Displaying 3 results from an estimated 3 matches for "designmatrix".
2012 Dec 05
1
Using multcomp::glht() with Anova object
...dition, Region),
idesign=~Condition*Region ) )
I'm now trying to do post-hoc comparisons between all levels of Condition
using glht() from the multcomp package. I do this using the way that has
worked for me with lmer() objects in the past: set up a contrast matrix and
then feed it to glht():
designmatrix <- matrix(0, nrow=3, ncol=18)
rownames(designmatrix) <- c("Cond1_minus_Cond2", "Cond3_minus_Cond1",
"Cond3_minus_Cond2")
designmatrix[1, 1:6] <- 1
designmatrix[1, 7:12] <- -1
designmatrix[2, 1:6] <- -1
designmatrix[2, 13:18] <- 1
designmatrix[3, 13:18...
2006 Jul 20
1
Loss of numerical precision from conversion to list ?
...y(nlme)
data(Orthodont) #108 dental measurements on 27 subjects
# m1<-lme(distance~age,random=~1|Subject,data=Orthodont)
# summary(m1)
# ...
# Random effects:
# Formula: ~1 | Subject
# (Intercept) Residual
# StdDev: 2.114724 1.431592 -> lambda.REML=2.114^2/1.431^2 = 2.182382
#DesignMatrix for fixed Effects
X<-cbind(rep(1,108),Orthodont$age)
#DesignMatrix of RandomEffects
Z<-matrix(data=c(rep(1,4),rep(0,108)),nrow=108,ncol=27)
#Corr(RanEf)^0.5 = 27 x 27 Identity, since RandomIntercepts are independent
sqrt.Sigma<-diag(27)
K<-27 #number of subjects/ random intercepts...
2004 Jan 28
1
Large data sets and memory management in R.
Hello R-users,
First my settings: R-1.8.1, compiled as a 64bit application for a Solaris
5.8, 64 bit. The OS has 8Gb of RAM available and I am the sole user of the
machine, hence pretty much all the 8Gb are available to R.
I am pretty new to R and I am having a hard time to work with large data
sets, which make up over 90% of the anlyses done here. The data set I
imported in R, from S+, has a