Use of lm on polynomial models (PR#14014)

Full_Name: Michael Aaron Karsh
Version: 2.8.0.
OS: Windows XP
Submission from: (NULL) (75.61.102.255)


When I try lm(w ~ h^3 + h^2 + h) for example, it only gives 
coefficients for the intercept and for h.  It does not give 
coefficients for h^2 or h^3.

RTFM time: h^3 is not the cube of h in an R formula (for that you need 
I(h^3)).  See ?formula, for example.

Simpler would be lm(w ~ poly(h, 3, raw=TRUE))


On Sun, 18 Oct 2009, michael_karsh at earthlink.net wrote:

Full_Name: Michael Aaron Karsh
Version: 2.8.0.
OS: Windows XP
Submission from: (NULL) (75.61.102.255)


When I try lm(w ~ h^3 + h^2 + h) for example, it only gives coefficients 
for the intercept and for h.  It does not give coefficients for h^2 or h^3.

So it is behaving correctly.


-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
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