help in fitted values in lm function

If you want fitted() to return NAs in the positions where
there were NA's in data, use na.action=na.exclude in your
call to lm().  E.g.,

  > z <- data.frame(y=1:5, x=c(1,NA,3,3,5))
  > fitted(lm(y~x, data=z))
     1    3    4    5 
  1.25 3.25 3.25 5.25 
  > fitted(lm(y~x, data=z, na.action=na.exclude))
     1    2    3    4    5 
  1.25   NA 3.25 3.25 5.25

I think the help file for model.matrix has more detail,
including how to use options() to set the na.action for
your R session.

Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of arunkumar1111
Sent: Monday, November 14, 2011 3:36 AM
To: r-help at r-project.org
Subject: Re: [R] help in fitted values in lm function

Yes there are few NA in the Data

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