Steven wrote:
<In my first time period for my firms, I have no exits so the hazard
coefficient is very low. Unfortunately, because there are no exits it also
indicates it is non-significant. (p=.969).>
At first glance, this result would seem consistent with your data generating
process: no exits mean very low hazard and very high p-value. Probably, the
best solution here is try to explain (eg. according to the economic theory
or taking a look at previous researches in the same field) why this result
is or is not reasonable.
<Given there are no standard errors if there is not an exit..>
This statement seems a little bewildering, as you actually reported a
standard error for TP1 (528.1418).
HTH and Kind Regards,
Carlo
-----Messaggio originale-----
Da: [email protected]
[mailto:[email protected]] Per conto di Bradley, Steve
Inviato: giovedì 30 luglio 2009 23.54
A: '[email protected]'
Oggetto: st: stpiece - general hazard estimation question
Statlisters,
I have a question regarding the estimation of hazards when there isn't one
for a particular time period. In my first time period for my firms, I have
no exits so the hazard coefficient is very low. Unfortunately, because
there are no exits it also indicates it is non-significant. (p=.969).
_t Coef. Std. Err. z P>z
TP1 -20.66249 528.1418 -0.04 0.969
TP2 -5.362681 .8858187 -6.05 0.000
TP3 -5.62141 .7207315 -7.80 0.000
As an experiment, if I add one firm exit during time period 1 to confirm
this is an estimation problem I get:
_t | Coef. Std. Err. z P>|z| [95% Conf.
Interval]
-------------+--------------------------------------------------------------
--
TP1 | -7.638006 1.206193 -6.33 0.000 -10.0021
-5.273911
TP2 | -4.855396 .782516 -6.20 0.000 -6.3891 -3.321693
TP3 | -5.48794 .711463 -7.71 0.000 -6.882382
-4.093498
I am wondering if there is an appropriate solution to this problem. Given
there are no standard errors if there is not an exit, can I consider the
standard error 0 and use the original coefficient or is it unreliable as
well?
Thanks!
Steven W. Bradley, Ph.D.
Department of Management & Entrepreneurship
One Bear Place #98006
Baylor University
Waco, TX 76798
(office) 254.710.3921
[email protected]
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