Last week, we had an “mid-term” exam, for our introduction to statistical learning course. The question is simple: consider three points, , here Consider here some linear models, estimated using least square techniques, what would be the leave-one-out cross-validation MSE ? I like this exercise since we can compute everything easily, by hand. Since at each step we remove one single observation, only two observations remain in the sample. In with two points, fiting a linear model is straightforward (whatever the technique considered). Here, … <a href=“https://freakonometrics. …