# Re: st: cumulative average moving through time

 From smerryman@kc.rr.com To statalist@hsphsun2.harvard.edu Subject Re: st: cumulative average moving through time Date Wed, 06 Oct 2004 14:18:05 -0500

Dan,

Try

bysort pid (ob):gen cave = sum(calc)/ob

Hope this helps,
Scott

----- Original Message -----
From: Daniel Egan <dp.egan@gmail.com>
Date: Wednesday, October 6, 2004 1:38 pm
Subject: st: cumulative average moving through time

> Hello all,
>
> I have iregularly spaced time/measurement data. I want to
> calculate an
> average using all prior measurements. FYI, the variable to be
> "averaged" is a dummy, so I would be looking at a percentage.
>
> a hail mary was:
>
> sort PID OB
> egen calc_sum=sum(calc[_n-_n]), by(PID)
> gen cave=calc_sum/OB
>
> which obviously does not work.
>
> My data looks like this. cave is the variable i wish I knew how to
> create.
>
> PID	OB	dm	dm_m	calc	cave
> 1	1	1-4-2000	0	1	1
> 1	2	1-10-2000	6	0	.5
> 1	3	1-28-2000	24	0	.333
> 1	4	2-1-2000	28	1	.5
> 2	1	10-5-1998	0	1	1
> 2	2	10-8-1998	3	0	.5
> 2	3	1-22-1998	17	1	.666
> 2	4	11-5-1998	31	1	.75
>
>
>
> Thanks,
>
> Dan
>

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