Thanks to the help I have received from Uwe and Dimitris I have been
able to simulate the data as a list rather than separate objects and
structure in the long format. For the most part, all of my code is
working properly. There is one issue that I can't resolve.

When I do the following all seems to work as expected

lapply(long, function(x) summary(x$score.1)) #This works

Or
lapply(long, function(x) lm(x$score.1~x$time) #This works

But, when I replace the lm() with gls() I receive the following error

gltest<-lapply(long, function(x) gls(x$score.1~x$time,
correlation=corAR1(form=~1|x$V1), method='ML'))

Error in eval(expr, envir, enclos) : Object "V1" not found

If I remove the correlation argument altogether I then get an error that
score.1 is not found. Why is it that my variables are "found"  in other
situations but not for the gls call?

Thank you,

Harold

	[[alternative HTML version deleted]]


