--- Ren� Wevers <[email protected]> wrote:
> I also want to impute a discrete variable, namely the age of
> companies in years (integers) with a maximum of 37 years (age has
> only been measured as of 1967). The distribution is for this variable
> is definately not normal, but it is not extremely skewed as well.
> Can I manipulate my data such that I can apply standard (OLS)
> regression to impute with -ice- or should I apply ordinal logistic
> regression in this case?
You could have a look at -gladder- which compares various
transformations against a normal curve. For normality checking I prefer
-hangroot-, downloadable from -scc-, over a histogram with a normal
density plotted through it. (though I am not completely neutral as I am
the author of -hangroot-.) I have also heard request for StataCorp to
increase the number of categories allowed in -ologit- for just the kind
of imputation analysis you are proposing, so there are other persons
who think that it is reasonable to use -ologit- this way. I would say
try to transform age into something more nearly Gaussian and use
-regress- and use -ologit- and see if it makes a difference.
Hope this helps,
Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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