[R] how to concatenate factor vectors?

[R. Michael Weylandt]

On Thu, Oct 18, 2012 at 4:20 PM, Sam Steingold <sds at gnu.org> wrote:
>> * R. Michael Weylandt <zvpunry.jrlynaqg at tznvy.pbz> [2012-10-18 16:01:37 +0100]:
>>
>> On Thursday, October 18, 2012, Sam Steingold wrote:
>>
>>> > * Bert Gunter <thagre.oregba at trar.pbz> [2012-10-17 23:21:44 -0700]:
>>> >
>>> > However, Is level "5" in 'a' the same as level "5" in 'b' ?
>>>
>>> yes, of course.
>>> would anyone want to _different_ factors with identical string
>>> representations?!
>>
>> Off the cuff, studying education and grades: F could be a grade or a
>> gender.
>
> would you ever want to concatenate a vector of grades with a vector of
> genders?

You said nothing about having good reasons to do manipulation s
thereupon. As I read the question (changing "to" to "two"), you were
just asking if two distinct factors might share string representations
;-)

Perhaps even better: grades on two different exams: sharing the same
level set entirely, but from a statistical point of view, distinct
(but likely confounded)

Cheers,
M