Re: st: suppressing low frequency observations in tabulation

[Nick Cox <njcoxstata@gmail.com>]

This problem is addressed by the user-written program -modes-
originally published in STB-50 in 1999:

STB-50  sg113 . . . . . . . . . . . . . . . . . . . . . .  Tabulation of modes
        (help modes if installed) . . . . . . . . . . . . . . . . .  N. J. Cox
        7/99    pp.26--27; STB Reprints Vol 9, pp.180--181
        provides table of most frequent observations (modes)

The software was updated in Stata Journal 3(2) (2003) and 9(4) (2009)
so that the most recent version can be installed after typing

. net describe sg113_2, from(http://www.stata-journal.com/software/sj9-4)

Nick

On Wed, Oct 24, 2012 at 11:08 PM, Kevin McConeghy
<kevinmcconeghy@gmail.com> wrote:

> I have a large dataset, roughly 6.5mill obs, which is the FDA adverse
> event database. Variable drugname is the string describing the drug.
>
> . describe drugname
>
>               storage  display     value
> variable name   type   format      label      variable label
> ---------------------------------------------------------------------------------------------------------------------------------------------------
> drugname        str30  %30s
>
> I want to create a frequency table of the top 25 drug "offenders" in
> the database, however I am having trouble figuring out how to get
> Stata to perform the tab drugname command without including all the
> low frequency observations from random drugs (which causes stata to
> stop the command becuase "too many values"). I can't see an option for
> this in the syntax. Any advice on how to filter out all the background
> noise for this?
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