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Re: st: RE: RE: joinby command and memory issues
From
"Weichle, Thomas" <[email protected]>
To
<[email protected]>
Subject
Re: st: RE: RE: joinby command and memory issues
Date
Tue, 12 Oct 2010 12:02:48 -0500
Eric, I'm trying to apply the second method that you suggested because I
need to keep all the receipt dates. After I reshape epo.dta, it creates
a dataset of 1 record per individual. Here are my reshaped data
results. 36,381 individuals with a maximum of 854 dates. Someone
received the EPO drug very often! Now that I have 1 record per
individual, wouldn't it be appropriate to then do a 1:m (many) merge
instead of a joinby where the many represents each of the hemoglobin
test dates for the individual? I believe the data are set up
appropriately for this 1:many merge.
reshape wide epo_dt, i(study_id) j(i)
Data long -> wide
------------------------------------------------------------------------
-----
Number of obs. 278492 -> 36381
Number of variables 4 -> 856
j variable (854 values) i -> (dropped)
xij variables:
epo_dt -> epo_dt1 epo_dt2 ...
epo_dt854
------------------------------------------------------------------------
-----
Tom Weichle
Math Statistician
Center for Management of Complex Chronic Care (CMC3)
Hines VA Hospital, Bldg 1, C202
708-202-8387 ext. 24261
[email protected]
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