[R] fitted values are different from manually calculating

[Douglas Bates]

On Feb 19, 2008 8:41 AM,  <gatemaze at gmail.com> wrote

> on a simple linear model the values produced from the fitted(model) function
> are difference from manually calculating on calc. Will anyone have a clue...
> or any insights on how fitted function calculates the values? Thank you.

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As the posting guide (you did read the posting guide, didn't you?)
says, it helps if you can provide a reproducible example.   Otherwise,
we can only guess at what you mean.

Try taking a fitted model and examining

model.matrix(model)

and

coef(model)

It should be the case that

model.matrix(model) %*% coef(model)

is reasonably close to fitted(model).

I just saw that Dimitris wrote almost the same thing but, since I have
written it, I'll mail it anyway.