The bonus question depends on the question in the image. The question in the image must be solved first, and then the bonus question. Bonus Question: You run each model for three times in question 2 (since you are making a three fold CV) hence you have three different parameter set for each model. After you decided to pick a model, which model would you use to make predictions? Or how do you calculate the parameters?

Q2. (20p) Assume that I am trying to fit a two different models to a given dataset using a 3 fold cross validation. The models has the following results: a) (10p) Which model would you choose and why? Show your calculations. b) (10p) What is a n-fold cross validation? Why do we need such a technique