Re: [R] smoothing function for proportions

2007-08-10 Thread Rose Hoberman
Sorry, forgot to attach the graph.

On 8/10/07, Rose Hoberman <[EMAIL PROTECTED]> wrote:
> I am looking for a function that can fit a smooth function to a vector
> of estimated proportions, such that the smoothed value is within
> specified confidence bounds of each proportion.  In other words, given
> a small number of trials and large confidence intervals, I would
> prefer the function to vary smoothly, but given a large number of
> trials and small confidence intervals, I would prefer the function to
> lie within the confidence intervals, even if it is not smooth.
>
> I have attached a postscript file illustrating a data set I would like
> to smooth.  As the figure shows, for large values of x, I have few
> data points, and so the ML estimate of the proportion varies widely,
> and the confidence intervals are very large.  When I use the
> smooth.spline function with a large value of spar (the red line), the
> function is not as smooth as desired for large values of x.  When I
> use a smaller value of spar (the green line), the function fails to
> stay within the confidence bounds of the proportions.   Is there a
> smoothing function for which I can specify upper and lower limits for
> the y value for specific values of x?
>
> Thanks for any suggestions,
>
> Rose
>


smoothProportions.ps
Description: PostScript document
__
R-help@stat.math.ethz.ch 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] smoothing function for proportions

2007-08-10 Thread Rose Hoberman
I am looking for a function that can fit a smooth function to a vector
of estimated proportions, such that the smoothed value is within
specified confidence bounds of each proportion.  In other words, given
a small number of trials and large confidence intervals, I would
prefer the function to vary smoothly, but given a large number of
trials and small confidence intervals, I would prefer the function to
lie within the confidence intervals, even if it is not smooth.

I have attached a postscript file illustrating a data set I would like
to smooth.  As the figure shows, for large values of x, I have few
data points, and so the ML estimate of the proportion varies widely,
and the confidence intervals are very large.  When I use the
smooth.spline function with a large value of spar (the red line), the
function is not as smooth as desired for large values of x.  When I
use a smaller value of spar (the green line), the function fails to
stay within the confidence bounds of the proportions.   Is there a
smoothing function for which I can specify upper and lower limits for
the y value for specific values of x?

Thanks for any suggestions,

Rose

__
R-help@stat.math.ethz.ch 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.