Re: [R] help on retrieving output from by( ) for regression

From: Marc Schwartz <MSchwartz_at_mn.rr.com>
Date: Thu 25 Aug 2005 - 23:44:13 EST

Also, looking at the last example in ?by would be helpful:

attach(warpbreaks)
tmp <- by(warpbreaks, tension, function(x) lm(breaks ~ wool, data = x))

# To get coefficients:
sapply(tmp, coef)

# To get residuals:
sapply(tmp, resid)

# To get the model matrix:
sapply(tmp, model.matrix)

To get the summary() output, I suspect that using:

  lapply(tmp, summary)

would yield more familiar output as compared to using:

  sapply(tmp, summary)

The output from the latter might require a bit more "navigation" through the resultant matrix, depending upon how the output is to be ultimately used.

HTH, Marc Schwartz

On Thu, 2005-08-25 at 14:57 +0200, TEMPL Matthias wrote:
> Look more carefully at
> ?lm
> at the See Also section ...
>
> X <- rnorm(30)
> Y <- rnorm(30)
> lm(Y~X)
> summary(lm(Y~X))
>
> Best,
> Matthias
>
>
> > Hi all
> >
> > I used a function
> > > qtrregr <- by(AB, AB$qtr, function(AB) lm(AB$X~AB$Y))
> >
> > objective is to run a regression on quartery subsets in the
> > data set AB, having variables X and Y, grouped by variable qtr.
> >
> > Now i retrieved the output using qtrregr, however it only
> > showed the coefficients (intercept and B) with out
> > significant levels and residuals for each qtr. Can some on
> > help me on how can retrieve the detailed regression output.
> >
> > rgds
> >
> > snvk
> >



R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Thu Aug 25 23:49:05 2005

This archive was generated by hypermail 2.1.8 : Fri 03 Mar 2006 - 03:39:56 EST