Hi all,

After reading many many topics I have a question on the possibilities of any test to check whether the coefficients differ significantly or not.
I know about the -test- or -testparm- command but unfortunately can't find what I am looking for.
I test the effect of CEO pay scheme dependence on shareholder return (1=no, 2=yes) on the number of relative layoffs of the firm (percentage). Using paneldata, 5500 firms over 12 year:.
I want to split the effect of my main dependent for firms that made more or less profit than the year before, therefore a binairy variable (1= decreasing, 0=increasing).

xtreg RLO_per CeoPay#D_prof logsize logemployee tobinsq lev prof Domestic BoardSize i.n_ShhlType i.year i.n_Industry i.n_Country, vce(robust)

Now I want to test whether the coefficient of CeoPay=yes given decreasing profits (=0.2976) differs from the coefficient CeoPay=no given decreasing profits (=0.0683).

Anyone knows a proper method and stata command to do so?

Kinds regards,
Stan


Random-effects GLS regression Number of obs = 39,140
Group variable: ID Number of groups = 5,531

R-sq: Obs per group:
within = 0.0169 min = 1
between = 0.1029 avg = 7.1
overall = 0.0399 max = 14

Wald chi2(148) = .
corr(u_i, X) = 0 (assumed) Prob > chi2 = .

(Std. Err. adjusted for 5,531 clusters in ID)
---------------------------------------------------------------------------------------------------------------------------
| Robust
RLO_per | Coef. Std. Err. z P>|z| [95% Conf. Interval]
----------------------------------------------------------+----------------------------------------------------------------
CeoPay#D_prof |
1 1 | .0683347 .0302017 2.26 0.024 .0091404 .1275289
2 0 | .0298435 .0413767 0.72 0.471 -.0512534 .1109404
2 1 | .2976375 .0570798 5.21 0.000 .1857632 .4095118
|
logsize | .1262604 .0180784 6.98 0.000 .0908274 .1616933
logemployee | .0596924 .0114406 5.22 0.000 .0372692 .0821157
tobinsq | .0300837 .0107114 2.81 0.005 .0090897 .0510778
lev | .0175412 .1009887 0.17 0.862 -.180393 .2154755
prof | -2.063631 .2746226 -7.51 0.000 -2.601882 -1.525381
Domestic | -.023963 .0411957 -0.58 0.561 -.1047052 .0567792
BoardSize | .0036602 .0058319 0.63 0.530 -.0077701 .0150906