In tbk03/cjmr:

knitr::opts_chunk$set(echo = TRUE)

Questions

Is at least one of the predictors useful in predicting the response? F-statistic.
Do all the predictors help to explain Y, or is it a subset of predictors that help to explain Y? Compare models with different subsets. Metric include AIC, BIC, adjusted R^2^ and Mallow's Cp.
How well does the model fit the data? RSE and R^2^ (training data)
Given a set of predictor values, what response value should we predict? And, how accurate is our prediction? RSE and R^2^ (test data)