Variance of a Curve

Hi,

Could you please tell me how to find the variance of a plot rather than that
of data. In other words, I have the Y-data and wold like to know how much it
is spread about its peak at X

For example if the Data is as follows

Y = 0.2, 0.5, 1.2, ..., 4.6, 5.4, 5.1, ..., 1.9, 0.8, 0.5
X = 1, 2, 3 ... 20

with the peak (5.4) at 11

I would like to find out how much the variance of the curve is about this
peak at 11.

Thanks a ton for the help.
Soumyadip.



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