[R] Why the factor levels returned by cut() are not ordered?
P.Dalgaard at biostat.ku.dk
Wed Nov 29 12:08:21 CET 2006
Wolfram Fischer wrote:
> What is the reason, that the levels of the factor
> returned by cut() are not marked as ordered levels?
>> is.ordered( cut( breaks=3, sample(10 ) ) )
It would arguably be the Right Thing, but there would be complications
in modeling, where ordered factors result in polynomial contrast coding.
(This, in my opinion, is a design mistake inherited from S, but it's not
easy to change at this stage.)
> If 'ordered' is 'TRUE', the factor levels are assumed to be ordered.
> R-help at stat.math.ethz.ch mailing list
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
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