search for: tolerance1_pp

...I can't add the spline, a overall trend line. In the SAS code they use the command 'I=SM50S' and I would prefer something similar. I?m using R 2.10.1 on windows XP? I have made this working example. tolerance.pp <- read.table("http://www.ats.ucla.edu/stat/R/examples/alda/tolerance1_pp.txt ", sep=",", header=T) # install.packages("lattice", dep = T) library(lattice) xyplot(tolerance ~ age, groups = id, data=tolerance.pp, type = "l") This is where I want to add a overall spline. Hope someone out there can figure this out. Thanks Eric

...but not with the other plots, from the NPK dataset: # from http://www.ats.ucla.edu/stat/r/examples/alda/ch2.htm tolerance <- read.csv("http://www.ats.ucla.edu/stat/r/examples/alda/data/tolerance1.txt") tolerance.pp <- read.csv("http://www.ats.ucla.edu/stat/r/examples/alda/data/tolerance1_pp.txt") attach(tolerance.pp) # fitting the linear model by id fit <- by(tolerance.pp, id, function(bydata) fitted.values(lm(tolerance ~ time, data=bydata))) fit <- unlist(fit) # plotting the linear fit by id interaction.plot(age, id, fit, xlab="age", ylab="tolerance")...