st: IVTOBIT, missing values, panel

["joe jacob" <otharain@hotmail.com>]

Dear listers,

I have three questions. First is  a follow up to a question that was posted 
last year  (31 Jul 2002, to be precise) by Kee-Lee Lee. The problem is one 
of getting the error message ---matrix has missing values--while running 
IVTOBIT. There is no missing value in the variables used, though.

I followed the suggestion of Nick Cox to  --set trace on--. I attach the 
stata output below. Could anyone figure out the reason?

My  second question is, is anyone aware of any stata module that extends 
ivtobit to a panel setting?

Finally, I would like to know if it is possible to estimate the Log 
Likelihood after estimating ivtobit.

Many thanks in advance,


Joe Jacob

****Stata Output******

ivtobit ird, endog(expsal) iv(wager ltlnou size2) exog(outs forg

>  y90 y91 y92 y93 y94 y95 y96 y97) ll(0) ul(1900000000)
- version 6.0
- syntax varlist [if] [in], ENDOG(varlist) IV(varlist) EXOG(varlist) 
[LL(real 0

> ) UL(real 9999999)]
- local depvar "`varlist'"
- tempvar tmpy touse
- marksample touse
- local niv : word count `iv'
- local nendog : word count `endog'
- local nexog : word count `exog'
- local K=`nexog'+`niv'
- matrix Dhat=J(`K'+1,`nendog'+`nexog'+1,0)
- matrix Dhat[`niv'+1,`nendog'+1]=I(`nexog'+1)
- parse "`endog'", parse(" ")
- local e = 1
- while `e'<=`nendog' {
- qui regress `1' `iv' `exog' if `touse'
- matrix tmp=get(_b)
- matrix Dhat[1,`e']=tmp'
- tempvar fitted`e' resid`e'
- qui predict `fitted`e'' `if'
- version 7.0
- if _caller()<=5 | "`e(predict)'"=="" {
 _predict `0'
 }
- else {
- local v=_caller()
- version `v'
- `e(predict)' `0'
- version 6
- local myopts "COVratio DFBeta(varname) DFIts E(string) Hat Leverage 
Pr(string

> ) Welsch YStar(string)"
- _pred_se "`myopts'" `0'
- version 6.0
- sret clear
- gettoken ouser 0 : 0
- local orig `"`0'"'
- gettoken varn 0 : 0, parse(" ,[")
- gettoken nxt : 0, parse(" ,[(")
- if !(`"`nxt'"'=="" | `"`nxt'"'=="if" | `"`nxt'"'=="in" | `"`nxt'"'==",") {
 local typ `varn'
 gettoken varn 0 : 0, parse(" ,[")
 }
- syntax [if] [in] [, `ouser' CONStant(varname numeric) noOFFset *]
- if `"`options'"' != "" {
 _predict `orig'
 sret local done 1
 exit
 }
- confirm new var `varn'
- sret local done 0
- sret local typ `"`typ'"'
- sret local varn `"`varn'"'
- sret local rest `"`0'"'
- if `s(done)' { exit }
- local vtyp `s(typ)'
- local varn `s(varn)'
- local 0 `"`s(rest)'"'
- syntax [if] [in] [, `myopts' noOFFset]
- local type "`covrati'`dfits'`leverag'`welsch'`hat'"
- local args `"`dfbeta'`pr'`e'`ystar'"'
- if "`type'"=="" & `"`args'"'=="" {
- di in gr "(option xb assumed; fitted values)"
- _predict `vtyp' `varn' `if' `in', `offset'
- label var `varn' "Fitted values"
- exit
- }
- qui replace `fitted`e'' =. if `1' ==.
- qui predict `resid`e'' `if', residuals
- version 7.0
- if _caller()<=5 | "`e(predict)'"=="" {
 _predict `0'
 }
- else {
- local v=_caller()
- version `v'
- `e(predict)' `0'
- version 6
- local myopts "COVratio DFBeta(varname) DFIts E(string) Hat Leverage 
Pr(string

> ) Welsch YStar(string)"
- _pred_se "`myopts'" `0'
- version 6.0
- sret clear
- gettoken ouser 0 : 0
- local orig `"`0'"'
- gettoken varn 0 : 0, parse(" ,[")
- gettoken nxt : 0, parse(" ,[(")
- if !(`"`nxt'"'=="" | `"`nxt'"'=="if" | `"`nxt'"'=="in" | `"`nxt'"'==",") {
 local typ `varn'
 gettoken varn 0 : 0, parse(" ,[")
 }
- syntax [if] [in] [, `ouser' CONStant(varname numeric) noOFFset *]
- if `"`options'"' != "" {
- _predict `orig'
- sret local done 1
- exit
- if `s(done)' { exit }
- }
- qui replace `resid`e'' =. if `1' ==.
- local fitted "`fitted' `fitted`e''"
- local resid "`resid' `resid`e''"
- mac shift
- local e = 1 + `e'
- }
- while `e'<=`nendog' {
 qui regress `1' `iv' `exog' if `touse'
 matrix tmp=get(_b)
 matrix Dhat[1,`e']=tmp'
 tempvar fitted`e' resid`e'
 qui predict `fitted`e'' `if'
 qui replace `fitted`e'' =. if `1' ==.
 qui predict `resid`e'' `if', residuals
 qui replace `resid`e'' =. if `1' ==.
 local fitted "`fitted' `fitted`e''"
 local resid "`resid' `resid`e''"
 mac shift
 local e = 1 + `e'
 }
- qui tobit `depvar' `fitted' `exog' if `touse',ll(`ll') ul(`ul')
- matrix tmp = get(_b)
- matrix beta=tmp[1,1..`nendog']
- local nobs=e(N)
- qui tobit `depvar' `iv' `exog' `resid' if `touse',ll(`ll') ul(`ul')
- local obs = e(N)
- local df = e(df_m)
- matrix tmp = get(_b)
- matrix alpha=J(1,`K'+1,0)
- matrix alpha[1,1]=tmp[1,1..`K']
- matrix alpha[1,`K'+1]=tmp[1,`K'+`nendog'+1]
matrix has missing values
r(504);

end of do-file
r(504);

.

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