How can ordinary polynomial coefficients be calculated
from an orthogonal polynomial fit?
I'm trying to do something like find a,b,c,d from
lm(billions ~ a+b*decade+c*decade^2+d*decade^3)
but that gives: Error in eval(expr, envir, enclos) :
Object a not found
decade - c(1950, 1960, 1970,
On Tue, 14 Jun 2005, James Salsman wrote:
How can ordinary polynomial coefficients be calculated
from an orthogonal polynomial fit?
Why would you want to do that? predict() is perfectly happy with an
orthogonal polynomial fit and the `ordinary polynomial coefficients' are
rather badly
Prof Brian Ripley wrote:
On Tue, 14 Jun 2005, James Salsman wrote:
How can ordinary polynomial coefficients be calculated
from an orthogonal polynomial fit?
Why would you want to do that? predict() is perfectly happy with an
orthogonal polynomial fit and the `ordinary polynomial
I think this is covered in the FAQ:
http://cran.r-project.org/doc/FAQ/R-FAQ.html#Models
-roger
James Salsman wrote:
How can ordinary polynomial coefficients be calculated
from an orthogonal polynomial fit?
I'm trying to do something like find a,b,c,d from
lm(billions ~
On Tue, 14 Jun 2005, Frank E Harrell Jr wrote:
Prof Brian Ripley wrote:
On Tue, 14 Jun 2005, James Salsman wrote:
How can ordinary polynomial coefficients be calculated
from an orthogonal polynomial fit?
Why would you want to do that? predict() is perfectly happy with an
orthogonal
Prof Brian Ripley wrote:
On Tue, 14 Jun 2005, Frank E Harrell Jr wrote:
Prof Brian Ripley wrote:
On Tue, 14 Jun 2005, James Salsman wrote:
How can ordinary polynomial coefficients be calculated
from an orthogonal polynomial fit?
Why would you want to do that? predict() is perfectly