RE: st: tab most frequently occurring

["Nick Cox" <n.j.cox@durham.ac.uk>]

Thanks for the mention. -groups- is on SSC and was discussed in SJ 3-4. 

SJ-3-4  pr0011  . . . . . . . .  Speaking Stata: Problems with tables,
Part II
        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  N.
J. Cox
        Q4/03   SJ 3(4):420--439                                 (no
commands)
        reviews three user-written commands (tabcount, makematrix,
        and groups) as different approaches to tabulation problems

See also -modes-. 

SJ-9-4  sg113_2 . . . . . . . . . . . . . . . . . . . . .  Tabulation of
modes
        (help modes if installed) . . . . . . . . . . . . . . . . .  N.
J. Cox
        Q4/09   SJ 9(4):652
        update to allow the generate() option to record in an
        indicator variable of which observations contain values
        matching any of the modes displayed

SJ-3-2  sg113_1 . . . . . . . . . . . . . . . . . .  Software update for
modes
        (help modes if installed) . . . . . . . . . . . . . . . . .  N.
J. Cox
        Q2/03   SJ 3(2):211
        provides new option for specifying the number of modes to
        be shown

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)

However, to expand Scott's comment: Neither offers solutions to (b) or
(c). Maarten has given some code. A hybrid of his code and -modes- would
give you (b) and (c) as well. 

Nick 
n.j.cox@durham.ac.uk 

Scott Merryman

Nick Cox's -groups- can handle (a):

. sysuse auto, clear
(1978 Automobile Data)

. groups gear, select(5) order(h)

  +------------------------------------+
  | gear_r~o   Freq.   Percent    Cum. |
  |------------------------------------|
  |     2.73       9     12.16   12.16 |
  |     2.93       8     10.81   22.97 |
  |     3.08       7      9.46   32.43 |
  |     2.47       5      6.76   39.19 |
  |     2.41       3      4.05   43.24 |
  +------------------------------------+

. groups gear, select(freq>=3) order(h)

  +------------------------------------+
  | gear_r~o   Freq.   Percent    Cum. |
  |------------------------------------|
  |     2.73       9     12.16   12.16 |
  |     2.93       8     10.81   22.97 |
  |     3.08       7      9.46   32.43 |
  |     2.47       5      6.76   39.19 |
  |     2.41       3      4.05   43.24 |
  |------------------------------------|
  |     3.05       3      4.05   47.30 |
  |     3.54       3      4.05   51.35 |
  |     3.78       3      4.05   55.41 |
  +------------------------------------+

On Wed, Mar 17, 2010 at 8:30 AM, Richard Goldstein
<richgold@ix.netcom.com> wrote:
> I want to -tabulate- a variable with many (hundreds if not thousands
of)
> different values; but, I only want to see (a) the 20 (say) most
> frequently occurring values and then (b) I want a row for "all others"
> and then (c) I want a grand total row
>
> I have searched in various ways for already existing programs but, of
> course, I may have missed something (as far as I can see, -fre- will
not
> do what I want but I would be happy to be shown that I was wrong)
>
> so, two questions:
>
> does anyone know of an already existing program for this?
>
> hints, etc. for writing my own would be welcome also if anyone has any


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