How to delete the observations acording to percent generated by tabulate command

[Qiguo Lian]

Hi all，I want to delete the observations if the Percent of rep78 <40.00，any tips?

Similarly, I also want to know hpw to delete the observations if the Freq. of rep78 <30.

. sysuse auto, clear

(1978 Automobile Data)

. tab rep78

Repair
Record 1978	Freq.	Percent	Cum.
1	2	2.90	2.90
2	8	11.59	14.49
3	30	43.48	57.97
4	18	26.09	84.06
5	11	15.94	100.00
Total	69	100.00

[Nick Cox]

This should help. Note that the existence of missings should be considered one way or another.

. sysuse auto, clear
(1978 Automobile Data)

. bysort rep78 : gen count = _N

. count if rep78 < .
  69

. gen percent = 100 * count / r(N)

. tabdisp rep78, c(count percent)

----------------------------------
Repair    |
Record    |
1978      |      count     percent
----------+-----------------------
        1 |          2    2.898551
        2 |          8     11.5942
        3 |         30    43.47826
        4 |         18    26.08696
        5 |         11    15.94203
        . |          5    7.246377
----------------------------------

Notice that you can do things like this

bysort rep78 : drop if _N < 30

Again, watch out for missings.

[Qiguo Lian]

This should help. Note that the existence of missings should be considered one way or another.

. sysuse auto, clear
(1978 Automobile Data)

. bysort rep78 : gen count = _N

. count if rep78 < .
69

. gen percent = 100 * count / r(N)

. tabdisp rep78, c(count percent)

----------------------------------
Repair |
Record |
1978 | count percent
----------+-----------------------
1 | 2 2.898551
2 | 8 11.5942
3 | 30 43.47826
4 | 18 26.08696
5 | 11 15.94203
. | 5 7.246377
----------------------------------

Notice that you can do things like this

bysort rep78 : drop if _N < 30

Again, watch out for missings.

Thanks, Nick.