

hm567 wrote:
> 
> I am unsure about spar being the smoothness parameter, about where to put
> the standard errors of the points, and about the return of the
> smooth.spline function:

> Smoothing Parameter  spar= 0.5  lambda= 0.006833112 

> 
> best regards,

> 
Basically, the implementation based on the attached paper, for a standard
error of points =1.0,
the smoothing is too insensitive to the lambda smoothness parameter.
>From 1 to almost 0.01, there is almost no smoothing... Only from 0.01 to 0
does one start to see smoothing in action with the limit at 0 being a
straight line.
Note that this implementation's parameter is (1 - parameter)

With R smooth.spline, 'spar' reflects well the smoothness in that:
. at 0%, the spline interpolates
. at 40% already, its shape is very different from the 0% one  ( for my
implementation, they are still same )
. at 90% it is almost a straight line
. at 100% it is definitely a straight line

This is the behavior that I wish to have.
It seems I need to change my lambda with some transformation that is similar
to the one in the doc of smooth.spline   (spar to lambda). Perhaps the
reverse one. But I can't see how to do it.

The other question is the standard errors. What do they correspond to in the
doc of smooth.spline?

Regards,
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