st: tobit: missing columns in regression output

["Derbyshire, James" <james.derbyshire@anglia.ac.uk>]

Dear all,

I have come across a strange problem when using tobit regression. I am doing two regressions which are exactly the same, except they use different dependent variables.

The first regression produces a complete regression output table as per normal. The second regression, however, produces a regression table with coefficients, but blanks (dots) for all the other columns, as well as for the Prob > chi2 statistical.

However, when I run this second regression as an OLS regression instead, it works fine.

I have no idea what the problem is. I wonder whether it is a problem with the degrees of freedom but then why would the first regression work but not the second (they are identical and the dependent variables are very similar).

Thanks for any ideas.

James
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