If residuals refer to deviations of observed values from predicted values (regression/best fit line), what are deviations of observed values from mean?
A second question: Is there a practical difference in the terms: “residuals” and “errors”? I feel like most researchers use these terms interchangeably.
When looking up the difference between “residuals” and “errors”, an person online posted this:
Error is the difference between the observed value in a sample and the true value in the population (which is actually not known). Residual is the difference between the observed value and the predicted value from the regression equation.