How to estimate the accuracy for an estimated tine segment when actual line is known?

Suppose I have a set of XY coordinates (pink dots including noise)which is a measured values of a line segment (Black line). After estimating the best line (Orange line) for the measured data points, how can I calculate the accuracy of the fitted line with the actual one.

[Walter Roberson]

How are you doing the estimation? In particular are you using polyfit()

[Tharindu Weerakoon]

Estimating using Orthogonal Least squares method which is a separately written matlab m-file, not the ployfit() function.

Answer 1

[Image Analyst]

You can get the residuals and use R or R^2 or the sum of absolute differences. R squared is a pretty common metric - why not use that?