Piecewise Polynomials and Splines
Fitted Natural Spline Model
• Each term 4 df (except famhist)
• Pointwise standard error curves
• Rugplot shows location of x values
Tensor Product Basis
DF = 1 +(4-1) + (4-1) = 7
DF = 4 x 4 = 16
Thin-Plate Spline
DF = 15
Red points are knots
Top Related