[R] simulation

[Oarabile Molaodi]

I am trying to write a function that will simulate observed counts X and 
Y as below, I want the function to be able give many replicates, can 
somebody advise?
thanks
Oarabile

#alpha,n sdx and sdy  are constant, and N is a vector of length n.
unstructured<-function(n,N,alpha,sdx,sdy){
Vx<-rnorm(n,mean=0,sd=sdx)
Vy<-rnorm(n,mean=0,sd=sdy)
thetax<-exp(alpha+Vx)
thetay<-exp(alpha+Vy)
X<-rpois(n,N*thetax)
Y<-rpois(n,N*thetay)
data.frame(X,Y)
 }
set.seed()
unstructured()

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Mrs Oarabile Ruth Molaodi
Department of Statistics and Modelling Science
University of Strathclyde
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