mfp (version 1.4.6)

fp: Fractional Polynomial Transformation

Description

This function defines a fractional polynomial object for a quantitative input variable x.

Usage

fp(x, df = 4, select = NA, alpha = NA, scale=TRUE)

Arguments

x

quantitative input variable.

df

degrees of freedom of the FP model. df=4: FP model with maximum permitted degree m=2 (default), df=2: FP model with maximum permitted degree m=1, df=1: Linear FP model.

select

sets the variable selection level for the input variable.

alpha

sets the FP selection level for the input variable.

scale

use pre-transformation scaling to avoid numerical problems (default=TRUE).

Value

Examples

fp(x, df = 4, select = 0.05, scale = FALSE)