Errors and residuals

Topic: Bayesian linear regression · more questions on this topic
Normal before Student ›

Starting from {\boldsymbol{y}}={\color{blue}\boldsymbol{X}}{\boldsymbol{\beta}}+{\boldsymbol{\varepsilon}}, define the true error vector and the fitted residual vector. Which is observable after fitting the model? Show that the residuals are generally correlated even though the model errors are iid.

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