right. How does it come that if I devide the result vector with 10*interception, I get a much better result?
> zz2 <- 25.86 -2239.86*mp$xx -595.01*mp$xx*mp$xx + 2875.54*mp$yy + > 776.84*mp$yy*mp$yy > mp$zz2 <- zz2 > library(lattice) > cloud(zz2/258.6 + zz ~ xx * yy, data=mp) looks quite pretty. http://r.789695.n4.nabble.com/file/n2322812/output.jpeg -- View this message in context: http://r.789695.n4.nabble.com/non-linear-regression-for-3D-data-tp2320982p2322812.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.