Re: st: row means for at least 10 observations greater than 0

[Jeph Herrin <info@flyingbuttress.net>]

Or - in the interests of brevity - if you have say 25 variables

 	egen has0s   = anycount(var1990-var2014), val(0)
	egen rowmean = rowmean(var1990-var2014) if (25 - has0s) >=10


J




On 2/25/2014 10:37 AM, Nick Cox wrote:
> Let's count positives first. One simple way is a loop. I imagine
> variable names -var1990-var2013-. I throw in free a check for
> non0missing.
>
> gen positive = 0
>
> qui foreach v of var var1990-var2013 {
>        replace positive = positive + (`v' > 0 & `v' < .)
> }
>
> egen rowmean = rowmean(var1990-var2013) if positive >= 10.
>
> For technique here see
>
> SJ-9-1  pr0046  . . . . . . . . . . . . . . . . . . .  Speaking Stata: Rowwise
>          (help rowsort, rowranks if installed) . . . . . . . . . . .  N. J. Cox
>          Q1/09   SJ 9(1):137--157
>          shows how to exploit functions, egen functions, and Mata
>          for working rowwise; rowsort and rowranks are introduced
>
> http://www.stata-journal.com/sjpdf.html?articlenum=pr0046
>
> (If negative values are acceptable, modify the loop accordingly.)
>
> Nick
> njcoxstata@gmail.com
>
> On 25 February 2014 15:30, Nicholas Winters
> <nicholas.winters@mail.mcgill.ca> wrote:
> > I need to take an average of several variables in a row, but I want to average of the row only if there are at least 10 variables without 0 as their observation. The data looks like this:
> >
> > PersonID  1990 1991 1992 1993 1994 1995 etc...
> > 1               0       0       3      3      5       6
> > 2               1       1       5      3      0       7
> > 3               1       1       2      1      4       3
> > 4               0       0       0      0      5       5
> >
> > does anyone have an idea how to do this? I've tried egen and rowmean() but I am not sure how to code for if a row has more at least 10 observations > 0
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/faqs/resources/statalist-faq/
> *   http://www.ats.ucla.edu/stat/stata/
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/