A word by way of decoding:
Level of documentation in Stata is an ordered categorical
variable, with some idiosyncratic terminology.
1. "Documented" usually means that there is extensive
explanation in the manuals, and corresponding, usually
briefer, material in the on-line help. There may well
be other material in FAQs, the Stata Journal, etc.
2. "Undocumented" usually means that something is not
documented in the (latest version of the) manuals.
The key to unlock the
door here (which was not in fact locked in the first
place) is -help undocumented- which, oxymoronically
or otherwise, reveals various commands not explained
in the manuals. Again, there may well
be other material in FAQs, the Stata Journal, etc.
3. "Not documented" often means what you might think
it means, but even this category is not homogeneous
and ranges from some commands known to users to
commands known only to StataCorp developers. I can't
give you any examples of the latter, by definition,
but I assume that they exist. I could give you examples
of the former, but I have to go and teach right now....
Nick
n.j.cox@durham.ac.uk
David Elliott
Also, thank you for tipping me to the undocumented _natscale - it will
prove to be useful.
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