Clint Thompson wrote:
>I want to sort then keep every 5th observation, of a fictitious dataset. Aside from going into the data editor and manually deleting observations one-by-one (or using a series of drop/keep commands), is there a more elegant way to do this?? My initial idea was to generate a new variable using the
>_n system variable then keeping only those observations divisible by, say, five. Example:
>
>sort varname
>gen obsno = _n
>keep if (obsno/5)
Here's a quick example using the mod() function available in Stata:
. l
+----+
| y |
|----|
1. | 20 |
2. | 24 |
3. | 28 |
4. | 32 |
5. | 46 |
|----|
6. | 36 |
7. | 40 |
8. | 44 |
9. | 48 |
10. | 52 |
+----+
. keep if mod(_n,5) == 0
(8 observations deleted)
. l
+----+
| y |
|----|
1. | 46 |
2. | 52 |
+----+
--
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Eric G. Wruck
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