More Complex Feature Crosses

Now let's play with some advanced feature cross combinations. The data set in this Playground exercise looks a bit like a noisy bullseye from a game of darts, with the blue dots in the middle and the orange dots in an outer ring.

Task 1: Run this linear model as given. Spend a minute or two (but no longer) trying different learning rate settings to see if you can find any improvements. Can a linear model produce effective results for this data set?

Task 2: Now try adding in cross-product features, such as x1x2, trying to optimize performance.

  • Which features help most?
  • What is the best performance that you can get?

Task 3: When you have a good model, examine the model output surface (shown by the background color).

  1. Does it look like a linear model?
  2. How would you describe the model?

(Answers appear just below the exercise.)