Hey Maarten,
Some didactic and powerfull lines you wrote there!
Thank you for your suggestion of using the nbreg model as an option for the imputation model.
Also thanks a lot for pointing out the -stripplot- package by Nick Cox. A welcome tool to get diagnostics of the imputation process in an easy way.
The nbreg model proved a much better model than the standard OLS.
Although - as you already pointed out - it does not fix the problem at the upper bound, the main problem appeared to - as you suggested - at the lower bound and this was fixed by your solution.
*------------------ begin example ----------------------------
sysuse nlsw88, clear
// create some missing values
replace wage = . if runiform() < invlogit(-2 - union + south)
gen misswage = missing(wage)
ice wage union south grade, m(5) clear cmd(wage:nbreg)
stripplot wage if _mj > 0 , over(_mj) by(misswage) stack
*------------------- end example -----------------------------
Kind regards,
Adriaan Hoogendoorn
GGZ inGeest
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