This is a read-only property which is maintained for you by RainPro to allow you to use the ‘modelfit’ style and then plot the residuals for each datapoint as an extra chart. You may like to overlay a frequency histogram to check that the residuals are normally distributed.

coeff„ch.Query 'Residuals'

The result will be a numeric vector with one value for each value in the fitted data. Where missing values were marked in the input data, there will be corresponding missing values in the computed result, so that the original and fitted series always match exactly in length.

See also ...
OrderOfFit – polynomial degree of modelfit