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Re: st: sigma u listed as zero despite unit variance
At 11:14 AM 2/24/2004, Amber E. Boydstun wrote:
The variability you're referring to is the margninal (unconditional)
variability of the outcome. It is small to begin with, and once you
condition on the variables you have in the model, there's essentially no
leftover variability for a random effect. That would be my guess.
Thanks for your help! You're right that when I run normal OLS I get the same
results (posted below). Can you tell me, is the reason that the random
estimator has degenerated into the OLS estimator that I have such a small
of variance of mean dependent variable values across my units (from
.6897267)? I guess I just thought that this small range would still count as
SOME amount of random error that would register as a very small sigma_u, but
something slightly greater than zero. Thanks again.
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