Comments on: LOESS Utility for Excel

By: Jon Peltier

Jon Peltier — Fri, 23 Mar 2012 12:01:04 +0000

Shirley - I assume you're talking about the download from LOESS Utility – Awesome Update, since the download link on this page has been disabled. If you're getting gibberish, it means your browser is trying to render a page using the Excel add-in. This isn't going to work. Right click on the link and use Save As to save the add-in to a convenient location. Then install per instructions.

By: Shirley

Shirley — Fri, 23 Mar 2012 10:34:10 +0000

Hello,
I’m having a trouble using the link to your most current download. When I do click, a new tab opens and the browser is full of symbols (gibberish). Will you mind sending me another link to use? By the way, should this add-in also work in Excel 2010?
Thank you so much for your work on this!

Shirley

By: Norman

Norman — Wed, 08 Feb 2012 11:34:41 +0000

Thanks Jon, now it’s working.

By: DaleW

DaleW — Wed, 08 Feb 2012 02:14:27 +0000

Jon,

LOESS extrapolation seems pretty dicey to me. Results can vary widely depending on personal preference for the smoothing parameter.

Extrapolating a linear or exponential or power law or similar fit at least puts the weight of the entire dataset behind the extrapolation. One might even think of a theoretical reason to believe the extrapolation as one is finishing the graph. LOESS just puts the edge of the dataset behind the extrapolation, after effectively admitting one didn’t have a clue in advance as to the real shape of the interpolative fit one is resorting to LOESS to do.

Subject to even more concerns than most extrapolations, I’d say.

By: Jon Peltier

Jon Peltier — Tue, 07 Feb 2012 16:05:18 +0000

Norm - Sure, you can extrapolate, subject to concerns raised by any extrapolation. In the other comment I showed how to get the extrapolated values. Using the first button in the second row, you pick two ranges, each two columns wide. The first has the input data, that is, the actual X and Y values to be used in the extrapolation. The second has the output X, that is, the X values at which you want to extrapolate Y, and blank cells for the output Y. The result:

By: Norman

Norman — Mon, 06 Feb 2012 18:56:15 +0000

Hello Jon,

I have another question about the utility. According to my last two comments which
contain the necessary data I would like to know if a prediction is possible for the next two years. I found a similar comment from K. A. (Saturday, October 8, 2011, 3:39 am).
Unfortunately I did not understand your solution quite well. Maybe you could explain it to me once more (with the final table). Thank you in advance.