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[NMusers] unbalanced data set

From: Zheng Liu <>
Date: Wed, 6 Jan 2016 02:03:05 +0000

Dear all,

I recently have a data set for pk parameters fitting. The issue is some pat=
ients have far more measurement points than others (i.e. a few patients hav=
e ~15 points, other patients have only 1 or 2). I speculate in the fitted p=
arameters, those patients with many points would contribute much more than =
those with less points. Then the population "average" values of fitted pk p=
arameters are not anymore average from all the patients, but more biased to=
 those patients with many points. This is not what I expect.

Of course I could take away some points from the patients with many points,=
 in order to be comparable to less-points patients. Then I will be forced =
to lose some information from the data set. I just wonder are there anyone =
who have better proposal to solve this problem? I appreciate your help very=

Best regards,


Received on Tue Jan 05 2016 - 21:03:05 EST

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