I am fitting data to a parabolic equation using the least squares fit method. Each data point that goes into the fit is the average of 5 data points at that x value, so that each point has error bars that come from the standard deviation of those 5 y values.(adsbygoogle = window.adsbygoogle || []).push({});

I have a fitted equation, and I can calculate the residuals, but how can I calculate the uncertainty for a single point on the fitted line? So say the fitted equation is y = ax^2 +bx+c. I want to be able to plug in a value for x, get a value for y (that much is trivial) and get the associated uncertainty on that y value.

Thanks

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# Uncertainty for least squares fit

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