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Trussman Trussman is offline
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Default how do i plot a logistic curve?

Thank you for your reply. I am trying to find a way to fit a logistic curve
to the scattergraph I have, and finding each value seems a little too work
intensive, do you have any other suggestions?

"Sean Timmons" wrote:

Not sure if you just want one value, but if so, there's a formula, LOGEST
that will return statistics for the curve. In your example, it returns
1.014717061. If that's what you wanted, put your X in, say, column A and your
Y in clumn B.

=LOGEST(B1:B100,A1:A100,TRUE,FALSE)

where the first TRUE indicates the constant is calculated normally or FALSE
if equal to 1.

and second FALSE indicates return m-coeffs and the constant b or TRUE
indicates return additional regression stats.
OR, if you want a chart, highlight your Xs and Y's, select line as the chart
type. Ensure you set your values as needed, then right click on the resulting
graph line and click Add trendline. Pick your trend line type.

Otherwise, I have no idea what you need because I never took advanced stats.
:-)

"TRUSSMAN" wrote:

I am trying to plot a logistic curve and determine r2 values for 13 data points
(0,38558),(10,49371),(20,62980),(30,76212),(40,922 28),(50,106022),(60,123203),(70,132165),(80,151326 ),(90,179323),(100,203212),(110,226546),(120,24871 0),(130,281422)