Um, I think not... The mean of the last 200 observation won't line up with the x and z.
Possibly, if what you want is the last 200 obs to have a different variance, y_obs <- y_model + c(rnorm(0.9 * n, 0, 0.1), rnorm(0.1 * n, 0, 0.5)) or y_obs <- rnorm(n, y_model, rep(c(0.1, 0.5), c(.9 * n, .1 * n))) -pd > On 17 Sep 2019, at 22:27 , David Winsemius <dwinsem...@comcast.net> wrote: > > > On 9/17/19 12:48 PM, varin sacha via R-help wrote: >> Dear R-helpers, >> >> Doing dput(x) and dput(y_obs), the 2 vectors are not the same length (1800 >> for y_obs and 2000 for x) >> How can I solve the problem ? >> >> Here is the reproducible R code >> >> # # # # # # # # # # >> library(mgcv) >> library(earth) >> >> n<-2000 >> x<-runif(n, 0, 5) >> y_model<- 0.1*x^3 - 0.5 * x^2 - x + 10 >> # y_obs<-rnorm(n*0.9, y_model, 0.1)+rnorm(n*0.1, y_model, 0.5) # maybe not >> exactly your goal? > > > You didn't lay out any goals for analysis, so let me guess what was intended: > > > I suspect that you were hoping to model a mixture composed of 90% from one > distribution and 10% from another. If I'm right about that guess then you > would instead wat to join the samples from each distribution: > > y_obs<-c( rnorm(n*0.9, y_model, 0.1), rnorm(n*0.1, y_model, 0.5) ) > > -- > > David > > >> gam_model<- gam(y_obs~s(x)) >> mars_model<- earth(y_obs~x) >> MSE_GAM<-mean((gam_model$fitted.values - y_model)^2) >> MSE_MARS<-mean((mars_model$fitted.values - y_model)^2) >> MSE_GAM >> MSE_MARS >> # # # # # # # # # # # # # # # # >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> 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. > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.