[R] Splines under tension

[David Winsemius]

On May 12, 2010, at 2:41 PM, David Winsemius wrote:

>
> On May 12, 2010, at 2:37 PM, Greg Snow wrote:
>
>> I think this last line is a fortune candidate:
>>
>> It's not just that different disciplines rediscover the same ideas,  
>> they also relabel them.
>>
>
> With apologies to Aretha: I second that emotion.

Further Apologies:
An r-helper with a better memory than mine points out that I should  
have cited Smokey rather than Aretha.

-- 

David.
>
> -- 
> David.
>
>>
>> -- 
>> Gregory (Greg) L. Snow Ph.D.
>> Statistical Data Center
>> Intermountain Healthcare
>> greg.snow at imail.org
>> 801.408.8111
>>
>>
>>> -----Original Message-----
>>> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
>>> project.org] On Behalf Of Terry Therneau
>>> Sent: Wednesday, May 12, 2010 6:49 AM
>>> To: sam.e
>>> Cc: r-help at r-project.org
>>> Subject: Re: [R] Splines under tension
>>>
>>> ---begin included message ---
>>>
>>> Does anyone know if R has a function for splines under tension. I  
>>> know
>>> there are numerous packages for spline interpolation within R i just
>>> can't find one that lets you determine the tension factor.
>>>
>>> ------------------
>>>
>>> In the statistics literature these are called "smoothing  
>>> splines".  For
>>> instance the s(x) construct in gam or pspline(x) in a coxph formula.
>>> There are multiple ways to specify the 'tension factor', many in the
>>> statistics community prefer the 'equivalent degrees of freedom' so  
>>> you
>>> will often see df=___ in the examples.  You can also directly  
>>> enter a
>>> penalty mulitplier.
>>>  To get a clearer answer you would need to give the explicit
>>> definition of "tension factor" from the literature you are quoting.
>>> It's not just that different disciplines rediscover the same ideas,
>>> they
>>> also relabel them.
>>>
>>> Terry Therneau
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide http://www.R-project.org/posting-
>>> guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
> David Winsemius, MD
> West Hartford, CT
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

David Winsemius, MD
West Hartford, CT