Topic: Piecewise Regression and Splines

Why Natural Splines Become Linear at the Boundaries

Uncertainty for Fixed-Knot Segmented Fits

The Truncated Power Basis for Cubic Splines

The Curvature Penalty in Smoothing Splines

Testing Added Segments at Prespecified Knots

Selecting Smoothing Strength for a Smoothing Spline

Regression Splines Versus Smoothing Splines

Reading Segment Slopes and Fitted Values

Pitfalls in Searching for Breakpoints

Modeling Jumps and Slope Changes at Breakpoints