# Re: st: How to use r(p)

 From Jean-Benoit Hardouin <[email protected]> To [email protected] Subject Re: st: How to use r(p) Date Mon, 12 Sep 2005 11:10:26 +0200

```. centile d, centile(33 66)
. reg y a b c if d<=r(c_1)
. reg y a b c if d>r(c_1)&d<r(c_2)
. reg y a b c if d>=r(c_2)

Jean-Benoit Hardouin

FUKUGAWA, N. a écrit :

```
Dear all,
What if we want to run 3 regression models according to the classification of variable "d"?

centile d, centile(33)
centile d, centile(66)
reg y a b c if d<=r(c_1)
reg y a b c if d>r(c_1)&d<r(c_2)
reg y a b c if d>=r(c_2)

--
[email protected]

Jean-Benoit Hardouin wrote:

```You can try
. centile d, centile(33)
. reg y a b c if d>r(c_1)
Best,
Jean-Benoit Hardouin

FUKUGAWA, N. a écrit :

```
Dear all,
Suppose we want to limit observations where one variable records a larger value
than its top quartile, we can write as follows.

sum d,detail
reg y a b c if d>r(p75)

However, this program allows only fixed thresholds such as 1, 10, and 75 percent.
How can I use other thresholds such as r(p33) in the program?
Or, is there any program to do the same?

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```
```--
*********************************************
Jean-Benoit Hardouin
Biostatisticien
Observatoire Régional de la Santé du Centre
BP 2439
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Email : [email protected]
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```