st: error report with ml check

[健 张 <victerzj2@yahoo.com.cn>]

Hi, all:
I am trying to write my own code to do the maximize likelihood 
estimation of bivariate probit model. I know I can use the biprobit 
command to do it. However, due to the poor convergence problem, I want 
to write my own code for it. When I type "ml check" , I encounter such 
error report. 

Test 1:  Calling mybiprobit2_lf to check if it computes log pseudolikelihood
         and
         does not alter coefficient vector...
         FAILED; mybiprobit2_lf returned error 198.

Here is a trace of its execution:
------------------------------------------------------------------------------
-> mybiprobit2_lf __00000C __00000D __00000E __00000F
        - `begin'
        = capture noisily version 11.2: mybiprobit2_lf __00000C __00000D __00000
> E __00000F
          --------------------------------------------- begin mybiprobit2_lf ---
          - version 9.1
          - args lnf xb zc rho
          - quietly replace `lnf' = ln(binormal( `xb',`zc', `rho')) if $ML_y1 ==
>  1
          = quietly replace __00000C = ln(binormal( __00000D,__00000E, __00000F)
> ) if treated == 1
          - quietly replace `lnf' = ln(binormal(-(`xb',`zc', `rho'))) if $ML_y1 
> == 0
          = quietly replace __00000C = ln(binormal(-(__00000D,__00000E, __00000F
> ))) if treated == 0
__00000D,__00000E,__00000F invalid name
          ----------------------------------------------- end mybiprobit2_lf ---
        - `end'
        = set trace off
------------------------------------------------------------------------------
Fix mybiprobit2_lf.
r(198);

Here, xb is for the first equation and zc is for the second equation. 
For my understanding, my likelihood evaluator for bivariate probit model
 should be right. However, when the program pick up the value of the 
variable form the data, there is some problem. That is why I have the 
_000002 invalid name. But, I am not so sure what the __000002 stands for
 and how I can correct the problem. Anyone knows what happens here?
Thank you in advance!!
. 
Jian


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