simulate an error

[gabriel carvallo]

Hello,
I'm trying to do a simulation of 3 types of errors in stata. I have to create one that is E(e1|x)=0, another that is E(e2|x)=constant and E(e3|x)=0 with corrX,e3=0.2

Till now I have this in the do file:
set seed 10000
set obs 10000

g x = invnormal(uniform())
sum x

g e1 = invnormal(uniform())
sum e1

g e2 = invnormal(uniform()) + 1
sum e2

g e3 = invnormal(uniform())?????

corr x e1
corr x e2
corr x e3

I don't know how to do the third error,

Thanks

[Carlo Lazzaro]

Gabriel:
welcome to this forum.
Do you mean something along the following lines?

. set obs 1000
number of observations (_N) was 0, now 1,000

. matrix C = (1.0000, 0.2 \ 0.2, 1.0000)

. drawnorm x e , corr(C)

. correlate x e
(obs=1,000)

             |        x        e
-------------+------------------
           x |   1.0000
           e |   0.1789   1.0000

.