fracpoly: fracpoly

In jrs95/mvshape: mvshape

fracpoly

Description

fracpoly fits the best fitting fractional polynomial of degree 1 and 2.

Usage

fracpoly(y = y, x = x, covar = NULL, family = "gaussian")

Arguments

y	outcome.
x	exposure.
covar	data.frame with covariates.
family	the glm family (options: gaussian and binomial).

Value

List of best-fitting polynomials of degrees 1 and 2 as well as associated statistics.

power_d1	power of the best-fitting fractional polynomial of degree 1
fp1	model of the best-fitting fractional polynomial of degree 1
power_d2	powers of the best-fitting fractional polynomial of degree 2
fp2	model of the best-fitting fractional polynomial of degree 2
p_d1	p-value testing the best-fitting fractional polynomial of degree 1 against the linear model
p_d2	p-value testing the best-fitting fractional polynomial of degree 2 against the best-fitting fractional polynomial of degree 2
xmin	miniumum value of the exposure
xmax	maximum value of the exposure
family	family used in the analysis

Author(s)

James Staley [e-mail]

Examples

# Data
y <- rnorm(5000)
x <- rnorm(5000, 10, 1)
c1 <- rbinom(5000, 1, 0.5)
c2 <- rnorm(5000)
study <- c(rep("study1", 1000), rep("study2", 1000), rep("study3", 1000), rep("study4", 1000), rep("study5", 1000))
covar <- data.frame(c1 = c1, c2 = c2, study = study)

# Analyses
res <- fracpoly(y = y, x = x, covar = covar, family = "gaussian")

jrs95/mvshape documentation built on April 8, 2024, 6:39 a.m.