Thanks for your response, Dieter.
I realize these limitations. However, I know that my actual dataset is
reasonably well behaved in the range I want to predict, and I'm not using
the predicted values for any further analysis, only for schematic purposes
in the plot.
I'm still curious if this type of extension of a loess line is possible,
notwithstanding its statistical shortcomings.
Cheers,
Alex.
>loess is "local polynomial regression fitting". It is good to guide your
eyes
>through confusing data points, but not at all suitable for extrapolation
(that's
>why it is good locally). I would say, it is not even good for
interpolation, but
>that a matter of discussion.
>I doubt that an extrapolation of a factor 2 beyond the initial range is
possible
>at all without a VERY good model of your data. But in each case, you need a
>model, for example from earlier longer records. How does the poor function
know
>that your data do not bend down logistic-like after you last value?
>
>
>Dieter
Alex Karner <aakarner <at> ucdavis.edu> writes:
> I'm trying to (1) plot loess lines for each of my groupings using the
same
> color for each group; (2) plot loess predicted values.
>
> The first part is easy:
.. Example removed... Thanks, it was a good example of what you wanted!
> My question is, how do I plot predicted values from loess to extend the
> lines beyond the range of x? Let's say I want all lines to stop at x = 15.
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