search for: timept

I'm trying to get code along the following lines to work: temp.name <- paste(TimePt,'df',sep='.') # invent a relevant name/symbol as a character string. assign(temp.name,IGF.df[IGF.df$TPt==TimePt,]) # this works. The relevant variable is now a data frame lm(b ~ Strain+BWt+PWt+PanPix, data=temp.name)) # this gives an error, namely Error in eval(predvars, data, env)...

Hi Is there any way to fit a bivaraite longitudinal mixed model using R. I have a data set with col names resp1 (Y_ij1), resp2 (Y_ij2), timepts (t_ij), unit(i) j=1,2,..,m and i=1,2,..n. I want to fit the following two models Model 1 Y_ij1, Y_ij2 | U_i = u_i ~ N(alpha + u_i + beta1*t_ij, Sigma) U_i ~ iid N(0, sigu^2) Sigma = bivariate AR structure alpha and beta are vectors of order 2. Model 2 Y_ij, Y_ij2 | U_i = u_i ~ N(alpha...

...> Hadley, hoping that a solution can be found using the original dataset. > > ######### My code > > # Creating dataset > > nPts<-10 # number of time points > nInd<-6 # number of individuals > nModel<-3 # number of models > > TimePts<-rep(1:nPts,nInd*nModel) # > creates the "Time" column > Coef<-rep(rnorm(6,0.1,0.01),each=nPts,nModel) # Creates a > vector of coefficients for generating the observations > Obs<-10*exp(-Coef*TimePts)...

...uot; <David.Epstein at warwick.ac.uk> To: r-help at r-project.org Subject: [R] puzzles with assign() Message-ID: <1273052867103-2130691.post at n4.nabble.com> Content-Type: text/plain; charset=us-ascii I'm trying to get code along the following lines to work: temp.name <- paste(TimePt,'df',sep='.') # invent a relevant name/symbol as a character string. assign(temp.name,IGF.df[IGF.df$TPt==TimePt,]) # this works. The relevant variable is now a data frame lm(b ~ Strain+BWt+PWt+PanPix, data=temp.name)) # this gives an error, namely Error in eval(predvars, data, env)...