Yu-Kang -
Simulations by their nature use randomly generated data.
Sometimes the random data doesn't contain enough information
to fully determine the parameter estimates for one iteration
or another. It seems likely that that is what happened here.
The design matrix is singular for one iteratio
Dear R-users,
I am a dentist (so forgive me if my question looks stupid) and came across
a problem when I did simulations to compare a few single level and two
level regressions.
The simulations were interrupted and an error message came out like 'Error
in MEestimate(lmeSt, grps) : Singularity
