I am really sorry but I am quite confused.
I have panel data (200 firms over the time period of 2002 - 2014). I ran a test whether I should use fe or re; and I think I got the result of random effects, which makes sense since my sample is drawn from different industries. The result made me think I need to use random effects.
code:
. hausman fe re
---- Coefficients ----
(b) (B) (b-B) sqrt(diag(V_b-V_B))
fe re Difference S.E.
zchangeinROA -.0078418 -.0094914 .0016495 .0002656
Narcissimi~ .004696 -.0003595 .0050556 .0030671
interaction -.0008962 -.0005818 -.0003144 .0003695
zlntotal_a~ .0674206 .0044034 .0630172 .0163112
zlnrevenue -.0052717 -.001084 -.0041878 .0122064
zrole -.0097101 -.0096499 -.0000602 .001937
b = consistent under Ho and Ha; obtained from xtreg
B = inconsistent under Ha, efficient under Ho; obtained from xtreg
Test: Ho: difference in coefficients not systematic
chi2(6) = (b-B)'[(V_b-V_B)^(-1)](b-B)
= 3.92
Prob>chi2 = 0.6881
(V_b-V_B is not positive definite)
Now I did a Breusch and Pagan test to see if I could use pooled OLS instead of random effects. As I understood it, I reject the Null and thus need to do a random effects. Could you help me if I did the right decisions? This is for my thesis, so any help or explanatio is appreciated.
Breusch and Pagan Lagrangian multiplier test for random effects
workforcechange[firm_ID,t] = Xb + u[firm_ID] + e[firm_ID,t]
Estimated results:
| Var sd = sqrt(Var)
---------+-----------------------------
workfor~e | .0253792 .1593084
e | .0232228 .1523903
u | .0019666 .0443464
Test: Var(u) = 0
chibar2(01) = 88.06
Prob > chibar2 = 0.0000
I posted the same question here; but have not gotten a reply yet.
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