FORECAST function isnt producing wanted results
 

i have a graph of three points, and i use FORECAST to find a 4th point
within those three points, but the point that FORECAST comes up with
doesnt fall on the graph. why not and is there anything i can do?


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lsu-i-like
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Your graph is probably not linear, whereas the result given by the
forecast function is linear.

Mangesh


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mangesh_yadav
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Infact in the graph, you can right-click and add a trend line. Also
select each of the options i.e. linear, or exponential, and check the
box for show equation. Use the one which is the best fit, and use the
quation.

Mangesh


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why is a polynomial trend line different from the original graph that
excel produces?


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Excel apparently uses Bezier curves to smooth its graphs. I *guess* it sets
up a lot of interpolation points for the purpose of charting any of its
trendlines.

If you are at all comfortable with using VBA, you might want to download my
cubic spline code (posted under Braden; watch out for the unintended line
breaks. See
http://groups-beta.google.com/group/...c412511748ebc9

An advanced search under the topic "cubic spline", author "Braden", group
"microsoft.public.excel.*" will yield more info.

HTH
Dave Braden

"lsu-i-like" wrote
in message ...

why is a polynomial trend line different from the original graph that
excel produces?


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