Dear Listers
The following is a random effect panel regression output. I don't
know why sigma_u==0. because of this, i cannot run xthausman. can you help
me out?
thanks
. xtreg invest l_tobinq cash nta, re
Random-effects GLS regression Number of obs =
1680
Group variable (i) : stkcd Number of groups
= 280
R-sq: within = 0.0862 Obs per group: min
= 6
between = 0.5242 avg = 6.0
overall = 0.1601 max = 6
Random effects u_i ~ Gaussian Wald chi2(3) =
319.48
corr(u_i, X) = 0 (assumed) Prob > chi2 =
0.0000
----------------------------------------------------------------------------
--
invest | Coef. Std. Err. z P>|z| [95% Conf.
Interval]
-------------+--------------------------------------------------------------
--
l_tobinq | .1258068 .0586902 2.14 0.032 .0107761 .2408374
cash | .1442353 .008403 17.16 0.000 .1277656 .160705
nta | -.1554083 .0710843 -2.19
0.029 -.294731 -.0160855
_cons | 3.458639 1.513534 2.29 0.022 .4921665 6.425112
-------------+--------------------------------------------------------------
--
sigma_u | 0
sigma_e | 2.6171947
rho | 0 (fraction of variance due to u_i)
----------------------------------------------------------------------------
--
*
* 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/
