Regression splines (parametric Smoothing splines (nonparametric Additional notes o These types of fixed-knot models are referred to as regression splines o Recall that cubic splines contain 4+K degrees of freedom: K+1 regions x 4 parameters per region-K knots x 3 constraints per knot It is claimed that cubic splines are the lowest order spline for which the discontinuity at the knots cannot be noticed by the human eye o There is rarely any need to go beyond cubic splines,which are by far the most common type of splines in practice Patrick Breheny STA 621:Nonparametric StatisticsIntroduction Regression splines (parametric) Smoothing splines (nonparametric) Additional notes These types of fixed-knot models are referred to as regression splines Recall that cubic splines contain 4 + K degrees of freedom: K + 1 regions × 4 parameters per region - K knots × 3 constraints per knot It is claimed that cubic splines are the lowest order spline for which the discontinuity at the knots cannot be noticed by the human eye There is rarely any need to go beyond cubic splines, which are by far the most common type of splines in practice Patrick Breheny STA 621: Nonparametric Statistics