- Choose which features to include
- Choose the right value for lambda
- These are what discussed in "mode selection"

- Overfitting really not a good example for predicting the future examples

- Suppose we choosing which parameters and which degree of polynomials
- Here's what it works
- it could determine how well and generalized the value of d
- test each d by using jtest(theta) , inject the parameters into the Jtest
- choosing whichever has the lowest error value
- Still not a good point for generaliz e the parameters
- Perhaps is the best, but not always the generalize. May tends to be overfitting.