Part II: beyond linearity

Question 1

What is the difference between piecewise polynomials and splines?

Answer 1

Insisting on continuity with splines so we dont break the fit.

Question 2

What is the advantage of natural cubic splines over piecewise polynomial fits?

Answer 2

• No flapping in the ends due to boundary knots
• Continuity around the knots

Question 3

What is the advantage of smoothing splines?

Answer 3

We avoid the rapid fluctuations by penalizing with lambda.

Question 4

What is a GAM

Answer 4

generalized additive model. Extends the generalized linear model so we can add non linear responses. each variable has a function which is estimates iteratively from an initial guess.