| |
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]
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
***********************
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/