I have just received a soft follow-up from our dear Mr. Clough, and I have bought some time. How are things proceeding? Despite his kind words, Mr. Sheen doesn't look too friendly while asking for an update.

We are doing good, Mr. Sheen. We have already fitted some models and discovered some good hints. Nevertheless, I would like to have some sound results before sharing what we have found. Andy definitely looks comfortable in these kinds of situations, and this lets you gain some more time before actually having to show the results of your analyses. To be fair, at the moment you would not have that much to share with Mr. Sheen, and this is probably why Andy was so determined to buy some time.

As we told you before closing the previous chapter, you are now going to learn how to evaluate the performance of your models. This is, together with model estimation and validation, one of the most relevant technical skills in the field of data analysis: model performance evaluation.

But, I don't want to buy time (I would be the third person doing that in a short space of time), so let us let Andy speak. As usual, we will meet again in the summary paragraph.