Least Squares as a square (geogebra illustration)
This is a simple illustration of the principle of least squares. The learner has to fit a line to three data points by adjusting the slope and intercept of the line.
The main point of the illustration is that we visualise the SQUARE of the residuals, and the total sum of squares is made available to the learner to guide the fit.
A simple tickbox allows the least squares calculated line of best fit to be superimposed.