Carli,
Your estimated rho, -.999, with a standard error of .39 but a CI of -1 to 1
is telling you that your data are not informative enough to identify the
cross-equation correlation.
I highly recommend tracking down Butler's "Estimating the Correlation in
Censored Probit Models," The Review of Economics and Statistics, Vol. 78,
No. 2 (May, 1996), pp. 356-358, which has some suggested actions in such
cases.
Eric Lawrence
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