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Re: st: Dropping variables with mostly missing values again
From
Nick Cox <[email protected]>
To
"[email protected]" <[email protected]>
Subject
Re: st: Dropping variables with mostly missing values again
Date
Sat, 8 Feb 2014 09:27:13 +0000
Not the way to do it. It's just
npresent, min(20)
keep `r(varlist)'
Example:
. sysuse auto
(1978 Automobile Data)
. gen useless = .
(74 missing values generated)
. gen justasuseless = ""
(74 missing values generated)
. npresent, min(20)
make 74
price 74
mpg 74
rep78 69
headroom 74
trunk 74
weight 74
length 74
turn 74
displacement 74
gear_ratio 74
foreign 74
. keep `r(varlist)'
. ds
make mpg headroom weight turn gear_ratio
price rep78 trunk length displacement foreign
-useless- and -justasuseless- have gone.
Nick
[email protected]
On 8 February 2014 02:00, Eric M. Uslaner <[email protected]> wrote:
> Thanks to Rich, Amirsa, Jeph, and Nick. It is likely my ignorance but I can't get this resolved. For the solutions of Rich, Amirsa, and Jeph, I get all missing values. For Nick's suggestion, I have:
>
> foreach V of varlist elecprod1750-visitorrooms2003 {
> npresent,min(20)
> keep `r(`V')'
> }
>
> And I see the npresent results as he suggested. But the do file I constructed above after the last variable leads to:
>
> varlist or in range required
> r(100);
>
> end of do-file
>
> r(100);
>
> And no values are changed. What, please, am I doing wrong? Thanks.
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