st: Equivalence of Heckprob and ml model commands--initial values of rho

[Rachel <academicgirl@gmail.com>]

Suppose the initial values displayed in the 0th iteration of heckprob
are b1.....bn, atrho.


Now suppose I try to replicate the heckprob command using the same two
equations:

ml model (`maindv'=`depvars1') (`seldv'=`depvars2')  /athrho, trace
max gradient init(b1.....bn, atrho).

In the 0th iteration of this command, all the initial values of the
coefficients match those given in the init command EXCEPT for atrho.
(Note again that I passed the program atanh(rho), the initial value
calculated by heckprob and displayed as the initial value)

Can someone tell me what is going wrong?

Thanks again,
Rachel
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