Displaying 2 results from an estimated 2 matches for "j3zmgrklihe73p4p".
2009 Apr 11
0
question related to fitting overdispersion count data using lmer quasipoisson
...k
into exp(....+rnorm()).
Then I fit a lmer quasipoisson model.
The estimation results are very off (see model output of fit.lmer.over.quasi
below).
Can someone kindly explain to me what went wrong?
Many thanks in advance.
-Sean
#data simulation (modified from code at
http://markmail.org/message/j3zmgrklihe73p4p)
set.seed(100)
m <- 5
n <- 100
N <- n*m
#X <- cbind(1,runif(N))
X <- cbind(1,rnorm(N))
X <- cbind(runif(N),rnorm(N))
id <- rep(1:n,each=m)
#
Z <- kronecker(diag(n),rep(1,m))
#Possion with group level heterogeneity
z <- rpois(N, exp(X%*%matrix(c(1,2)) + Z%*%matrix(rnorm(n)...
2009 Apr 11
0
Sean / Re: question related to fitting overdispersion count data using lmer quasipoisson
...k
into exp(....+rnorm()).
Then I fit a lmer quasipoisson model.
The estimation results are very off (see model output of fit.lmer.over.quasi
below).
Can someone kindly explain to me what went wrong?
Many thanks in advance.
-Sean
#data simulation (modified from code at
http://markmail.org/message/j3zmgrklihe73p4p)
set.seed(100)
m <- 5
n <- 100
N <- n*m
#X <- cbind(1,runif(N))
X <- cbind(1,rnorm(N))
X <- cbind(runif(N),rnorm(N))
id <- rep(1:n,each=m)
#
Z <- kronecker(diag(n),rep(1,m))
#Possion with group level heterogeneity
z <- rpois(N, exp(X%*%matrix(c(1,2)) + Z%*%matrix(rnorm(n)...