Re: st: how do i increment a counter

[Christian Holz <statalist@krueschan.de>]

aine dooley wrote:
> I'm sure there is a more elegant way to do this, however ...
>

indeed, there is. Any a much easier and faster (both typing and 
computing time) way!

egen age1_sum=sum(exposure_time) if age<=50
egen age2_sum=sum(exposure_time) if age>50 & age <=75
egen age3_sum=sum(exposure_time) if age>75 & age <=90
egen age4_sum=sum(exposure_time) if age>90 & !mi(age)

creates a new variable for every "age group" which contains the 
cummulative exposure_time of that group if the patient belongs to that 
group and is missing otherwise, whereas

recode age (min/50=1) (51/75=2) (76/90=3) (90/max=4), gen (age_c)
bysort age_c: egen age_sum=sum(exposure_time)

creates one variable age_sum that contains the cummulative exposure_time 
of each patient's age group. (it works on the assumption that your age 
variable is integer)

Best from Scotland,
Christian

---
Christian Holz
Department of Sociology
University of Glasgow
Scotland, U.K.
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