Some examples (assumes installation of -groups- and -modes-):
. sysuse auto
(1978 Automobile Data)
. groups mpg, order(h) select(5)
+-------------------------------+
| mpg Freq. Percent Cum. |
|-------------------------------|
| 18 9 12.16 12.16 |
| 19 8 10.81 22.97 |
| 14 6 8.11 31.08 |
| 21 5 6.76 37.84 |
| 22 5 6.76 44.59 |
+-------------------------------+
. groups mpg, order(h) select(f >= 3)
+-------------------------------+
| mpg Freq. Percent Cum. |
|-------------------------------|
| 18 9 12.16 12.16 |
| 19 8 10.81 22.97 |
| 14 6 8.11 31.08 |
| 21 5 6.76 37.84 |
| 22 5 6.76 44.59 |
|-------------------------------|
| 25 5 6.76 51.35 |
| 16 4 5.41 56.76 |
| 17 4 5.41 62.16 |
| 24 4 5.41 67.57 |
| 20 3 4.05 71.62 |
|-------------------------------|
| 23 3 4.05 75.68 |
| 26 3 4.05 79.73 |
| 28 3 4.05 83.78 |
+-------------------------------+
. modes mpg
Mode of mpg
----------------------
Mileage |
(mpg) | Frequency
----------+-----------
18 | 9
----------------------
. modes mpg, nmodes(5)
----------------------
Mileage |
(mpg) | Freq.
----------+-----------
14 | 6
18 | 9
19 | 8
21 | 5
22 | 5
25 | 5
----------------------
Nick
[email protected]
Nick Cox
-fre- is excellent for this and related problems.
But there are other solutions too which have been around for some time.
-modes- from SJ does what Rodrigo wants. So would -groups- from SSC.
-groups- has one advantage over -modes- or -fre-: it extends to frequencies of two or more variables considered jointly.
Nick
[email protected]
Martin Weiss
One could think of constructs with the -in- qualifier here, but Maarten`s answer is unbeatable: -ssc d fre- takes care of both ordering and subsetting the values...
Rodrigo Briceño
> Thanks Maarten and Martin. To clarify my opaque need to Martin what I
> need is that the table produced only shows the first ten values (the
> highest 10 values or any other small figure) to avoid having really
> long tables of results and further editing (erasing anything below the
> 10th greatest value). It is more clear now?
>
> 2009/3/18 Maarten buis <[email protected]>:
> >
> > --- Rodrigo Briceno wrote:
> >> I recently discovered the use of the command
> >> tab with the option sort in order to get an ordered table of
> >> frequencies (descendant order).
> >> I am wondering if I can use an additional option in order to show only
> >> some specific set of results, since some categories on my tables are
> >> really long (more than 256 categories in one case).
> >> Also I have the doubt if tab could be combined with an option in order
> >> to get ascendant frequencies.
> >
> > Yes, see -ssc describe fre- for Ben Jann's -fre- package.
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
