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st: over identification  test after reg3
I am trying to run an over identification test for a constrained 
simultaneaous model (with reg3). It is the  following :
/*symmetry*/
constraint 1 [dw1]dlnp2 = [dw2]dlnp1
constraint 2 [dw1]dlnp3 = [dw3]dlnp1
constraint 3 [dw2]dlnp3 = [dw3]dlnp2
/*homogeneity*/
constraint 4 [dw1]dlnp1 + [dw1]dlnp2 + [dw1]dlnp3 + [dw1]dlnp4 =0 
constraint 5 [dw2]dlnp1 + [dw2]dlnp2 + [dw2]dlnp3 + [dw2]dlnp4 =0 
constraint 6 [dw3]dlnp1 + [dw3]dlnp2 + [dw3]dlnp3 + [dw3]dlnp4 =0
reg3(dw1  ddeflexp dlnp1 dlnp2 dlnp3 dlnp4  period  dlnyear) /*
*/  (dw2  ddeflexp dlnp1 dlnp2  dlnp3 dlnp4   period  dlnyear)/*
*/  (dw3  ddeflexp dlnp1 dlnp2 dlnp3 dlnp4  period  dlnyear) /*
*/  (exp  explag PIB period)/*
*/  (p1   pxlaitcomteinterp  pxlaitcomteinterplag1     ind_sal_interp 
pourc_vol_ean_1 pourc_vol_MDDHD_1)/* */  (p2    pxlaitstandinterp  
pxlaitstandinterplag1  ind_sal_interp  pourc_vol_ean_2 pourc_vol_MDDHD_2)/*
*/  (p3   pxlaitcomteinterp  pxlaitcomteinterplag1   pxlaitstandinterp  
pxlaitstandinterplag1  ind_sal_interp  pourc_vol_ean_3 pourc_vol_MDDHD_3 
pourc_vol_parm pourc_vol_beauf) /*
*/  (p4   pxlaitstandinterp  pxlaitstandinterplag1  ind_sal_interp  
pourc_vol_ean_4 pourc_vol_MDDHD_4),    cons(1-6)
The last 5 equations correspond to my instrumentations.
As it isn't possible to use the overid command (because I used reg3 and 
not ivreg2), I have to rebuild the sargan test of overidentification.
I have found a the little and useful program written by Christopher Baum 
to rebuild the  J stat. I just don't well understand the degrees of 
freedom calculated in his program (df = #eqns * #exog - #betas estimated 
(net) =  rowsof(esigma) * colsof(w) - (colsof(beta) - `nconstraint')).
With this, I obtain a df of 150 which is enormous. I'm probably  wrong 
somewhere. If someone has any suggestions....
Thank you very much.
val�rie.
--
***********************
Val�rie Orozco
INRA ESR Toulouse
ESR INRA - BP52627 - 31326 Castanet Tolosan Cedex 
[email protected]
05-61-28-50-97
***********************
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