R help - Feb 2005 - Newbie: How to produce lm results at sub-level within df

Hi,

Given a data frame:

df1:  application id (appid), project id (pid), person
months (pm), function points (fp)

How do I produce linear modelling results at the appid
level.  That is, I would like to find the coefficent
and intercept for the formula "pm ~ fp" for each
application.

Thanks

?by

by(df1, df1$appid, function(x) summary(lm(pm ~ fp, data=x)))

Peter Rooney wrote:
> Hi,
> 
> Given a data frame:
> 
> df1:  application id (appid), project id (pid), person
> months (pm), function points (fp)
> 
> How do I produce linear modelling results at the appid
> level.  That is, I would like to find the coefficent
> and intercept for the formula "pm ~ fp" for each
> application.
-- 
Chuck Cleland, Ph.D.
NDRI, Inc.
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