Sum weights of independent variables across models (AIC)

Message: 102
Date: Wed, 13 Jul 2011 18:01:14 -0500
From: Michael Just <mgjust at gmail.com>
To: r-help <r-help at r-project.org>
Subject: [R] Sum weights of independent variables across models (AIC)
Message-ID:
	<CAHdFeLNoQBAHYL=CJ3dB=jbCuLDPyCGk03dNcyPF2obvkcAD+Q at mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

Hello,
I'd like to sum the weights of each independent variable across linear
models that have been evaluated using AIC.

For example:

library(MuMIn)
data(Cement)
lm1  <-  lm(y  ~  .,  data  =  Cement)
dd  <-  dredge(lm1,  beta  = TRUE,  eval  =  TRUE,  rank  =  "AICc")
get.models(dd, subset = delta <4)

There are 5 models with a Delta AIC Score of less than 4.  I would
like to sum the weights for each of the independent variables across
the five models.