI
1     1      11           5
1     1      12           9
1     1      13           7
1     1      14           3
1     1      15           4
1     2      11           7
1     2      12           8
1     2      13           2
1     2      14           1
1     2      15           .
1     3      11           1
1     3      12           2
1     3      13           1
1     3      14           1
1     3      15           0
2     1      11           .
2     1      12           .
2     1      13           .
2     1      14           .
2     1      15           .
2     2      11           9
2     2      12           10
2     2      13           10
2     2      14           8
2     2      15           6
end

bys ID Day : egen UVIpeak = max(UVI)
list
bys ID Day : gen byte notmiss = !missing(UVIpeak) if _n == 1
bys ID : egen SumDays = total(notmis)
list
drop notmiss
list
*----------------------- end example -----------------------
(For more on examples I sent to the Statalist see:
http://www.maartenbuis.nl/example_faq )

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------

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