Dear Statalisters,
I'm trying to estimate power of a non-linear regression by simulation.
There are three parameters of interest and I can generate samples under H0
(no trend) and H1 (particular model of interest).
The problem is how to write the parameter estimates under H0 and H1 to a
file. In the code below, the estimation is performed twice - under H0 and
H1. What I would like to do is post the 6 estimates in one go to the output
file, rather than output to two separate files which would be merged.
forvalues i=1/5000 {
/* evaluate when H0 true */
replace err = 0 + 3.5*invnorm(uniform())
replace tempy = 0 +err
nl hyp tempy dose, iterate(30) eps(0.0001)
/* How do I save parameter estimates from H0 ? */
/* evaluate when H1 true */
replace tempy = yh +err
nl hyp tempy dose, iterate(30) eps(0.0001)
/* here I save the results from estimate given H1 */
post `powerdat' (_b[B0]) (_b[B1]) (e(r2_a))
Any thoughts anybody? Ideally the last statement would be like:
post `powerdat' (_b[B0]) (_b[B1]) (e(r2_a)) (_b[B0]) (_b[B1])
(e(r2_a))
Where the first 3 are from the estimate under H0 and the second 3 are from
H1
Paul Silcocks BM MSc FRCPath FFPHM CStat
Assistant Director (Research & Intelligence)
Trent Cancer Registry
tel (+44) 114 2265351 / 2265665 (direct line)
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