[Rd] A "safe" do.call

Prof Brian Ripley ripley at stats.ox.ac.uk
Wed Jan 30 15:27:55 CET 2008


This is a 'White Book' function, not really ours to re-design.
(Although the glm help page in the White Book's description of '...' never 
was correct of any S-PLUS that I used, and doesn't make a great deal of 
sense.)

I never really saw the point of glm.control(), but it might have allowed 
for future expansion that never happened.

On Wed, 30 Jan 2008, hadley wickham wrote:

>>     hw> That seems a perfectly good reason not to use ... - but
>>     hw> if you are going to use ... it seems like you shouldn't
>>     hw> warn on mismatched argument names.
>>
>> I disagree.
>>
>> One "famous" example on this was -- in S-plus, early 1990s --
>> known about S users back then, and it happened here (as well),
>> not in theory: a scientist who later came for consulting to us
>> did a logistic regression
>>
>>   mod1 <- glm(y ~ x1 + x2 + ....,  .......
>>               data = ....., famliy = binomial)
>>   summary(mod1)
>>   ...
>>
>> and was wondering about the logistic regression coefficients and
>> their interpretation and more things
>> until we found out the small typo above
>> which made glm() compute a ("gaussian") model even though the
>> user had clearly said he wanted a logistic one.
>>
>> Can you see the point?
>
> The point is that glm shouldn't use ... but should explicitly list all
> of the arguments that it takes?  Why does glm need to use ... in your
> example?
>
> If you know the set of possible arguments in advance, why not list
> them explicitly and document them individually, and not use ... at
> all?
>
> Hadley
>
> --
> http://had.co.nz/
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595



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