Good day stata-listers,
Thanks immensly Professor Maarten for you reply, you always give me
sound advice, I'want just to be more clear about what is going on with
me. I'm tying to estimate  4 parametres a1, a2, beta , and sigma², I'm
expecting that beta values should be postive and significantly
différent from 0, sometimes it's postive  but  "Not statistically
significantly different from zero , on other cases it's negative and
Not statistically significantly different from zero.
Thanks again Professor
Ama
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