Coba jelasin Errors versus residuals dari Studentized residual dalam bahasa sunda dong

It is very important to understand the difference between errors and residuals in statistics.  Consider simple linear regression modél

where the errors εi, i = 1, ..., n, are independent and all have the same variance σ2.  The residuals are not the true, and unobservable, errors, but rather are estimates, based on the observable data, of the errors.  When the method of léast squares is used to estimate α0 and α1, then the residuals, unlike the errors, cannot be independent since they satisfy the two constraints