Hi, I can not comprehend the linear fitting results of polynoms. For example, given the following data (representing y = x^2):
> x <- 1:3 > y <- c(1, 4, 9) performing a linear fit > f <- lm(y ~ poly(x, 2)) gives weird coefficients: > coefficients(f) (Intercept) poly(x, 2)1 poly(x, 2)2 4.6666667 5.6568542 0.8164966 However the fitted() result makes sense: > fitted(f) 1 2 3 1 4 9 This is very confusing. How should one understand the result of coefficients()? Thanks for any tips, Firas. -- Firas Swidan, PhD Founder and CEO Olymons: Blessing Machines with Vision (TM) http://www.olymons.com P.O.Box 8125 Nazareth 16480 Israel Cell: +.972.(0)54.733.1788 ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
