Michael Just wrote:
Great,
Thanks,
Michael
On Mon, Oct 13, 2008 at 3:56 PM, Rolf Turner <[EMAIL PROTECTED]>wrote:
On 14/10/2008, at 9:42 AM, Michael Just wrote:
What is the difference when including or not including the intercept when
using lm()?
x.noint <- lm(weight ~ group - 1))# omitting intercept
x <- lm(weight ~ group))
This has nothing to do with forcing the intercept to 0, correct?
On the contrary. This is *exactly* what it means.
But if group is a factor, this removes the intercept _and_ uses the full
set of indicator variables to represent the factor, so you end up with
the same model, just parametrized differently.
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